TITLE: Herbicide Tolerance/Resistance in Plants
 PUBLICATION DATE:  September 1994
 ENTRY DATE:  April 1995
 EXPIRATION DATE:  
 UPDATE FREQUENCY: 
 CONTACT:  Jane Gates
           Alternative Farming Systems Information Center
           National Agricultural Library
           Room 304, 10301 Baltimore Ave.
           Beltsville, MD  20705-2351
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 DOCUMENT TYPE:  text
 DOCUMENT SIZE:  83k (59 pages)
 
 
 ==============================================================
                                              ISSN:  1052-5378
 United States Department of Agriculture
 National Agricultural Library
 10301 Baltimore Blvd.
 Beltsville, Maryland  20705-2351
 
 Herbicide Tolerance/Resistance in Plants
 April 1991 - March 1994
 
 
 
 
 QB 94-60
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 U.S. Department of Agriculture
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 Public Services Division, Room 111
 Beltsville, Maryland 20705-2351
 
 Herbicide Tolerance/Resistance in Plants
 April 1991 - March 1994
 
 
 
 
 Quick Bibliography Series:  QB 94-60
 Updates QB 91-104
 
 
 342 citations in English from AGRICOLA
 
 
 Raymond Dobert
 Biotechnology Information Center
 
 
 
 
 
 
 
 September 1994
 National Agricultural Library Cataloging Record:
 
 Dobert, Raymond
   Herbicide tolerance/resistance in plants.
   (Quick bibliography series ; 94-60)
   1. Herbicide resistance--Bibliography. 2. Plants, Effect of
 herbicides on--Bibliography. 3. Herbicide resistant crops--
 Bibliography. I. Title.
 aZ5071.N3 no.94-60
 
 
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 Citations in this bibliography are from the National
 Agricultural Library's AGRICOLA database.  An explanation of
 sample journal article, book, and audiovisual citations
 appears below.
 
 JOURNAL ARTICLE:
 
   Citation #                                     NAL Call No.
   Article title.
   Author.  Place of publication:  Publisher.  Journal Title.
   Date.  Volume (Issue).  Pages.  (NAL Call Number).
 
 Example:
   1                             NAL Call No.:  DNAL 389.8.SCH6
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   (8). p.48-50. ill.
 
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   1                        NAL Call No.:  DNAL RM218.K36 1987
   Exploring careers in dietetics and nutrition.
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   Mayo, Cynthia.  Richmond, Va.:  Richmond Public Schools,  
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   Mayo.  1 videocassette (30 min.): sd., col.; 3/4 in. +
   activity packet.
 Herbicide Tolerance/Resistance in Plants
 
 SEARCH STRATEGY
 
 SET    ITEMS   DESCRIPTION
 
 S1       823   HERBICID? (W) (TOLERAN? OR RESISTAN?)
 
 S2       396   S1 AND PY=1991:1999
 
 S3       395   S2/ENG
 
            Herbicide Tolerance/Resistance in Plants
 
 
 1                                NAL Call. No.: 275.29 N272EX
 A 1992 guide for--herbicide use in Nebraska.
 Lincoln, Neb. : The Service; 1992.
 EC - Cooperative Extension Service, University of Nebraska
 (92-130): 51 p.; 1992.  Includes references.
 
 Language:  English
 
 Descriptors: Nebraska; Weed control; Herbicides; Weeds;
 Herbicide resistance; Conservation tillage
 
 
 2                                     NAL Call. No.: 79.8 W41
 Absence of a role for absorption, translocation, and
 metabolism in differential sensitivity of hemp dogbane
 (Apocynum cannabinum) to two pyridine herbicides.
 Orfanedes, M.S.; Wax, L.M.; Liebel, R.A.
 Champaign, Ill. : Weed Science Society of America; 1993 Jan.
 Weed science v. 41 (1): p. 1-6; 1993 Jan.  Includes
 references.
 
 Language:  English
 
 Descriptors: Apocynum cannabinum; Clopyralid; Fluroxypyr;
 Herbicide resistance; Susceptibility; Absorption; Metabolism;
 Translocation; Weeds; Weed control
 
 Abstract:  Hemp dogbane is sensitive to fluroxypyr and
 tolerant to clopyralid. Absorption, translocation, and
 metabolism of clopyralid and fluroxypyr were studied in hemp
 dogbane to determine if differences in these processes could
 be responsible for differential sensitivity. In addition, the
 effect of growth stage on herbicide absorption and
 translocation was evaluated. The 14C-herbicides were applied
 to the adaxial side of a single leaf located near the midpoint
 of hydroponically cultured plants. Uptake of fluroxypyr was
 more rapid than clopyralid. At 72 h after treatment (HAT),
 fluroxypyr and clopyralid absorption was 62 and 38%,
 respectively. Clopyralid was much more mobile than fluroxypyr,
 with 75% of the absorbed 14C from 14C-clopyralid recovered
 outside the treated leaf compared to only 45% for fluroxypyr
 72 HAT. Relative to fluroxypyr, a higher percentage of 14C-
 clopyralid recovered outside the treated leaf translocated
 acropetally, especially when plants were treated during the
 vegetative stage. Treatment during the early reproductive
 stage increased basipetal and reduced acropetal translocation
 relative to the vegetative stage. Neither herbicide was
 metabolized rapidly. Approximately 60 and 90% of the recovered
 14C was attributable to unaltered fluroxypyr and clopyralid,
 respectively, 72 HAT. Some differences in absorption,
 translocation, and metabolism between clopyralid and
 fluroxypyr exist, but they cannot fully account for
 differential sensitivity of hemp dogbane to these two
 herbicides. Differences in activity at the target site may be
 responsible for differential activity of these herbicides on
 hemp dogbane.
 
 
 3                                    NAL Call. No.: SB951.P49
 Absorption and metabolism of clomazone by suspension-cultured
 cells of soybean and velvetleaf.
 Weimer, M.R.; Balke, N.E.; Buhler, D.D.
 Orlando, Fla. : Academic Press; 1992 Jan.
 Pesticide biochemistry and physiology v. 42 (1): p. 43-53;
 1992 Jan.  Includes references.
 
 Language:  English
 
 Descriptors: Glycine max; Abutilon theophrasti; Cell
 suspensions; Cell cultures; Metabolic detoxification;
 Clomazone; Absorption; Metabolism; Oxidation; Metabolites;
 Characterization; Herbicide resistance; Species differences;
 Phytotoxicity; Selectivity; Pharmacokinetics
 
 Abstract:  Clomazone uptake and metabolism were compared in
 soybean and velvetleaf suspension cultured cells utilizing
 either [14C]methylene-clomazone or [14C]carbonyl-clomazone.
 Velvetleaf cells absorbed more clomazone than soybean did.
 Cells of both species accumulated more metabolites when
 treated with [14C]methylene-clomazone than when treated with
 [14C]carbonyl-clomazone. Higher amounts of [14C]metabolites
 were present in the media of cells treated with [14C]carbonyl-
 clomazone than [14C]methylene-clomazone. Differences in uptake
 were due to cellular retention of the benzyl moiety and efflux
 of the heterocyclic moiety after cleavage of clomazone. All
 metabolites produced in soybean and velvetleaf cells were more
 polar than clomazone. No qualitative differences in the
 metabolites produced by soybean and velvetleaf were
 identified. Both soybean and velvetleaf oxidatively cleaved
 the clomazone molecule and subsequently conjugated the benzyl
 moiety with glucose. One of the aglycones was identified as 2-
 chlorobenzylalcohol. Oxidative cleavage of clomazone was a
 major metabolic reaction occurring in both the tolerant
 (soybean) and susceptible (velvetleaf) species.
 
 
 4                                     NAL Call. No.: SD13.C35
 Absorption and translocation of [14C]glyphosate in four woody
 plant species. Green, T.H.; Minogue, P.J.; Brewer, C.H.;
 Glover, G.R.; Gjerstad, D.H. Ottawa, Ont. : National Research
 Council of Canada; 1992 Jun. Canadian journal of forest
 research; Revue canadienne de recherche forestiere v. 22 (6):
 p. 785-789; 1992 Jun.  Includes references.
 
 Language:  English
 
 Descriptors: Southeastern states of U.S.A.; Pinus taeda; Ilex
 vomitoria; Acer rubrum; Quercus rubra; Glyphosate; Tolerance;
 Translocation; Absorption; Leaves; Roots; Stems
 
 Abstract:  Absorption and translocation patterns of radio-
 labelled glyphosate (N-(phosphonomethyl)glycine) were examined
 in four species of woody plants to determine mechanisms of
 herbicide tolerance in species common to the southeastern
 United States. Loblolly pine (Pinus taeda L.) and yaupon (Ilex
 vomitoria (L.) Ait.), both tolerant to the herbicide, absorbed
 significantly less glyphosate than did red maple (Acer rubrum
 L.) or white oak (Quercus alba L.), indicating the importance
 of foliar absorption as a barrier to glyphosate entry.
 Although herbicide absorption was similar between the
 sensitive white oak and the tolerant red maple, white oak
 accumulated more glyphosate in the roots than did red maple,
 indicating that translocation patterns also contribute
 significantly to glyphosate tolerance in some woody species.
 
 
 5                                     NAL Call. No.: 450 P692
 Acetolactate synthase inhibiting herbicides bind to the
 regulatory site. Subramanian, M.V.; Loney-Gallant, V.; Dias,
 J.M.; Mireles, L.C. Rockville, Md. : American Society of Plant
 Physiologists; 1991 May. Plant physiology v. 96 (1): p.
 310-313; 1991 May.  Includes references.
 
 Language:  English
 
 Descriptors: Nicotiana tabacum; Gossypium hirsutum; Mutants;
 Herbicide resistance; Phytotoxicity; Triazole herbicides;
 Sulfonylurea herbicides; Chlorsulfuron; Imazethapyr;
 Imidazolinone herbicides; Ligases; Enzyme inhibitors; Binding
 site; Leucine
 
 Abstract:  Acetolactate synthase from spontaneous mutants of
 tobacco (Nicotiana tabacum; KS-43 and SK-53) and cotton
 (Gossypium hirsutum; PS-3, PSH-91, and DO-2) selected in
 tissue culture for resistance to a triazolopyrimidine
 sulfonanilide showed varying degrees of insensitivity to
 feedback inhibitor(s) valine and/or leucine. A similar feature
 was evident in the enzyme isolated from chlorsulfuron-
 resistant weed biotypes, Kochia scoparia and Stellaria media.
 Dual inhibition analyses of triazolopyrimidine sulfonanilide,
 thifensulfuron, and imazethapyr versus feedback inhibitor
 leucine revealed that the three herbicides were competitive
 with the amino acid for binding to acetolactate synthase from
 wild-type cotton cultures. Acetolactate synthase inhibiting
 herbicides may bind to the regulatory site on the enzyme.
 
 
 6                                     NAL Call. No.: 79.8 W41
 Acifluorfen tolerance in Lycopersicon.
 Ricotta, J.A.; Masiunas, J.B.
 Champaign, Ill. : Weed Science Society of America; 1992 Jul.
 Weed science v. 40 (3): p. 413-417; 1992 Jul.  Includes
 references.
 
 Language:  English
 
 Descriptors: Lycopersicon esculentum; Genotypes; Herbicide
 resistance; Acifluorfen; Absorption; Foliar uptake; Leaves;
 Cuticle; Waxes; Translocation; Metabolism; Ascorbic acid;
 Varietal susceptibility; Chlorophyll
 
 Abstract:  Studies were conducted to determine the mechanism
 of acifluorfen tolerance within the Lycopersicon genus.
 Absorption of 14C-acifluorfen was not correlated with
 tolerance. There was a negative correlation (r = -0.57)
 between absorption 24 h after treatment and wax density. No
 other surface characteristic correlated with absorption. Less
 than 3% of absorbed 14C was translocated and there was no
 metabolism of acifluorfen. All genotypes were susceptible to
 paraquat, and acifluorfen-tolerant genotypes had lower levels
 of ascorbate than susceptible genotypes, implying that free
 radical protectant systems were not involved in tolerance.
 Genotypes varied in amounts of chlorophyll a, chlorophyll b,
 and total chlorophyll but the differences did not correlate to
 acifluorfen tolerance.
 
 
 7                                    NAL Call. No.: SB610.W39
 Addressing real weed science needs with innovations.
 Gressel, J.
 Champaign, Ill. : The Society; 1992 Jul.
 Weed technology : a journal of the Weed Science Society of
 America v. 6 (3): p. 509-525; 1992 Jul.  Literature review. 
 Includes references.
 
 Language:  English
 
 Descriptors: Weeds; Weed control; Agricultural research;
 Herbicides; Herbicide resistance; Pest management; Biological
 control; Biotechnology; Parasitic weeds; Agriculture;
 Literature reviews
 
 
 8                                    NAL Call. No.: SB123.P55
 Advances in achieving the needs for biotechnologically-derived
 herbicide resistant crops.
 Gressel, J.
 New York, N.Y. : John Wiley & Sons, Inc; 1993.
 Plant breeding reviews v. 11: p. 155-198; 1993.  Includes
 references.
 
 Language:  English
 
 Descriptors: Crops; Plant breeding; Herbicide resistance;
 Genes; Genetic engineering; Biotechnology; Cultivars; Weed
 control; Genetic resistance; Literature reviews
 
 
 9                                    NAL Call. No.: QK725.P54
 Agrobacterium mediated transfer of a mutant Arabidopsis
 acetolactate synthase gene confers resistance to chlorsulfuron
 in chicory (Chichorium intybus L.). Vermeulen, A.; Vaucheret,
 H.; Pautot, V.; Chupeau, Y.
 Berlin, W. Ger. : Springer International; 1992.
 Plant cell reports v. 11 (5/6): p. 243-247; 1992.  Includes
 references.
 
 Language:  English
 
 Descriptors: Cichorium intybus; Genetic transformation;
 Herbicide resistance; Chlorsulfuron; Kanamycin; Transgenics;
 Agrobacterium tumefaciens; Arabidopsis thaliana; Gene transfer
 
 Abstract:  Leaf discs of C. intybus were inoculated with an
 Agrobacterium tumefaciens strain harboring a neomycin
 phosphotransferase (neo) gene for kanamycin resistance and a
 mutant acetolactate synthase gene (csr1-1) from Arabidopsis
 thaliana conferring resistance to sulfonylurea herbicides. A
 regeneration medium was optimized which permitted an efficient
 shoot regeneration from leaf discs. Transgenic shoots were
 selected on rooting medium containing 100 mg/l kanamycin
 sulfate. Integration of the csr1-1 gene into genomic DNA of
 kanamycin resistant chicory plants was confirmed by Southern
 blot hybridizations. Analysis of the selfed progenies (S1 and
 S2) of two independent transformed clones showed that
 kanamycin and chlorsulfuron resistances were inherited as
 dominant Mendelian trails. The method described here for
 producing transformed plants will allow new opportunities for
 chicory breeding.
 
 
 10                                      NAL Call. No.: 30 Ad9
 Agronomic improvement in oilseed brassicas.
 Downey, R.K.; Rimmer, S.R.
 San Diego, Calif. : Academic Press; 1993.
 Advances in agronomy v. 50: p. 1-66; 1993.  Includes
 references.
 
 Language:  English
 
 Descriptors: Brassica campestris; Brassica carinata; Brassica
 juncea; Brassica napus; Oilseed plants; Macroeconomics;
 Biotechnology; Crop yield; Cultivars; Genetic improvement;
 Genome analysis; Hybridization; Disease resistance; Herbicide
 resistance; Pest resistance; Yield components; Plant oils;
 Protein content; Seeds; Literature reviews
 
 
 11                                   NAL Call. No.: 64.8 C883
 Agronomic performance of sulfonylurea-resistant transgenic
 flue-cured tobacco grown under field conditions.
 Brandle, J.E.; Miki, B.L.
 Madison, Wis. : Crop Science Society of America, 1961-; 1993
 Jul. Crop science v. 33 (4): p. 847-852; 1993 Jul.  Includes
 references.
 
 Language:  English
 
 Descriptors: Nicotiana tabacum; Transgenic plants; Lines;
 Herbicide resistance; Sulfonylurea herbicides; Agronomic
 characteristics; Genetic resistance; Chlorsulfuron;
 Tribenuron; Phytotoxicity; Crop yield; Crop damage; Gene
 expression; Genetic variation
 
 Abstract:  Field testing of transgenic crops is an essential
 step towards commercialization. This study was conducted to
 assess the agronomic performance of herbicide-resistant
 transgenic tobacco (Nicotiana tabacum L.) lines relative to
 untransformed controls and to evaluate their sensitivity to
 sulfonylurea herbicides in a field situation. Two transgenic
 flue-cured tobacco lines harboring the csr1-1 gene for
 sulfonylurea resistance were evaluated after application of
 three rates of two sulfonylurea herbicides [chlorsulfuron (2-
 chloro-N[(4-methoxy-6-methyl- 1,3,5 triazin-2-yl)
 aminocarbonyl]-aminosulfonyl]-2-thiophenecarboxylate) R9674, a
 2:1 mixture of thifensulfuron (methyl-3-[[4-methoxy-6-methyl-
 1,3,5-triazin-2-yl aminocarbonyl]aminosulfonyl]-2-
 thiophenecarboxy- late) and tribenuron (methyl-2[[[[4-
 methoxy-6-methyl-1,3,5-triazin-2-
 yl]carbonyl]amino]sulfonyl]benzoate)]. We show that one of the
 lines was resistant to 10 g a.i. ha-1 of chlorsulfuron but not
 to 20 g a.i. ha-1 and that both lines were susceptible to DPX-
 R9674. Comparison of transgenics to an untransformed control
 in the absence of herbicide treatment showed that both
 transgenics were lower yielding than tbe controls. This
 impairment of agronomic performance could be attributed to any
 of a number of factors. Resistance to chlorsulfuron was
 adequate, but margins of safety need to be increased before
 any farm level use of these transgenic lines can be
 considered. Selection among lines for maximum expression of
 the transgene and selection or backcrossing to recover the
 parental phenotype may further improve agronomic performance.
 
 
 12                                   NAL Call. No.: SB193.F59
 Alfalfa germplasm with resistance to terbacil.
 Caddel, J.L.; Stritzke, J.F.; Anderson, M.P.; Bensch, C.
 Georgetown, Tx. : American Forage and Grassland Council; 1992.
 Proceedings of the Forage and Grassland Conference v. 1: p.
 162-165; 1992.
 
 Language:  English
 
 Descriptors: Oklahoma; Medicago sativa; Terbacil; Herbicide
 resistance; Germplasm; Selection
 
 
 13                                    NAL Call. No.: 442.8 Z8
 Allelic mutations in acetyl-coenzyme A carboxylase confer
 herbicide tolerance in maize.
 Marshall, L.C.; Somers, D.A.; Dotray, P.D.; Gengenbach, B.G.;
 Wyse, D.L.; Gronwald, J.W.
 Berlin, W. Ger. : Springer International; 1992.
 Theoretical and applied genetics v. 83 (4): p. 435-442; 1992. 
 Includes references.
 
 Language:  English
 
 Descriptors: Zea mays; Structural genes; Alleles; Acetyl-coa
 carboxylase; Mutants; Mutations; Herbicide resistance;
 Haloxyfop; Sethoxydim; Allelism; In vitro selection;
 Inheritance; Semidominance; Enzyme activity
 
 Abstract:  The genetic relationship between acetyl-coenzyme A
 carboxylase (ACCase; EC 6.4.1.2.) activity and herbicide
 tolerance was determined for five maize (Zea mays L.) mutants
 regenerated from tissue cultures selected for tolerance to the
 ACCase-inhibiting herbicides, sethoxydim and haloxyfop.
 Herbicide tolerance in each mutant was inherited as a
 partially dominant, nuclear mutation. Allelism tests indicated
 that the five mutations were allelic. Three distinguishable
 herbicide tolerance phenotypes were differentiated among the
 five mutants. Seedling tolerance to herbicide treatments
 cosegregated with reduced inhibition of seedling leaf ACCase
 activity by sethoxydim and haloxyfop demonstrating that
 alterations of ACCase conferred herbicide tolerance.
 Therefore, we propose that at least three, and possible five,
 new alleles of the maize ACCase structural gene (Acc1) were
 identified based on their differential response to sethoxydim
 and haloxyfop. The group represented by Acc1-S1, Acc1-S2 and
 Acc1-S3 alleles, which had similar phenotypes, exhibited
 tolerance to high rates of sethoxydim and haloxyfop. The Acc1-
 H1 allele lacked sethoxydim tolerance but was tolerant to
 haloxyfop, whereas the Acc1-H2 allele had intermediate
 tolerance to sethoxydim but was tolerant to haloxyfop.
 Differences in tolerance to the two herbicides among mutants
 homozygous for different Acc1 alleles suggested that sites on
 ACCase that interact with the different herbicides do not
 completely overlap. These mutations in maize ACCase should
 prove useful in characterization of the regulatory role of
 ACCase in fatty acid biosynthesis and in development of
 herbicide-tolerant maize germplasm.
 
 
 14                                   NAL Call. No.: SB610.W39
 Alternatives for control of paraquat tolerant American black
 nightshade (Solanum americana).
 Bewick, T.A.; Stall, W.M.; Kostewicz, S.R.; Smith, K.
 Champaign, Ill. : The Society; 1991 Jan.
 Weed technology : a journal of the Weed Science Society of
 America v. 5 (1): p. 61-65; 1991 Jan.  Includes references.
 
 Language:  English
 
 Descriptors: Lycopersicon esculentum; Weed control; Solanum
 Americanum; Herbicide resistant weeds; Paraquat; Herbicide
 resistance; Biotypes; Chemical control; Diquat; Oxyfluorfen;
 Acifluorfen; Tridiphane; Pyridate; Chelates; Herbicide
 mixtures; Application rates
 
 
 15                                   NAL Call. No.: QH301.A76
 Alternatives to triazines for weed control in forest
 nurseries. Mason, W.L.
 Wellesbourne, Warwick : The Association of Applied Biologists;
 1992. Aspects of applied biology (29): p. 149-155; 1992.  In
 the series analytic: Vegetation management in forestry,
 amenity and conservation areas. Paper presented at the
 conference of the Association, April 7-9, 1992, University of
 York, England.  Includes references.
 
 Language:  English
 
 Descriptors: Great Britain; Forest nurseries; Herbicide
 resistance; Herbicides; Metazachlor; Site factors; Triazines;
 Weed control
 
 
 16                                    NAL Call. No.: 79.8 W41
 Amitrole, triazine, substituted urea, and metribuzin
 resistance in a biotype of rigid ryegras (Lolium rigidum).
 Burnet, M.W.M.; Hildebrand, O.B.; Holtum, J.A.M.; Powles, S.B.
 Champaign, Ill. : Weed Science Society of America; 1991 Jul.
 Weed science v. 39 (3): p. 317-323; 1991 Jul.  Includes
 references.
 
 Language:  English
 
 Descriptors: Lolium rigidum; Biotypes; Herbicide resistance;
 Herbicide resistant weeds; Amitrole; Atrazine; Cross
 resistance; Simazine; Cyanazine; Propazine; Ametryn;
 Prometryn; Chlorotoluron; Isoproturon; Metoxuron; Diuron;
 Fluometuron; Metribuzin; Methazole; Resistance mechanisms;
 Photosynthesis
 
 Abstract:  A biotype of rigid ryegrass (Lolium rigidum G.
 LOLRI) has become resistant to amitrole and atrazine after 10
 yr of exposure to a mixture of these herbicides. Resistance
 has also been demonstrated to the chloro-s-triazines:
 simazine, cyanazine, propazine; the
 methylthio-s-triazines: ametryn, prometryn; the substituted
 ureas: chlortoluron, isoproturon, metoxuron, diuron,
 fluometuron, methazole; and the triazinone herbicide
 metribuzin. The biotype remains susceptible to chlorsulfuron,
 metsulfuron, sulfometuron, sethoxydim, diclofop, fluazifop,
 glyphosate, carbetamide, and oxyfluorfen. Inhibition of oxygen
 evolution by atrazine, diuron, and metribuzin was similar in
 thylakoids isolated from both resistant and susceptible
 biotypes. Therefore, resistance to the photosystem II
 inhibitors is not caused by an alteration of the target site
 of these herbicides. Resistant plants treated with a 3-h pulse
 of 0.12 millimoles chlortoluron recover photosynthetic
 activity more rapidly than susceptible plants. This suggests
 that the basis for resistance is enhanced metabolism or
 sequestration of the herbicide within the leaf.
 
 
 17                                 NAL Call. No.: QH431.A1G43
 Analysis of the effects of herbicides on pea seedlings and
 calluses, and the isolation of herbicide-resistant callus
 lines and regenerant plants. Ezhova, T.A.; Tikhvinskaya, N.S.;
 Petrova, T.V.; Bagrova, A.M.; Vasil'ev, I.R.; Matorin, D.N.;
 Gostimskii, S.A.
 New York, N.Y. : Consultants Bureau; 1991 May.
 Soviet genetics v. 26 (11): p. 1317-1322; 1991 May. 
 Translated from: Genetika, v. 26 (11), 1990, p. 2012-2019.
 (QH431.A1G4).  Includes references.
 
 Language:  English; Russian
 
 Descriptors: Pisum sativum; Mutants; Induced mutations; In
 vitro selection; Artificial selection; Seedlings; Callus;
 Tissue culture; Herbicide resistance; Atrazine; Dinoseb;
 Glyphosate; Diuron; Inheritance; Heritability
 
 Abstract:  The effects of atrazine, dinoseb, diuron, and
 glyphosate on pea seedlings and prolonged cultures of
 photoheterotrophic calluses were compared. Herbicides were
 found to have similar effects on the growth of seedlings and
 the survival of calluses. Cultivation of calluses on selective
 media containing threshold concentrations of herbicide
 resulted in the isolation of callus lines resistant to the
 herbicide used (42, 13, 10, and 8 lines resistant to atrazine,
 dinoseb, diuron, and glyphosate respectively were obtained).
 Regenerant plants of the R0 and R1 generations were obtained
 from photosynthesis-blocking herbicide-resistant calluses.
 Delayed fluorescence analysis showed that resistance to
 photosynthesis-blocking herbicide in the callus lines selected
 was not only retained when plants were regenerated, but was
 also passed on to the subsequent seed generation (R1),
 demonstrating its genetic nature. Resistance to atrazine in
 two R1 regenerant lines was shown to result from reductions in
 the sensitivity of electron transfer to the acceptor component
 of photosystem II, which is presumably due to alterations in
 the herbicide binding protein D-1.
 
 
 18                                 NAL Call. No.: SB610.2.B74
 Annual ryegrass: an abundance of resistance, a plethora of
 mechanisms. Holtum, J.A.M.; Powles, S.B.
 Surrey : BCPC Registered Office; 1991.
 Brighton Crop Protection Conference-Weeds v. 3: p. 1071-1078;
 1991.  Meeting held November 18-21, 1991, Brighton, England. 
 Includes references.
 
 Language:  English
 
 Descriptors: Australia; Lolium rigidum; Biotypes; Herbicide
 resistance; Inheritance; Phenoxypropionic herbicides;
 Chlorsulfuron
 
 
 19                                    NAL Call. No.: 381 B522
 Apparent destabilization of the S1 state related to herbicide
 resistance in a cyanobacterium mutant.
 Kirilovsky, D.; Ducruet, J.M.; Etienne, A.L.
 Amsterdam : Elsevier Science Publishers; 1991 Sep27.
 Biochimica et biophysica acta : International journal of
 biochemistry and biophysics v. 1060 (1): p. 37-44; 1991 Sep27. 
 Includes references.
 
 Language:  English
 
 Descriptors: Metribuzin; Cyanobacteria; Mutants; Photosystem
 ii; Herbicide resistance
 
 Abstract:  In this work we describe a new phenotype of
 herbicide-resistant mutants. We have selected and
 characterized several metribuzin resistant mutants from
 Synechocystis 6714. We found that an increase in metribuzin
 resistance involved a cross-resistance with other herbicides.
 Therefore, the mutants could be classified in three groups:
 (1) metribuzin resistant; (2) atrazine and metribuzin
 resistant; (3) DCMU, atrazine and metribuzin resistant.
 Mutants which did not present cross-resistance were up to 25-
 fold more resistant to metribuzin than the wild type. We have
 studied the electron transfer properties of Photosystem II in
 these mutants using several techniques (oxygen emission,
 fluorescence, and thermoluminescence measurements). They
 presented modifications in the electron transfer between QA
 and QB, as was generally observed in most herbicide-resistant
 mutants previously studied. However, unexpectedly, one of
 these mutants, M30, presented a modified oscillatory pattern
 of oxygen emission. After dark adaptation the maximum of the
 oscillation was shifted by one flash. The matrix analysis
 indicated that the shifted maximum of the oxygen sequence
 corresponded to an increased S0 concentration in the dark-
 adapted state. In whole cells S0 and S1 are in equilibrium.
 This equilibrium is shifted in favor of S0 in the M30 mutant.
 The mutation renders the S-states more accessible to cell
 reductants.
 
 
 20                                     NAL Call. No.: S77.I56
 Applications of biotechnology to crop improvement.
 Warnes, D.D.; Somers, D.A.
 Morris, Minn. : The Station; 1992.
 Innovations - University of Minnesota, West Central Experiment
 Station v. 2 (1): p. 5; 1992.
 
 Language:  English
 
 Descriptors: Plant breeding; Genetic engineering; Genetic
 resistance; Herbicide resistance; Pest resistance
 
 
 21                                    NAL Call. No.: 79.8 W41
 Applications of molecular biology in weed science.
 Dyer, W.E.
 Champaign, Ill. : Weed Science Society of America; 1991 Jul.
 Weed science v. 39 (3): p. 482-488; 1991 Jul.  Paper presented
 at the "Symposium on New Techniques adn Advances in Weed
 Physiology and Molecular Biology," February 6, 1991,
 Louisville, Kentucky.  Includes references.
 
 Language:  English
 
 Descriptors: Weeds; Weed biology; Molecular biology;
 Transgenics; Laboratory methods; Restriction mapping;
 Restriction fragment length polymorphism; Cloning; Dna
 hybridization; Gene transfer; Electrophoresis; Gene
 expression; Genome analysis; Genetic analysis
 
 Abstract:  Rapid strides are being made in understanding the
 fundamental regulation of plant growth, development, and
 responses to the environment due to recent advances in
 molecular biology. Current questions in weed science such as
 herbicide mechanisms of action, biodegradation, and mechanisms
 of weed resistance are equally approachable using such
 methodology. Efforts to introduce herbicide resistance into
 agronomically important crops are possible because of
 successful isolation and transfer of genes. Investigations of
 weed survival and competitive strategies based on
 developmental processes, such as seed dormancy, are currently
 underway using techniques designed to monitor and characterize
 differential gene expression. Molecular methodology also plays
 a key role in taxonomic studies of weed populations using
 restriction fragment length polymorphism (RFLP) mapping. The
 future potential for these and other techniques such as
 nucleic acid hybridization, polymerase chain reaction (PCR),
 gene transfer, and the use of transgenic plants is described.
 
 
 22                                   NAL Call. No.: SB951.P47
 An association between triazine resistance and powdery mildew
 resistance in Epilobium ciliatum and Senecio vulgaris.
 Clay, D.V.; Nash, C.; Bailey, J.A.
 Essex : Elsevier Applied Science Publishers; 1991.
 Pesticide science v. 33 (2): p. 189-196; 1991.  Includes
 references.
 
 Language:  English
 
 Descriptors: Uk; Epilobium; Senecio vulgaris; Atrazine;
 Herbicide resistance; Disease resistance; Mildews; Erysiphe
 cichoracearum; Sphaerotheca; Susceptibility; Relationships;
 Types
 
 Abstract:  The response of four naturally, occurring biotypes
 of Epilobium ciliatum and four sources of Senecio vulgaris to
 the herbicide atrazine were compared with their susceptibility
 to the powdery mildews Sphaerotheca epilobii and Erysiphe
 cichoracearum. Biotypes that were resistant to atrazine were
 also resistant to mildew. Mechanisms that night explain the
 association between atrazine resistance and mildews resistance
 are discussed, along with possible implications of these
 findings for farmland ecology, an for the production of
 herbicide- and mildew-resistant crop plants.
 
 
 23                                    NAL Call. No.: 450 P692
 Atrazine resistance in a velvetleaf (Abutilon theophrasti)
 biotype due to enhanced glutathione S-transferase activity.
 Anderson, M.P.; Gronwald, J.W.
 Rockville, Md. : American Society of Plant Physiologists; 1991
 May. Plant physiology v. 96 (1): p. 104-109; 1991 May. 
 Includes references.
 
 Language:  English
 
 Descriptors: Maryland; Minnesota; Abutilon theophrasti;
 Biotypes; Atrazine; Herbicide resistance; Glutathione
 transferase; Enzyme activity; Genetic resistance
 
 Abstract:  We previously reported that a velvetleaf (Abutilon
 theophrasti Medic) biotype found in Maryland was resistant to
 atrazine because of an enhanced capacity to detoxify the
 herbicide via glutathione conjugation (JW Gronwald, Andersen
 RN, Yee C [1989] Pestic Biochem Physiol 34: 149-163). The
 biochemical basis for the enhanced atrazine conjugation
 capacity in this biotype was examined. Glutathione levels and
 glutathione S-transferase activity were determined in extracts
 from the atrazine-resistant biotype and an atrazine-
 susceptible or "wild-type" velvetleaf biotype. In both
 biotypes, the highest concentration of glutathione
 (approximately 600 nanomoles per gram fresh weight) was found
 in leaf tissue. However, no significant differences were found
 in glutathione levels in roots, stems, or leaves of either
 biotype. In both biotypes, the highest concentration of
 glutathione S-transferase activity measured with 1-chloro-2,4-
 dinitrobenzene or atrazine as substrate was in leaf tissue.
 Glutathione S-transferase measured with 1-chloro-2,4-
 dinitrobenzene as substrate was 40 and 25% greater in leaf and
 stem tissue, respectively, of the susceptible biotype compared
 to the resistant biotype. In contrast, glutathione S-
 transferase activity measured with atrazine as substrate was
 4.4- and 3.6-fold greater in leaf and stem tissue,
 respectively, of the resistant biotype. Kinetic analyses of
 glutathione S-transferase activity in leaf extracts from the
 resistant and susceptible biotypes were performed with the
 substrates glutathione, 1-chloro-2,4-dinitrobenzene, and
 atrazine. There was little or no change in apparent Km values
 for glutathione, atrazine, or 1-chloro-2,4-dinitrobenzene.
 However, the Vmax for glutathione and atrazine were
 approximately 3-fold higher in the resistant biotype than in
 the susceptible biotype. In contrast, the Vmax for 1-
 chloro-2,4-dinitrobenzene was 30% lower in the resistant
 biotype. Leaf glutathione S-transferase isozymes that exhibit
 activity with atrazine and 1-chloro-2,4-dinitrobenzene were
 separated by fast protein liquid (anion-exchange)
 chromatography.  The susceptible biotype, had three peaks
 exhibiting activity with atrazine and the resistant biotype
 had two.  The two peaks of glutathione S-transferase activity
 with atrazine from the resistant biotype coeluted with two of
 the peaks from the susceptible biotype, but peak height was
 three- to fourfold greater in the resistant biotype, in both
 biotypes, two of the peaks that exhibit glutathione S-
 transferase activity with atrazine also exhibited activity
 with 1-chloro-2,4-dinitrobenzene, with the peak height being
 greater in the susceptibele biotype.  The resulsts indicated
 that atraine glutathionse S-trasferase activity for atrazine
 resistant in the velvetleaf biotype from Maryland is due to
 enhanced glutathione S-transferase activity foratrazine in
 leaf and stem tissue which results in an enhanced capacity to
 detoxify the herbicide via glutathione conjugation.
 
 
 24                                   NAL Call. No.: 79.8 W412
 Attempts to transfer paraquat resistance from barley grass
 (Hordeum glaucum Steud.) to barley and wheat.
 Islam, A.K.M.R.; Australia; Powles, S.B.
 Oxford : Blackwell Scientific Publications; 1991 Dec.
 Weed research v. 31 (6): p. 395-399; 1991 Dec.  Includes
 references.
 
 Language:  English
 
 Descriptors: Hordeum vulgare; Triticum aestivum; Selection
 criteria; Herbicide resistance; Paraquat; Hybridization;
 Hordeum glaucum; Transfer
 
 
 25                                   NAL Call. No.: QP601.M49
 The bar gene as selectable and screenable marker in plant
 engineering. D'Halluin, K.; Block, M. de; Denecke, J.;
 Janssens, J.; Leemans, J.; Reynaerts, A.; Botterman, J.
 San Diego, Calif. : Academic Press; 1992.
 Methods in enzymology (216): p. 397-414; 1992.  In the series
 analytic: Recombinant DNA (part G) / edited by R. Wu. 
 Includes references.
 
 Language:  English
 
 Descriptors: Plants; Bilanafos; Herbicide resistance; Reporter
 genes; Marker genes; Genetic transformation; Plant breeding;
 Molecular biology; Tissue cultures
 
 
 26                                    NAL Call. No.: 79.8 W41
 Basis of differential tolerance of two corn hybrids (Zea mays)
 to metolachlor. Cottingham, C.K.; Hatzios, K.K.
 Champaign, Ill. : Weed Science Society of America; 1992 Jul.
 Weed science v. 40 (3): p. 359-363; 1992 Jul.  Includes
 references.
 
 Language:  English
 
 Descriptors: Zea mays; Hybrids; Herbicide resistance;
 Metolachlor; Varietal susceptibility; Enzyme activity;
 Glutathione transferase; Metabolic detoxification; Absorption;
 Translocation; Pharmacokinetics; Phytotoxicity; Crop damage
 
 Abstract:  Greenhouse and laboratory studies were conducted to
 determine the basis of differential response of two corn
 hybrids to the chloroacetanilide herbicide metolachlor. In
 greenhouse experiments, metolachlor at 6.7 kg ha-1 reduced the
 height of the susceptible 'Northrup-King 9283' corn by 53%
 relative to untreated controls and caused extensive visible
 injury 14 d after treatment. Under the same conditions, the
 height of metolachlor-treated 'Cargill 7567' corn seedlings
 was reduced by only 18% without any visible herbicide injury.
 The 14C-metolachlor was more rapidly absorbed by the emerging
 shoot of the metolachlor-susceptible hybrid, Northrup-King
 9283. Thus, differential metolachlor tolerance may be due in
 part to processes at the level of herbicide uptake. Metabolism
 experiments revealed that both hybrids were able to conjugate
 14C-metolachlor with glutathione at similar rates. However,
 glutathione S-transferase activity increased earlier during
 seedling development and reached higher activities in the
 metolachlor-tolerant hybrid, Cargill 7567.
 
 
 27                                    NAL Call. No.: QH442.B5
 Bialaphos treatment of transgenic rice plants expressing a bar
 gene prevents infection by the sheath blight pathogen
 (Rhizoctonia solani). Uchimiya, H.; Iwata, M.; Nojirl, C.;
 Samarajeewa, P.K.; Takamatsu, S.; Ooba, S.; Anzai, H.;
 Christensen, A.H.; Quail, P.H.; Toki, S.
 New York, N.Y. : Nature Publishing,; 1993 Jul.
 Bio/technology v. 11 (7): p. 835-836; 1993 Jul.  Includes
 references.
 
 Language:  English
 
 Descriptors: Oryza sativa; Rhizoctonia solani; Transgenic
 plants; Genetic transformation; Disease resistance;
 Glyphosate; Herbicide resistance; Blight; Structural genes;
 Acyltransferases
 
 
 28                                 NAL Call. No.: QD415.A1B58
 Biochemcial characterization of tobacco mutants resistant to
 azole fungicides and herbicides.
 Schaller, H.; Maillot-Vernier, P.; Gondet, L.; Belliard, G.;
 Benveniste, P. London : Portland Press; 1993 Nov.
 Transactions v. 21 (4): p. 1052-1057; 1993 Nov.  Includes
 references.
 
 Language:  English
 
 Descriptors: Nicotiana tabacum; Mutants; Conazole fungicides;
 Imidazolinone herbicides; Fungicide tolerance; Herbicide
 resistance
 
 
 29                                 NAL Call. No.: SB950.9.C44
 Biochemical basis of herbicide resistance.
 Vaughn, K.C.; Duke, S.O.
 Berlin, W. Ger. : Springer-Verlag; 1991.
 Chemistry of plant protection v. 7: p. 141-169; 1991.  In the
 series analytic: Herbicide resistance--brassinosteroids,
 gibberellins, plant growth regulators / edited by W. Ebing. 
 Literature review.  Includes references.
 
 Language:  English
 
 Descriptors: Herbicide resistant weeds; Biotypes; Herbicide
 resistance; Resistance mechanisms; Glyphosate; Sulfonylurea
 herbicides; Imidazolinone herbicides; Glufosinate; Triazine
 herbicides; Paraquat; Dinitroaniline herbicides; Mcpa; 2,4-d;
 Mode of action; Biochemical pathways; Enzyme inhibitors;
 Biosynthesis; Amino acids; Photosynthesis; Mitosis; Cell
 walls; Literature reviews
 
 
 30                             NAL Call. No.: SB957.R474 1991
 Biochemical mechanisms of resistance to photosystem II
 herbicides. Rensen, J.J.S. van; Vos, O.J. de
 London : Published for SCI by Elsevier Applied Science; 1991.
 Resistance '91, Achievement and Developments in Combating
 Pesticide Resistance / edited by Ian Denholm, Alan L.
 Devonshire, and Derek W. Hollomon. p. 251-261; 1991. 
 Proceedings of the SCI Symposium "Resistance '91: Achievements
 and Developments in Combating Pesticide Resistance," 15-17
 July 1991, Rothamsted Experimental Station, Harpenden, UK. 
 Includes references.
 
 Language:  English
 
 Descriptors: Photosystem ii; Herbicide resistance;
 Photoinhibition
 
 
 31                                 NAL Call. No.: QH442.G4522
 Biotech fix for African crops held hostage to profit motive.
 Conroy, D.
 Washington, D.C. : King Pub. Group; 1993 Feb17.
 Biotech daily v. 2 (124): p. 3; 1993 Feb17.
 
 Language:  English
 
 Descriptors: Africa; Herbicide resistance; Genetic
 engineering; Food crops; Food supply
 
 
 32                                    NAL Call. No.: QH442.B5
 Biotechnology in the food industry.
 Beck, C.I.; Ulrich, T.
 New York, N.Y. : Nature Publishing Company; 1993 Aug.
 Bio/technology v. 11 (8): p. 895-902; 1993 Aug.  Includes
 references.
 
 Language:  English
 
 Descriptors: Food crops; Plant breeding; Genetic engineering;
 Biotechnology; Food quality; Food processing quality; Genetic
 resistance; Herbicide resistance; Plant development
 
 
 33                                    NAL Call. No.: 79.8 W41
 A biotype of hare barley (Hordeum leporinum) resistant to
 paraquat and diquat. Tucker, E.S.; Powles, S.B.
 Champaign, Ill. : Weed Science Society of America; 1991 Apr.
 Weed science v. 39 (2): p. 159-162; 1991 Apr.  Includes
 references.
 
 Language:  English
 
 Descriptors: Victoria; Hordeum murinum subsp. leporinum;
 Biotypes; Herbicide resistance; Paraquat; Diquat; Sethoxydim;
 Fluazifop; Glyphosate; Cross resistance; Dry matter
 accumulation; Growth rate; Survival; Weed biology
 
 Abstract:  A biotype of the annual grass weed hare barley
 infesting an alfalfa field with a 24-yr history of the use of
 the bipyridylium herbicides paraquat and diquat, was
 investigated for resistance to these herbicides. Rates of up
 to 800 g ai ha-1 of each herbicide caused no mortality in the
 hare barley plants from this field. The same species,
 collected from an adjacent pasture field with no history of
 bipyridylium herbicide application, exhibited LD50's of 57 and
 160 g ai ha-1 for paraquat and diquat, respectively. Tiller
 numbers and dry matter production in the biotype from the
 alfalfa field were not affected by the normal rate recommended
 for both herbicides. These results clearly show that hare
 barley from the alfalfa field is resistant to paraquat and
 diquat. Both biotypes were equally sensitive to fluazifop,
 glyphosate, and sethoxydim.
 
 
 34                                      NAL Call. No.: A00035
 Breakthrough should lead to higher wheat yields.
 Summit, N.J. : CTB International Pub. Co; 1992 Jun04.
 Biotechnology news v. 12 (14): p. 1-2; 1992 Jun04.
 
 Language:  English
 
 Descriptors: Triticum aestivum; Genetic engineering;
 Micromanipulation; Herbicide resistance
 
 
 35                                      NAL Call. No.: SB1.H6
 Buffalograss tolerance to postemergence herbicides.
 McCarty, L.B.; Colvin, D.L.
 Alexandria, Va. : American Society for Horticultural Science;
 1992 Aug. HortScience v. 27 (8): p. 898-899; 1992 Aug. 
 Includes references.
 
 Language:  English
 
 Descriptors: Buchloe dactyloides; Lawns and turf; Weed
 control; Chemical control; 2,4-d; Dicamba; Bentazone;
 Mecoprop; Metsulfuron; Quinclorac; Imazaquin; Diclofop;
 Triclopyr; Atrazine; Asulam; Sethoxydim; Msma; Sulfometuron;
 Herbicide resistance
 
 Abstract:  Buffalograss [Buchloe dactyloides (Nutt.) Engelm.]
 is a turfgrass species traditionally adapted to low-rainfall
 areas that may incur unacceptable weed encroachment when grown
 in higher rainfall areas such as Florida. An experiment was
 performed to evaluate the tolerance of two new buffalograss
 cultivars, 'Oasis' and 'Prairie', to postemergence herbicides
 commonly used for grass, broadleaf, and sedge weed control.
 Twenty to 40 days were required for each cultivar to recover
 from treatment with asulam, MSMA, and sethoxydim (2.24, 2.24,
 and 0.56 kg.ha-1, respectively). Other herbicides used for
 postemergence grass weed control (metsulfuron, quinclorac, and
 diclofop at 0.017, 0.56, and 1.12 kg.ha-1, respectively) did
 not cause unacceptable buffalograss injury. Herbicides used
 for postemergence broadleaf weed control, triclopyr, 2,4-D,
 sulfometuron, dicamba (0.56, 1.12, 0.017, and 0.56 kg.ha-1,
 respectively), and a three-way combination of 2,4-D + dicamba
 + mecoprop (1.2 + 0.54 + 0.13 kg.ha-1), caused 20 to 30 days
 of unacceptable or marginally acceptable turfgrass quality,
 while 20 days were required for 'Prairie' buffalograss to
 recover from atrazine treatments. 'Oasis' buffalograss did not
 fully recover from 2,4-D or 2,4-D + dicamba + mecoprop through
 40 days after treatment. Herbicides used for postemergence
 sedge control, bentazon and imazaquin, caused slightly
 reduced, but acceptable, levels of turf quality in both
 cultivars throughout the experiment.
 
 
 36                        NAL Call. No.: TP248.27.P55P53 1991
 Cell selection.
 Loh, W.H.T.
 Oxford : Pergamon Press; 1992.
 Plant biotechnology : comprehensive biotechnology, second
 supplement / volume editors, Michael W. Fowler & Graham S.
 Warren; editor-in-chief, Murray Moo-Young. p. 33-44; 1992. 
 Literature review.  Includes references.
 
 Language:  English
 
 Descriptors: Plants; Mutants; Induced mutations; In vitro
 selection; Herbicide resistance; Salt tolerance; Metal
 tolerance; Heavy metals; Disease resistance; Tissue culture;
 Cell culture; Literature reviews
 
 
 37                                  NAL Call. No.: SB123.P535
 Characterization of a spontaneous rapeseed mutant tolerant to
 sulfonylurea and imidazolinone herbicides.
 Magha, M.I.; Guerche, P.; Bregeon, M.; Renard, M.
 Berlin : P. Parey, 1986-; 1993 Sep.
 Plant breeding; Zeitschrift fur Pflanzenzuchtung v. 111 (2):
 p. 132-141; 1993 Sep.  Includes references.
 
 Language:  English
 
 Descriptors: Brassica napus; Mutants; Mutations; Structural
 genes; Oxo-acid-lyases; Dominance; Herbicide resistance;
 Chlorsulfuron; Triasulfuron; Metsulfuron; Imazamethabenz
 
 
 38                                    NAL Call. No.: 79.8 W41
 Characterization of acifluorfen tolerance in selected
 somaclones of eastern black nightshade (Solanum ptycanthum).
 Yu, C.Y.; Masiunas, J.B.
 Champaign, Ill. : Weed Science Society of America; 1992 Jul.
 Weed science v. 40 (3): p. 408-412; 1992 Jul.  Includes
 references.
 
 Language:  English
 
 Descriptors: Solanum; Herbicide resistant weeds; Acifluorfen;
 Somaclonal variation; Herbicide resistance; Absorption;
 Translocation; Metabolism; Metabolic detoxification; Cross
 resistance; Diquat; Oxyfluorfen; Paraquat
 
 Abstract:  Acifluorfen tolerance in eastern black nightshade
 somaclones was characterized in two experiments. One
 experiment determined the involvement of absorption,
 translocation, and metabolism in acfiluorfen tolerance. Less
 than 6% of the applied 14C-acifluorfen was absorbed. There
 were no differences in acifluorfen absorption between
 susceptible and tolerant somaclones. More 14C-acifluorfen was
 translocated in the susceptible than the tolerant somaclones.
 The susceptible somaclone did not metabolize acifluorfen while
 some somaclones (i.e., EBN-3A) metabolized 14C-acifluorfen. A
 second experiment determined the tolerance of the somaclones
 to oxyfluorfen, diquat, and paraquat. Most acifluorfen-
 tolerant somaclones were tolerant to oxyfluorfen but were
 susceptible to diquat and paraquat. One somaclone, EBN-3A, was
 extremely tolerant to acifluorfen, paraquat, and diquat.
 
 
 39                                   NAL Call. No.: SB957.R47
 Characterization of resistance to atrazine in a velvetleaf
 (Abutilon theophrasti Medik.) biotype from Wisconsin.
 Gray, J.A.; Stoltenberg, D.E.; Balke, N.E.
 East Lansing, Mich. : Pesticide Research Center, Michigan
 State University,; 1993.
 Resistant pest management v. 5 (2): p. 17; 1993.
 
 Language:  English
 
 Descriptors: Wisconsin; Cabt; Abutilon theophrasti; Herbicide
 resistant weeds; Biotypes; Atrazine; Herbicide resistance
 
 
 40                                    NAL Call. No.: 442.8 Z8
 Characterization of transgenic sulfonylurea-resistant flax
 (Linum usitatissimum).
 McSheffrey, S.A.; McHughen, A.; Devine, M.D.
 Berlin, W. Ger. : Springer International; 1992.
 Theoretical and applied genetics v. 84 (3/4): p. 480-481;
 1992.  Includes references.
 
 Language:  English
 
 Descriptors: Linum usitatissimum; Arabidopsis thaliana;
 Agrobacterium tumefaciens; Genetic transformation;
 Transgenics; Gene transfer; Ligases; Structural genes; Enzyme
 activity; Herbicide resistance; Chlorsulfuron; Metsulfuron;
 Segregation; Inheritance; Line differences; Roots; Growth
 
 Abstract:  Fourteen transgenic flax (Linum usitatissimum)
 lines, carrying a mutant Arabidopsis acetolactate synthase
 (ALS) gene selected for resistance to chlorsulfuron, were
 characterized for resistance to two sulfonylurea herbicides.
 Progeny of 10 of the 14 lines segregated in a ratio of 3
 resistant to 1 susceptible, indicating a single insertion.
 Progeny of 1 line segregated in a 15:1 ratio, indicating two
 insertions of the ALS gene at independent loci. Progeny from 3
 lines did not segregate in a Mendelian fashion and were likely
 the products of chimeric shoots. Resistance to chlorsulfuron
 was stably inherited in all lines. At the enzyme level, the
 transgenic lines were 2.5 to more than 60 times more resistant
 to chlorsulfuron than the parental lines. The transgenic lines
 were 25-260 times more resistant to chlorsulfuron than the
 parental lines in root growth experiments and demonstrated
 resistance when grown in soil treated with 20 g ha-1
 chlorsulfuron. The lines demonstrated less resistance to
 metsulfuron methyl; in root growth experiments, the transgenic
 lines were only 1.6-4.8 times more resistant to metsulfuron
 methyl than the parental lines. Resistance was demonstrated in
 the field at half (2.25 g ha-1) and full (4.5 g ha-1) rates of
 metsulfuron methyl.
 
 
 41                                   NAL Call. No.: SB951.P49
 Chlorsulfuron inhibition of phloem translocation in
 chlorsulfuron-resistant and -susceptible Arabidopsis thaliana.
 Hall, L.M.; Devine, M.D.
 Orlando, Fla. : Academic Press; 1993 Feb.
 Pesticide biochemistry and physiology v. 45 (2): p. 81-90;
 1993 Feb.  Includes references.
 
 Language:  English
 
 Descriptors: Chlorsulfuron; Phloem loading; Inhibition;
 Arabidopsis thaliana; Types; Herbicide resistance;
 Susceptibility; Uptake mechanisms; Sucrose; Plasma membranes;
 Microsomes; Enzymes; Adenosinetriphosphatase; Enzyme activity;
 Protein content
 
 Abstract:  The herbicide chlorsulfuron is not translocated
 readily in plants because of an inhibitory effect on phloem
 translocation. More chlorsulfuron was translocated in a
 chlorsulfuron-resistant (R) biotype of Arabidopsis thaliana
 than in a susceptible (S) biotype, indicating that the effect
 on translocation is secondary to inhibition of ALS, the
 primary site of action of the herbicide. The R biotype did not
 different from the S biotype in its ability, to translocate
 exogenously applied sucrose: however, translocation of
 exogenously applied sucrose following chlorsulfuron treatment
 was greater in the R biotype than in the S biotype.
 Chlorsulfuron pretreatment inhibited rapid sucrose uptake into
 leaf discs by 41% in the S biotype but by only 17% in the R
 biotype. This result suggests that chlorsulfuron inhibits
 phloem transport by restricting sucrose uptake into the
 phloem. Purified plasma membrane preparations extracted from
 the two biotypes following chlorsulfuron treatment did not
 differ in H+ -ATPase activity or total plasmalemma protein
 content. Possible alternative mechanisms by which
 chlorsulfuron may inhibit phloem transport are discussed.
 
 
 42                                    NAL Call. No.: 79.8 W41
 Chlorsulfuron-resistant sugarbeet: cross-resistance and
 physiological basis of resistance.
 Hart, S.E.; Saunders, J.W.; Penner, D.
 Champaign, Ill. : Weed Science Society of America; 1992 Jul.
 Weed science v. 40 (3): p. 378-383; 1992 Jul.  Includes
 references.
 
 Language:  English
 
 Descriptors: Beta vulgaris; Herbicide resistance;
 Chlorsulfuron; Cross resistance; Chlorimuron; Imidazolinone
 herbicides; Sulfonylurea herbicides; Enzyme inhibitors; Oxo-
 acid-lyases; Enzyme activity; Absorption; Metabolism
 
 Abstract:  Greenhouse and laboratory studies were conducted to
 determine the extent of cross-resistance of chlorsulfuron-
 resistant sugarbeet (CR1-B) to other herbicides that inhibit
 acetolactate synthase (ALS) and to determine the physiological
 basis of resistance. Cross-resistance to metsulfuron,
 imazaquin, and imazethapyr was not evident, while only
 marginal cross-resistance was observed to triasulfuron, DPX-
 L5300, and nicosulfuron. CR1-B was moderately resistant to
 chlorsulfuron and chlorimuron and was highly cross-resistant
 to thifensulfuron and primisulfuron. Further greenhouse
 studies demonstrated that CR1-B was not significantly injured
 by thifensulfuron and primisulfuron applied at or exceeding
 the field use rate. Studies with 14C-primisulfuron showed that
 differential absorption or metabolism of primisulfuron could
 not account for the observed resistance. ALS enzyme assays
 showed that the CR1-B ALS enzyme activity was 66, 26, and 13
 times less sensitive to chlorsulfuron, thifensulfuron, and
 primisulfuron inhibition, respectively, compared to ALS enzyme
 extracted from sensitive sugarbeets. An altered ALS enzyme,
 which is less sensitive to sulfonylurea herbicide inhibition,
 appears to be the physiological basis of resistance.
 
 
 43                                   NAL Call. No.: SD112.F67
 Clonal variation in tolerance to hexazinone.
 Borough, C.; Jamieson, D.
 Rotorua : The Institute; 1991.
 FRI bulletin - Forest Research Institute, New Zealand Forest
 Service (160): p. 139-141; 1991.  Paper presented at the
 "FRI/NZFP Forest Ltd., Clonal Forestry Workshop, May 1-2,
 1989, Rotorua, New Zealand.
 
 Language:  English
 
 Descriptors: Forest trees; Clones; Hexazinone; Herbicide
 resistance; Genetic variation
 
 
 44                                NAL Call. No.: TP248.13.S68
 Cloning and expression of mutant EPSP-synthetase gene of
 Escherichia coli in transgenic plants.
 Mett, V.L.; Urmeeva, F.I.; Kobets, N.S.; Kolganova, T.V.;
 Aliev, K.A.; Piruzyan, E.S.
 New York, N.Y. : Allerton Press; 1991.
 Soviet biotechnology (3): p. 27-33; 1991.  Translated from:
 Biotekhnologiia, (3), 1991, p. 19-22, (TP248.2.B57).  Includes
 references.
 
 Language:  English; Russian
 
 Descriptors: Genetic engineering; Escherichia coli; Mutants;
 Glyphosate; Herbicide resistance; Treatment; Nitroso
 compounds; Guanidines; Genetic analysis; Phosphates; Ligases;
 Genetic code; Gene expression; Cloning; Plasmids; Transgenics;
 Nicotiana tabacum
 
 
 45                                    NAL Call. No.: 79.8 W41
 Cole crop (Brassica oleracea) tolerance to clomazone.
 Scott, J.E.; Weston, L.A.
 Champaign, Ill. : Weed Science Society of America; 1992 Jan.
 Weed science v. 40 (1): p. 7-11; 1992 Jan.  Includes
 references.
 
 Language:  English
 
 Descriptors: Brassica oleracea; Herbicide resistance;
 Clomazone; Bioassays; Chlorophyll; Biosynthesis; Application
 rates; Metabolic inhibitors; Mode of action; Metabolic
 detoxification; Source sink relations; Metabolites; Roots;
 Uptake; Translocation
 
 Abstract:  A laboratory bioassay was conducted to determine
 the differential tolerance of cole crops to clomazone as
 measured by extractable total chlorophyll and carotenoids.
 Clomazone concentrations causing 50% inhibition (I50) in the
 biosynthesis of total chlorophyll in broccoli, cauliflower,
 and green and red cabbage cotyledons were 16, 11, 3, and 11
 micromolar respectively, while I50 values for carotenoid
 levels were 20, 10, 4, and 8 micromolar clomazone,
 respectively. Therefore, broccoli was the most tolerant to
 clomazone based upon extractable chlorophyll and carotenoid
 concentrations. Further laboratory studies were performed to
 investigate the basis for differential clomazone tolerance in
 3-wk-old cole crop seedlings. No differences in total root
 uptake of 14C-clomazone were observed between these crops
 after 24 h. There were no differences in rate of metabolism of
 14C-clomazone to methanol-soluble metabolites in roots of
 these crops. Percentage of polar metabolites in roots remained
 fairly constant over time. There were also no differences
 between crops in percentage of methanol-soluble 14C-clomazone
 metabolites formed in shoots between 24 and 96 h. In all
 crops, levels of 14C-clomazone decreased in a similar manner
 over time in methanolic extracts of roots and shoots while
 nonextractable 14C levels increased, indicating a conversion
 of clomazone to insoluble, nonextractable forms. Differential
 uptake, translocation, and metabolism do not appear to account
 for clomazone selectivity differences between cole crop
 seedlings.
 
 
 46                                   NAL Call. No.: SB951.P49
 Comparative uptake, translocation, and metabolism of paraquat
 in tolerant Kwangkyo and susceptible Hood soybean.
 Kim, S.; Hatzios, K.K.
 Orlando, Fla. : Academic Press; 1993 Oct.
 Pesticide biochemistry and physiology v. 47 (2): p. 149-158;
 1993 Oct. Includes references.
 
 Language:  English
 
 Descriptors: Glycine max; Cultivars; Susceptibility; Herbicide
 resistance; Paraquat; Uptake; Deposition; Leaves; Waxes;
 Absorption; Spatial distribution; Plant tissues;
 Translocation; Metabolism; Mode of action
 
 Abstract:  The "Kwangkyo" and "Hood" cultivars of soybean
 [Glycine max (L.) Merr.] are differentially sensitive to the
 herbicide paraquat. The margin of this intraspecific
 differential herbicide tolerance is narrow and Kwangkyo is
 about 10-fold more tolerant to paraquat than Hood soybean. The
 deposition of epicuticular wax on the surface of the first
 fully expanded trifoliolate was similar in both soybean
 cultivars and treatment with 1 millimole paraquat did not
 influence the epicuticular wax content in any cultivar.
 Seedlings of Kwangkyo and Hood soybean absorbed comparable
 amounts of radioactivity following exposure to root-applied
 14C-labeled paraquat for 24 hr. Most of the absorbed
 radioactivity remained in the roots of seedlings of both
 cultivars, but a greater amount of the recovered radioactivity
 translocated from roots to stems and leaves of the sensitive
 Hood soybean. Following feeding of the cut ends of their
 petioles with [14C]paraquat for 12 and 24 hr, excised
 trifoliolates of Kwangkyo soybean retained a greater portion
 of absorbed radioactivity in their petioles and translocated a
 smaller amount of radioactivity into the interveinal regions.
 By contrast, excised trifoliolates of Hood soybean retained a
 smaller portion of absorbed radioactivity in their petioles
 and released a higher amount of absorbed radioactivity into
 the interveinal regions. Extractable paraquat was not
 metabolized to any extent by tissues of either of the two
 cultivars and differential metabolism does not appear to play
 a role in the observed differential response of Kwangkyo and
 Hood soybean to paraquat. Overall, the results of the present
 study suggest that restricted mobility or a delayed release of
 paraquat into the mesophyll region is a likely basis for the
 observed tolerance of Kwangkyo soybean to the herbicide
 paraquat.
 
 
 47                                   NAL Call. No.: SB610.W39
 Concerns a weed scientist might have about herbicide-tolerant
 crops. Radosevich, S.R.; Ghersa, C.M.; Comstock, G.
 Champaign, Ill. : The Society; 1992 Jul.
 Weed technology : a journal of the Weed Science Society of
 America v. 6 (3): p. 635-639; 1992 Jul.  Paper presented at
 the Symposium, "Development of Herbicide-Resistant Crop
 Cultivars", Weed Science Society of America, February 6, 1991,
 Louisville, Kentucky.  Includes references.
 
 Language:  English
 
 Descriptors: Transgenic plants; Crops; Herbicide resistance;
 Weed control; Biotechnology; Ethics
 
 
 48                                   NAL Call. No.: SB610.W39
 Concerns of seed company officials with herbicide-tolerant
 cultivars. Duvick, D.N.
 Champaign, Ill. : The Society; 1992 Jul.
 Weed technology : a journal of the Weed Science Society of
 America v. 6 (3): p. 640-646; 1992 Jul.  Paper presented at
 the Symposium, "Development of Herbicide-Resistant Crop
 Cultivars", Weed Science Society of America, February 6, 1991,
 Louisville, Kentucky.  Includes references.
 
 Language:  English
 
 Descriptors: Seed industry; Transgenic plants; Herbicide
 resistance; Cultivars; Biotechnology; Profitability; Supply
 balance; Research
 
 
 49                                    NAL Call. No.: QR53.B56
 Construction of multiple herbicide resistant ammonia excreting
 strains of cyanobacterium Nostoc muscorum.
 Modi, D.R.; Singh, D.R.; Rao, A.K.; Chakravarty, K.S.; Singh,
 H.N. Middlesex : Science and Technology Letters; 1991 Nov.
 Biotechnology letters v. 13 (11): p. 793-798; 1991 Nov. 
 Includes references.
 
 Language:  English
 
 Descriptors: Nostoc muscorum; Strains; Gloeocapsa; Herbicides;
 Herbicide resistance; Phenotypes; Dna; Genetic transformation;
 Gene transfer; Mutations; Ammonia; Excretion; Photosystem ii;
 Nitrogen fixation
 
 Abstract:  Machete resistant (Matr), basalin resistant (Basr),
 3(3,4 dichlorophenyl)-1,1-dimethyl urea resistant (DCMUr),
 atrazine resistant (Atr(r)) and propanil resistant (Prpr)
 phenotypes Gloeocapsa sp. were contransformed to Nostoc
 muscorum at high frequency. Spontaneously occurring mutants of
 the multiple herbicide resistant transformant containing L-
 methionine-DL-sulfoximine resistant (Msxr), ethylene diamine
 resistant (Edar) of phosphinothricin resistant (Pptr)
 glutamine synthetase (GS) showed extracellular liberation of
 ammonia resulting from fixation of N2 under photosynthetic
 conditions. Results suggest a definite role of GS activity in
 regulation of extracellular ammonia.
 
 
 50                                   NAL Call. No.: SB610.W39
 Control of annual bluegrass (Poa annua) in Kentucky bluegrass
 (Poa pratensis) turf with linuron.
 Hall, J.C.; Carey, C.K.
 Champaign, Ill. : The Weed Science Society of America; 1992
 Oct. Weed technology : a journal of the Weed Science Society
 of America v. 6 (4): p. 852-857; 1992 Oct.  Includes
 references.
 
 Language:  English
 
 Descriptors: Ontario; Cabt; Poa pratensis; Cultivars;
 Herbicide resistance; Linuron; Application rates; Poa annua;
 Weed control; Chemical control; Plant density; Quality;
 Seedling emergence; Injuries; Temperate climate
 
 
 51                                   NAL Call. No.: 79.9 W52R
 Control of diclofop-resistant Italian ryegrass.
 Brewster, B.D.; Donaldson, W.S.; Appleby, A.P.
 S.l. : The Society; 1992.
 Research progress report - Western Society of Weed Science. p.
 III/128; 1992. Meeting held on March 9-12, 1992, Salt Lake
 City, Utah.
 
 Language:  English
 
 Descriptors: Oregon; Lolium multiflorum; Diclofop; Herbicide
 resistance; Weed control
 
 
 52                                    NAL Call. No.: SB476.G7
 Controlling weeds in ornamental grasses.
 Whitwell, T.
 Overland Park, Kan. : Intertec Publishing Corporation; 1993
 Aug. Grounds maintenance v. 28 (8): p. 26-30; 1993 Aug.
 
 Language:  English
 
 Descriptors: Grasses; Ornamental herbaceous plants; Weed
 control; Herbicides; Herbicide resistance
 
 
 53                                   NAL Call. No.: SB951.P49
 Correlation of propanil hydrolyzing enzyme activity with leaf
 morphology in wild rices of genome CCDD.
 Jun, C.J.; Matsunaka, S.
 Orlando, Fla. : Academic Press; 1991 May.
 Pesticide biochemistry and physiology v. 40 (1): p. 80-85;
 1991 May.  Includes references.
 
 Language:  English
 
 Descriptors: Oryza; Wild plants; Hybrids; Leaves; Plant
 morphology; Amidase; Enzyme activity; Herbicide resistance;
 Propanil; Phytotoxicity
 
 Abstract:  The propanil hydrolyzing enzyme, aryl acylamidase I
 (AAI) (arylacylamine amidohydrolase, EC 3.5.1.13), was highly
 correlated (r = -0.83) with leaf width in three species of
 genus Oryza with genome CCDD. The specific activity of AAI was
 lower in the leaves of wide-leafed plants and this was well-
 reflected in propanil phytotoxicity in those plants. There
 were no significant differences between conjugation of 3,4-
 dichloroaniline or the presence of AAI inhibitors in the crude
 enzyme solutions from the narrow-leafed and wide-leafed
 strains. The same relationship between AAI activity and leaf
 width was observed in interspecific F, hybrids involving
 genome CCDD. In those F1 hybrids the wide- and narrow-leafed
 strains showed comparable AAI activity per leaf of equal
 length. It was concluded that the concentration of the enzyme
 in the CCDD plants was diluted by plant bulk in the wide-
 leafed strains and the correlation appeared to be the indirect
 effect of genes altering plant morphology, especially leaf
 area. The significance of the correlations is discussed in
 relation to propanil resistance and plant phylogenetics.
 
 
 54                                    NAL Call. No.: 442.8 Z8
 The cost of herbicide resistance measured by a competition
 experiment. Reboud, X.; Till-Bottraud, I.
 Berlin, W. Ger. : Springer International; 1991.
 Theoretical and applied genetics v. 82 (6): p. 690-696; 1991. 
 Includes references.
 
 Language:  English
 
 Descriptors: Setaria italica; Herbicide resistance; Atrazine;
 Plant competition; Shoots; Dry matter; Plant height; Seed set;
 Seeds; Line differences; Plant density
 
 Abstract:  The cost of resistance has been measured by a
 competition experiment over a ranee of densities, in the
 absence of herbicide treatment, on two nearly isogenic lines
 of Foxtail millet, differing in a chloroplastic resistance to
 herbicide. Three characters have been measured: shoot height,
 shoot weight, and seed production. Sensitive individuals were
 better competitors despite a larger decrease in production
 under within-biotype competition. The cost of resistance was
 density dependent and increased with density. The cost was
 higher when measured on seed production and reached 65% at the
 higher density for resistant individuals. This is compatible
 with the low frequency or the absence of that gene in natural
 populations. This work illustrates that the cost is easiest to
 observe when high levels of constraints are used.
 
 
 55                                 NAL Call. No.: SB113.2.S45
 Cotton meets the biotech challenge: genetic engineering races
 to the marketplace.
 Cutler, K.
 Cedar Falls, IA : Freiberg Pub. Co; 1991 Nov.
 Seed industry v. 42 (10): p. 4-5, 19; 1991 Nov.
 
 Language:  English
 
 Descriptors: Gossypium; Bromoxynil; Herbicide resistance;
 Genetic engineering; Field tests; Sulfonylurea herbicides;
 Usda
 
 
 56                                    NAL Call. No.: 450 P692
 Cross-resistance to herbicides in annual ryegrass (Lolium
 rigidum). II. Chlorsulfuron resistance involves a wheat-like
 detoxification system. Christopher, J.T.; Powles, S.B.;
 Liljegren, D.R.; Holtum, J.A.M. Rockville, Md. : American
 Society of Plant Physiologists; 1991 Apr. Plant physiology v.
 95 (4): p. 1036-1043; 1991 Apr.  Includes references.
 
 Language:  English
 
 Descriptors: Lolium rigidum; Triticum aestivum; Biotypes;
 Chlorsulfuron; Herbicide resistance; Cross resistance;
 Metabolism; Ligases; Translocation; Phytotoxicity; Metabolic
 detoxification; Biochemical pathways
 
 Abstract:  Lolium rigidum Gaud. biotype SLR31 is resistant to
 the herbicide diclofop-methyl and cross-resistant to several
 sulfonylurea herbicides. Wheat and the cross-resistant
 ryegrass exhibit similar patterns of resistance to
 sulfonylurea herbicides, suggesting that the mechanism of
 resistance may be similar. Cross-resistant ryegrass is also
 resistant to the wheat-selective imidazolinone herbicide
 imazamethabenz. The cross-resistant biotype SLR31 metabolized
 [phenyl-U-14C]chlorsulfuron at a faster rate than a biotype
 which is susceptible to both diclolop-methyl and
 chlorsulfuron. A third biotype which is resistant to diclofop-
 methyl but not to chlorsulfuron metabolized chlorsulfuron at
 the same rate as the susceptible biotype. The increased
 metabolism of chlorsulfuron observed in the cross-resistant
 biotype is, therefore, correlated with the patterns of
 resistance observed in these L. rigidum biotypes. During high
 performance liquid chromatography analysis the major
 metabolite of chlorsulfuron in both susceptible and cross-
 resistant ryegrass coeluted with the major metabolite produced
 in wheat. The major product is clearly different from the
 major product in the tolerant dicot species, flax (Linium
 usitatissimum). The elution pattern of metabolites of
 chlorsulfuron was the same for both the susceptible and cross-
 resistant ryegrass but the cross-resistant ryegrass
 metabolized chlorsulfuron more rapidly. The investigation of
 the dose response to sulfonylurea herbicides at the whole
 plant level and the study of the metabolism of chlorsulfuron
 provide two independent sets of data which both suggest that
 the resistance to chlorsulfuron in cross-resistant ryegrass
 biotype SLR31 involves a wheat-like detoxification system.
 
 
 57                                    NAL Call. No.: 450 P692
 Cross-resistance to herbicides in annual ryegrass (Lolium
 rigidum). III. On the mechanism of resistance to diclofop-
 methyl.
 Holtum, J.A.M.; Matthews, J.M.; Hausler, R.E.; Lijegren, D.R.;
 Powles, S.B. Rockville, Md. : American Society of Plant
 Physiologists; 1991 Nov. Plant physiology v. 97 (3): p.
 1026-1034; 1991 Nov.  Includes references.
 
 Language:  English
 
 Descriptors: Australia; Lolium rigidum; Leaves; Diclofop;
 Herbicide resistant weeds; Biotypes; Metabolism; Uptake;
 Translocation; Genetic variation; Weed control; Weed biology
 
 Abstract:  Annual ryegrass (Lolium rigidum) biotype SLR 31 is
 resistant to the postemergent graminicide methyl-2-[4-(2,4-
 dichlorophenoxy) phenoxy]-propanoate (diclofop-methyl). Uptake
 of [14C](Uphenyl)diclofop-methyl and root/shoot distribution
 of radioactivity in susceptible and resistant plants were
 similar. In both biotypes, diclofop-methyl was rapidly
 demethylated to the biocidal metabolite diclofop acid which,
 in turn, was metabolized to ester and aryl-O-sugar conjugates.
 Susceptible plants accumulated 5 to 15% more radioactivity in
 diclofop acid than did resistant plants. Resistant plants had
 a slightly greater capacity to form nonbiocidal sugar
 conjugates. Despite these differences, resistant plants
 retained 20% of 14C in the biocidal metabolite diclofop acid
 192 hours after treatment, whereas susceptible plants, which
 were close to death, retained 30% in diclofop acid. The small
 differences in the pool sizes of the active and inactive
 metabolites are by themselves unlikely to account for a 30-
 fold difference in sensitivity to the herbicide at the whole
 plant level. Similar highpressure liquid chromatography
 elution patterns of conjugates from both susceptible and
 resistant biotypes indicated that the mechanisms and the
 products of catabolism in the biotypes are similar. It is
 suggested that metabolism of diclofop-methyl by the resistant
 biotype does not alone explain resistance observed at the
 whole-plant level. Diclofop acid reduced the electrochemical
 potential of membranes in etiolated coleoptiles of both
 biotypes; 50% depolarization required 1 to 4 micromole
 diclofop acid. After removal of diclofop acid, membranes from
 the resistant biotype recovered polarity, whereas membranes
 from the susceptible biotype did not. Internal concentrations
 of diclofop acid 4 h after exposing plants to herbicide were
 estimated to be 36 to 39 micromolar in a membrane fraction and
 16 to 17 micromolar in a soluble fraction. Such concentrations
 should be sufficient to fully depolarize membranes.  It is
 postulated that differences in the ability of membranes to
 recover from depolarization are correlated with the resistance
 response of biotype SLR 31.
 
 
 58                                    NAL Call. No.: 450 P692
 Cross-resistance to herbicides in annual ryegrass (Lolium
 rigidum). IV. Correlation between membrane effects and
 resistance to graminicides. Hausler, R.E.; Holtum, J.A.M.;
 Powles, S.B.
 Rockville, Md. : American Society of Plant Physiologists; 1991
 Nov. Plant physiology v. 97 (3): p. 1035-1043; 1991 Nov. 
 Includes references.
 
 Language:  English
 
 Descriptors: Australia; Lolium rigidum; Biotypes; Herbicide
 resistant weeds; Weed control; Cross resistance; Diclofop;
 Fluazifop; Herbicides; Weed biology; Cell membranes; Polarity;
 Membrane potential
 
 Abstract:  The herbicidally active aryloxyphenoxypropionates
 diclofop acid, haloxyfop acid, and fluazifop acid and the
 cyclohexanedione sethoxydim depolarized membranes in
 coleoptiles of eight biotypes of herbicide-susceptible and
 herbicide-resistant annual ryegrass (Lolium rigidum). Membrane
 polarity was reduced from -100 millivolts to -30 to -50
 millivolts. Membranes repolarized after removal of the
 compounds only in biotypes with resistance to the compound
 added. Repolarization was not observed in herbicide-
 susceptible L. rigidum, nor was it observed in biotypes
 resistant to triazine, triazole, triazinone, phenylurea, or
 sulfonylurea herbicides but not resistant to
 aryloxyphenoxypropionates and cyclohexanediones.
 Chlorsulfuron, a sulfonylurea herbicide, at a saturating
 concentration of 1 micromolar, reduced membrane polarity in
 all biotypes studied by only 15 millivolts. The recovery of
 membrane potential following the removal of chlorsulfuron was
 restricted to chlorsulfuron-susceptible and -resistant
 biotypes that did not exhibit diclofop resistance. These
 differences in membrane responses are correlated with
 resistance to diclofop rather than with resistance to
 chlorsulfuron. It is suggested that the differences may
 reflect altered membrane properties of diclofop-resistant
 biotypes. Further circumstantial evidence for dissimilarity of
 properties of membranes from diclofop-resistant and diclofop-
 susceptible ryegrass is provided by observations that K+/Na+
 ratios were significantly higher in coleoptiles from diclofop-
 resistant biotypes than in coleoptiles from susceptible
 plants. Intact and excised roots from susceptible biotypes
 were capable of acidifying the external medium, whereas roots
 from resistant biotypes were unable to do so. The ineluctable
 conclusion is that in L. rigidum the phenomena of membrane
 repolarization and resistance to aryloxyphenoxypropionate and
 cyclohexanedione herbicides are correlated.
 
 
 59                                 NAL Call. No.: 442.8 B5236
 Dark adapted leaves of paraquat-resistant tobacco plants emit
 less ultraweak light than susceptible ones.
 Hideg, E.; Inaba, H.
 Orlando, Fla. : Academic Press; 1991 Jul31.
 Biochemical and biophysical research communications v. 178
 (2): p. 438-443; 1991 Jul31.  Includes references.
 
 Language:  English
 
 Descriptors: Nicotiana tabacum; Leaves; Paraquat; Herbicide
 resistance; Biotypes; Superoxide dismutase; Dark; Light;
 Emission; Light intensity
 
 Abstract:  Long term light emission was compared from leaves
 of paraquat-resistant and -susceptible tobacco plants. In the
 minutes time scale, delayed light emission of the two biotypes
 was similar both in kinetics and in intensity. However, after
 several hours in the dark, ultraweak light emission from
 leaves of resistant plants was about one third of the light
 emitted by susceptible samples, We suggest, that this
 difference is due to the higher activity of superoxide
 dismutase in resistant biotypes, earlier reported by Tanaka et
 al. (1988) (Plant Cell Physiol. 29, 743-746), and propose a
 model for the mechanism of ultraweak light emission from these
 samples.
 
 
 60                                   NAL Call. No.: SB951.P47
 Deamination of metribuzin in tolerant and susceptible soybean
 (Glycine max) cultivars.
 Fedtke, C.
 Essex : Elsevier Applied Science Publishers; 1991.
 Pesticide science v. 31 (2): p. 175-183; 1991.  Includes
 references.
 
 Language:  English
 
 Descriptors: Glycine max; Cultivars; Herbicide resistance;
 Susceptibility; Metribuzin; Carbon; Deamination; Isotope
 labeling; Metabolites; Herbicide residues
 
 Abstract:  The deamination of metribuzin was studied in vitro
 in peroxisomes isolated from the leaves of soybean cultivars
 which were either metribuzin tolerant, intermediate, or
 sensitive. The deamination rate observed with peroxisomes from
 tolerant leaves was about twice the rate observed with
 peroxisomes from sensitive leaves. The intermediate group was
 also intermediate with respect to the in-vitro deamination
 rate. Tolerant and sensitive intact soybean plants were pulse-
 labeled with [14C]metribuzin via the roots for 5 h. The
 extractable radioactivity in roots, stems and leaves was
 measured and separated into metabolites after the 5 h pulse
 and after an additional 24 h growth in water. The level of DA
 (deaminated metribuzin) was always significantly higher in the
 stems and leaves of tolerant soybean plants (4.8-10.0% of the
 extracted radioactivity) than in sensitive stems and leaves
 (1.8-2.9%). Conjugates were rapidly formed in tolerant as well
 as in sensitive soybean tissues. More conjugates were found in
 the tolerant cultivars, especially after the 5 + 24 h
 incubation time. Labeled [14C]DA fed to soybean plants via the
 roots was conjugated two to four times faster than
 [14C]metribuzin. Tolerant soybean tissue conjugated [14C]DA
 two to three times faster than sensitive tissue. The results
 are interpreted as showing that, in tolerant soybean plants,
 metribuzin is metabolized via deamination and subsequent
 conjugation, in addition to the well-known direct conjugation
 of metribuzin parent compound.
 
 
 61                                NAL Call. No.: SB950.2.I3I4
 Developing herbicide resistance in corn.
 Schoper, J.; Armstrong-Gustafson, P.; McBratney, B.
 Urbana, Ill. : Cooperative Extension Service, Univ of Illinois
 at Urbana-Champaign; 1991.
 Illinois Agricultural Pesticides Conference summaries of
 presentations January 8, 9, 10, 1991, Urbana, Illinois / Univ
 of Illinois at Urbana-Champaign, Coop Ext Serv, in coop with
 the Illinois Natural History Survey. p. 59-60; 1991.
 "Proceedings of the 1991 Illinois Agricultural Pesticides
 Conference," January 8-10, 1991, Urbana, Illinois.
 
 Language:  English
 
 Descriptors: Zea mays; Herbicide resistance
 
 
 62                             NAL Call. No.: TP248.27.P55P52
 Developing herbicide resistance in crops by gene transfer
 technology. Stalker, D.M.
 New York, N.Y. : Chapman and Hall; 1991.
 Plant biotechnology v. 1: p. 82-104; 1991.  In the series
 analytic: Plant genetic engineering / edited by D. Grierson. 
 Literature review.  Includes references.
 
 Language:  English
 
 Descriptors: Crops; Gene transfer; Herbicide resistance;
 Genetic transformation; Vectors; Plasmids; Transgenics;
 Agrobacterium tumefaciens; Agrobacterium rhizogenes; Direct 
 DNAuptake; Literature reviews
 
 
 63                                   NAL Call. No.: SB610.W39
 Developing herbicide-tolerant crop cultivars: introduction.
 Harrison, H.F. Jr
 Champaign, Ill. : The Society; 1992 Jul.
 Weed technology : a journal of the Weed Science Society of
 America v. 6 (3): p. 613-614; 1992 Jul.  Paper presented at
 the Symposium, "Development of Herbicide-Resistant Crop
 Cultivars", Weed Science Society of America, February 6, 1991,
 Louisville, Kentucky.  Includes references.
 
 Language:  English
 
 Descriptors: Transgenic plants; Crops; Herbicide resistance;
 Cultivars; Genotypes; Genetic engineering; Biotechnology
 
 
 64                                   NAL Call. No.: QH301.A76
 Development of herbicide tolerance in peas. I. Tissue culture
 and in vitro selection.
 Van Roggen, P.M.; Kirkwood, R.C.; Boyd, P.A.
 Wellesbourne, Warwick : The Association of Applied Biologists;
 1991. Aspects of applied biology (27): p. 267-270; 1991.  In
 the series analytic: Production and protection of legumes /
 edited by R.J. Froud-Williams, P. Gladders, M.C. Heath, J.F.
 Jenkyn, C.M. Knott, A. Lane and D. Pink.  Includes references.
 
 Language:  English
 
 Descriptors: Pisum sativum; Callus; Growth; Growth inhibitors;
 Herbicides; Resistance; Glyphosate; Metsulfuron; Tissue
 culture
 
 
 65                                   NAL Call. No.: QH301.A76
 Development of herbicide tolerance in peas. II. Regeneration
 via somatic embryogenesis.
 Van Doorne, L.E.; Marshall, G.; Kirkwood, R.C.
 Wellesbourne, Warwick : The Association of Applied Biologists;
 1991. Aspects of applied biology (27): p. 271-274; 1991.  In
 the series analytic: Production and protection of legumes /
 edited by R.J. Froud-Williams, P. Gladders, M.C. Heath, J.F.
 Jenkyn, C.M. Knott, A. Lane and D. Pink.  Includes references.
 
 Language:  English
 
 Descriptors: Pisum sativum; Cultivars; Culture media;
 Genotypes; Herbicide resistance; Diflufenican; Glyphosate;
 Metsulfuron; Somatic embryogenesis
 
 
 66                                   NAL Call. No.: QK600.M82
 Development of resistance in Bipolaris oryzae against
 edifenphos. Annamalai, P.; Lalithakumari, D.
 Cambridge : Cambridge University Press; 1992 Jun.
 Mycological research v. 96 (pt.6): p. 454-460; 1992 Jun. 
 Includes references.
 
 Language:  English
 
 Descriptors: Oryza sativa; Bipolaris; Plant pathogenic fungi;
 Edifenphos; Herbicide resistance; Mutants; Adaptation;
 Virulence; Pathogenicity; Strain differences
 
 
 67                                   NAL Call. No.: QH301.N32
 Development of shade-type appearance-light intensity
 adaptation and regulation of the D1 protein Synechococcus.
 Koenig, F.
 New York, N.Y. : Plenum Press; 1992.
 NATO ASI series : Series A : Life sciences v. 226: p. 545-550;
 1992.  In the series analytic: Regulation of chloroplast
 biogenesis / edited by J.H. Argyroudi-Akoyunoglou. Proceedings
 of a NATO Advanced Research Workshop, July 28-August 3, 1991,
 Crete, Greece.  Includes references.
 
 Language:  English
 
 Descriptors: Synechococcus; Biological development; Light
 intensity; Photosynthesis; Plant proteins; Protein synthesis;
 Shade; Herbicide resistance; Mutants
 
 
 68                                    NAL Call. No.: 442.8 Z8
 The development of sulfonylurea herbicide-resistant birdsfoot
 trefoil (Lotus corniculatus) plants from in vitro selection.
 Pofelis, S.; Le, H.; Grant, W.F.
 Berlin, W. Ger. : Springer International; 1992.
 Theoretical and applied genetics v. 83 (4): p. 480-488; 1992. 
 Includes references.
 
 Language:  English
 
 Descriptors: Lotus corniculatus; In vitro selection; Herbicide
 resistance; Sulfonylurea herbicides; Callus; Tissue culture;
 Shoots; Regeneration; Inheritance; Oxo-acid-lyases; Enzyme
 activity; Phytotoxicity
 
 Abstract:  Herbicide-resistant lines of birdsfoot trefoil
 (Lotus corniculatus L. cv 'Leo') were isolated after
 sequential selection at the callus, shoot, and whole plant
 levels to the sulfonylurea (SU) herbicide Harmony [DPX-M6316;
 3-[[[(4-methoxy-6methyl-1,3,5, triazine-2-yl) amino] carbonyl]
 amino] sulfonyl-2-thiophenecarboxylate]. In field and growth
 chamber tests the Harmony regenerant lines displayed an
 increased tolerance as compared to control plants from tissue
 culture and controls grown from seed. Results of evaluation of
 callus cultures of regenerated mutant lines signify stability
 of the resistance. Outcrossed seeds collected from field
 trials, and tested in vitro for herbicide resistance, indicate
 that the trait is heritable and that resistance may be due to
 reduced sensitivity of acetolactate synthase to SU inhibition.
 Genetically stable herbicide-resistant lines of birdsfoot
 trefoil were successfully isolated using in vitro selection.
 
 
 69                                   NAL Call. No.: 64.8 C883
 Development of sulfonylurea-resistant rapeseed using chemical
 mutagenesis. Tonnemaker, K.A.; Auld, D.L.; Thill, D.C.;
 Mallory-Smith, C.A.; Erickson, D.A. Madison, Wis. : Crop
 Science Society of America; 1992 Nov. Crop science v. 32 (6):
 p. 1387-1391; 1992 Nov.  Includes references.
 
 Language:  English
 
 Descriptors: Brassica napus; Herbicide resistance;
 Chlorsulfuron; Metsulfuron; Screening; Induced mutations;
 Sulfonylurea herbicides; Cultivars; Mutants; Varietal
 susceptibility; Genotypes
 
 Abstract:  Residual levels of sulfonylurea (SU) herbicides in
 the soil have limited rapeseed (Brassica napus L. var. napus)
 production in the Pacific Northwest. In a greenhouse screening
 procedure, the test herbicide suppressed the growth of
 susceptible rapeseed plants but allowed normal growth of
 resistant plants. Mutant (M2) populations of 'Cascade',
 'Bridger', and 'Cathy' winter rapeseed, 'R-500' spring
 rapeseed (B. rapa L. subsp. rapa), and 'Tilney' spring mustard
 (Sinapis alba L.; syn F. hirta Moench.) were screened with
 DPX-G8311, a 5:1 mixture of the SU herbicides chlorsulfuron
 (2-chloro-N-[[(4-methoxy-6-methyl-1,3,5-triazin-2-
 yl)amino]carbonyl] benzenesulfonamide) and metsulfuron
 [(methyl
 1-[[[[(4-methoxy-6-methyl-1,3,5-triazin-2-yl)-
 amino]carbonyl]amino] sulfonyl)benzoate]], applied
 preemergence at 7.5 g a.i. ha-1. Approximately 243 000 M2
 seedlings were screened and 178 were selected for additional
 tests. In progeny tests, several M3 and M4 families were
 identified that survived 6.5 g a.i. ha-1 DPX-G8311 applied
 preemergence but failed to survive the same rate of DPX-G8311
 applied postemergence. DPX-G8311 was applied preemergence at 0
 to 64 g a.i. ha-1, to one M3 and six M4 families to determine
 a dose X family response relationship. Calculated 50% growth
 reduction (GR(50)) values for both number of nodes produced
 and dry weight accumulation were up to 25 times greater for
 the selected M3 and M4 families than for the susceptible
 cultivar Cascade. Rapeseed lines resistant to soil residual
 levels of SU herbicides but susceptible to SU herbicide foliar
 applied would allow rapeseed to be planted after a small-grain
 cereal to which a SU herbicide had been applied.
 
 
 70                                    NAL Call. No.: 450 P692
 Developmental variability of photooxidative stress tolerance
 in paraquat-resistant Conyza.
 Amsellem, Z.; Jansen, M.A.K.; Driesenaar, A.R.J.; Gressel, J.
 Rockville, MD : American Society of Plant Physiologists, 1926-
 ; 1993 Dec. Plant physiology v. 103 (4): p. 1097-1106; 1993
 Dec.  Includes references.
 
 Language:  English
 
 Descriptors: Egypt; Cabt; Conyza bonariensis; Oxidants;
 Detoxification; Stress response; Regulation; Enzyme activity;
 Light; Temperature; Paraquat; Herbicide resistance; Weed
 biology; Growth stages; Enzymes; Photoinhibition
 
 Abstract:  Paraquat-resistant hairy fleabane (Conyza
 bonariensis L. Cronq.) has been extensively studied, with some
 contention. A single, dominant gene pleiotropically controls
 levels of oxidant-detoxifying enzymes and tolerance to many
 photooxidants, to photoinhibition, and possibly to other
 stresses. The weed forms a rosette on humid short days and
 flowers in dry long days and, thus, needs plasticity to
 photooxidant stresses. In a series of four experiments over 20
 months, the resistant and susceptible biotypes were cultured
 in constant 10-h low-light short days at 25 degrees C.
 Resistance was measured as recovery from paraquat. The
 concentration required to achieve 50% inhibition of the
 resistant biotype was about 30 times that of the susceptible
 one just after germination, increased to > 300 times that of
 the susceptibles at 10 weeks of growth, and then decreased to
 20-fold, remaining constant except for a brief increase while
 bolting. Resistance increased when plants were induced to
 flower by long days. The levels of plastid superoxide
 dismutase and of glutathione reductase were generally highest
 in resistant plants compared to those of the susceptibles at
 the times of highest paraquat resistance, but they were
 imperceptibly different from the susceptible type at the times
 of lower paraquat resistance. Photoinhibition tolerance
 measured as quantum yield of oxygen evolution at ambient
 temperatures was highest when the relative amounts of enzymes
 were highest in the resistant biotype. Resistance to
 photoinhibition was not detected by chlorophyll a
 fluorescence. Enzyme levels, photoinhibition tolerance, and
 paraquat resistance all increased during flowering in both
 biotypes. Imperceptibly small increases in enzyme levels would
 be needed for 20-fold resistance, based on the moderate enzyme
 increases correlated with 300-fold resistance. Thus, it is
 feasible that either these enzymes play a role in the first
 line of defense against photooxidants, or another, yet unknown
 mechanism(s) facilitate(s) the lower level of resistance, or
 the enzymes and unknown mechanisms act together.
 
 
 71                                   NAL Call. No.: SB951.P49
 Diclofop and fenoxaprop resistance in wild oats is associated
 with an altered effect on the plasma membrane electrogenic
 potential.
 Devine, M.D.; Hall, J.C.; Romano, M.L.; Marles, M.A.S.;
 Thomson, L.W.; Shimabukuro, R.H.
 Orlando, Fla. : Academic Press; 1993 Mar.
 Pesticide biochemistry and physiology v. 45 (3): p. 167-177;
 1993 Mar. Includes references.
 
 Language:  English
 
 Descriptors: Manitoba; Avena fatua; Varietal susceptibility;
 Diclofop; Fenoxaprop; Insecticide resistance; Resistance
 mechanisms; Plasma membranes; Acetyl-coa carboxylase;
 Inhibition; Membrane potential; Electrical activity; Wild
 plants
 
 Abstract:  We have examined the mechanism of herbicide
 resistance in a biotype of wild oat (Avena fatua L.) that is
 resistant to diclofop-methyl and many other acetyl-coenzyme A
 carboxylase (ACCase) inhibitors. Resistance to diclofop-methyl
 and fenoxaprop-ethyl was not based on reduced uptake nor on
 enhanced metabolism of the herbicides to inactive products. In
 in vitro assays of crude or partially purified preparations,
 ACCase from the resistant (UM-1) and susceptible (UM-5)
 biotypes was equally sensitive to diclofop, with I50 values of
 6.1 and 7.3 micromolar for UM-1 and UM-5, respectively.
 Corresponding values for fenoxaprop were 2.5 and 1.0
 micromolar. These results suggest that the high level of
 resistance observed toward these herbicides is not based on an
 altered target enzyme. Root tissue from both UM-1 and UM-5
 acidified an unbuffered bathing solution. Addition of 100 KM
 diclofop or fenoxaprop prevented acidification of the bathing
 medium by UM-1, but alkalinization occurred rapidly with UM-5.
 When diclofop was removed from the treatment solution, UM-1
 resumed acidification of the solution, whereas the pH of the
 UM-5 bathing solution continued to increase. Diclofop (50
 micromolar) rapidly depolarized the cell membrane in peeled
 coleoptile sections, with no difference between UM-1 and UM-5.
 However, when diclofop was removed from the treatment
 solution, the electrogenic membrane potential was quickly
 reestablished in UM-1, but remained collapsed in UM-5. These
 results provide support for the hypothesis that the effect of
 diclofop on the plasma membrane potential is an important
 component of its herbicidal activity. The reversibility of the
 effect of diclofop and fenoxaprop on transmembrane proton flux
 in UM-1 appears to be associated with resistance to these
 herbicides.
 
 
 72                                   NAL Call. No.: SB610.W39
 Differential bentazon response in cowpea (Vigna unguiculata).
 Harrison, H.F. Jr; Fery, R.L.
 Champaign, Ill. : The Weed Science Society of America; 1993
 Jul. Weed technology : a journal of the Weed Science Society
 of America v. 7 (3): p. 756-758; 1993 Jul.  Includes
 references.
 
 Language:  English
 
 Descriptors: Vigna unguiculata; Cultivars; Germplasm;
 Screening; Herbicide resistance; Bentazone; Tolerance;
 Phytotoxicity; Varietal susceptibility; Crop damage; Abiotic
 injuries; Application
 
 
 73                                   NAL Call. No.: SB610.W39
 Differential competitiveness of sulfonylurea resistant and
 susceptible prickly lettuce (Lactuca serriola).
 Alcocer-Ruthling, M.; Thill, D.C.; Shafii, B.
 Champaign, Ill. : The Society; 1992 Apr.
 Weed technology : a journal of the Weed Science Society of
 America v. 6 (2): p. 303-309; 1992 Apr.  Includes references.
 
 Language:  English
 
 Descriptors: Idaho; Triticum aestivum; Crop weed competition;
 Lactuca serriola; Herbicide resistant weeds; Sulfonylurea
 herbicides; Biotypes; Growth rate; Competitive ability
 
 
 74                                    NAL Call. No.: 23 AU792
 Differential tolerance of annual medics, Nungarin subterranean
 clover and hedge mustard to broadleaf herbicides.
 Young, R.R.; Morthorpe, K.J.; Croft, P.H.; Nicol, H.
 East Melbourne : Commonwealth Scientific and Industrial
 Research Organization; 1992.
 Australian journal of experimental agriculture v. 32 (1): p.
 49-57; 1992. Includes references.
 
 Language:  English
 
 Descriptors: New South Wales; Medicago; Trifolium
 subterraneum; Crop damage; Herbicide resistance;
 Phytotoxicity; Sisymbrium; Weed control; 2,4-db; Bromoxynil;
 Diuron; Mcpa; Terbutryn
 
 
 75                                   NAL Call. No.: SB610.W39
 Differential tolerance of sweet potato (Ipomoea batatas)
 clones to metribuzin. Motsenbocker, C.E.; Monaco, T.J.
 Champaign, Ill. : The Weed Science Society of America; 1993
 Apr. Weed technology : a journal of the Weed Science Society
 of America v. 7 (2): p. 349-354; 1993 Apr.  Includes
 references.
 
 Language:  English
 
 Descriptors: North Carolina; Cabt; Ipomoea batatas;
 Metribuzin; Herbicide resistance; Phytotoxicity; Clones;
 Cultivars; Varietal susceptibility; Crop damage; Crop yield;
 Yield losses; Application date; Timing; Application rates;
 Genetic variation
 
 
 76                                   NAL Call. No.: SB610.W39
 Differential toxicity of tralkoxydim in Hordeum species.
 Tal, A.; Benyamini, Y.; Rubin, B.
 Champaign, Ill. : The Weed Science Society of America; 1993
 Oct. Weed technology : a journal of the Weed Science Society
 of America v. 7 (4): p. 946-948; 1993 Oct.  Includes
 references.
 
 Language:  English
 
 Descriptors: Hordeum vulgare; Hordeum glaucum; Hordeum
 spontaneum; Triticum aestivum; Phytotoxicity; Crop damage;
 Abiotic injuries; Tralkoxydim; Application rates; Selectivity;
 Wild plants; Species differences; Herbicide resistance
 
 
 77                                   NAL Call. No.: SB951.P49
 Direct demonstration of binding-site competition between
 photosystem II inhibitors at the QB niche of the D1 protein.
 Jansen, M.A.K.; Mattoo, A.K.; Malkin, S.; Edelman, M.
 Orlando, Fla. : Academic Press; 1993 May.
 Pesticide biochemistry and physiology v. 46 (1): p. 78-83;
 1993 May.  Includes references.
 
 Language:  English
 
 Descriptors: Photosystem ii; Membranes; Proteins; Binding
 site; Electron transfer; Diuron; Inhibitors; Protein
 degradation; Inhibition; Solanum nigrum; Spirodela oligorhiza;
 Biotypes; Herbicide resistance
 
 Abstract:  Inhibitors of photosystem II function have been
 shown to block electron flow in vitro by competitively
 displacing plastoquinone from the Q(B) niche on the D1
 protein. Few studies have tested this well-accepted concept in
 vivo and none in higher plants. The D1 protein degradation
 assay was used to directly demonstrate, in vivo, the
 displacement of diuron by bromonitrothymol (BNT) at the level
 of the Q(B) niche. We show that diuron blocks D1 degradation
 less effectively in the presence of BNT, and that this effect
 of BNT can be nullified by increasing the diuron
 concentration. These data directly demonstrate binding-site
 competition at the level of the Q(B) niche, under the complex
 physiological conditions of the intact higher plant.
 
 
 78                                    NAL Call. No.: 79.8 W41
 Distribution and characteristics of triazine-resistant powell
 amaranth (Amaranthus powellii) in Idaho.
 Eberlein, C.V.; Al-Khatib, K.; Guttieri, M.J.; Fuerst, E.P.
 Champaign, Ill. : Weed Science Society of America; 1992.
 Weed science v. 40 (4): p. 507-512; 1992.  Includes
 references.
 
 Language:  English
 
 Descriptors: Idaho; Amaranthus powellii; Herbicide resistance;
 Atrazine; Metribuzin; Diuron; Binding site; Thylakoids;
 Resistance mechanisms; Genetic analysis; Chloroplast genetics;
 Genes; Mutations; Nucleotide sequences; Amino acid sequences;
 Biotypes; Geographical distribution
 
 Abstract:  A triazine-resistant (TR) biotype of Powell
 amaranth was discovered in 1989 in a potato field treated with
 metribuzin. A survey of all agricultural counties in Idaho
 showed that the TR Powell amaranth infestation was localized
 in the southeastern corner of Gooding county in southern
 Idaho. To determine the mechanism of triazine resistance, I50
 values for inhibition of photosystem II were determined for
 atrazine, metribuzin, and diuron using thylakoids isolated
 from TR and triazine-susceptible (TS) biotypes. TR/TS ratios
 based on I50 values were 134 for atrazine, 62 for metribuzin,
 and 1.9 for diuron. Results of binding studies with atrazine
 and metribuzin were consistent with the I50 studies,
 indicating that resistance was due to reduced binding of
 triazines to the thylakoid membrane D1 protein. Sequencing the
 chloroplast psbA gene from TR and TS biotypes revealed a
 serine 264 to glycine change in the TR biotype. The mutation
 presumably resulted in reduced hydrogen bonding between
 triazine herbicides and the D1 protein.
 
 
 79                                    NAL Call. No.: 79.8 W41
 DNA sequence variation in domain A of the acetolactate
 synthase genes of herbicide-resistant and -susceptible weed
 biotypes.
 Guttieri, M.J.; Eberlein, C.V.; Mallory-Smith, C.A.; Thill,
 D.C.; Hoffman, D.L.
 Champaign, Ill. : Weed Science Society of America; 1992.
 Weed science v. 40 (4): p. 670-676; 1992.  Includes
 references.
 
 Language:  English
 
 Descriptors: Kochia scoparia; Lactuca serriola; Salsola
 iberica; Herbicide resistant weeds; Biotypes; Chlorsulfuron;
 Herbicide resistance; Genes; Nucleotide sequences; Amino acid
 sequences; Genetic variation; Weed biology
 
 Abstract:  The DNA sequence of a 196 base pair (bp) region of
 the acetolactate synthase (ALS) genes of three weed species,
 kochia, prickly lettuce, and Russian thistle was determined.
 This region encompasses the coding sequence for Domain A, a
 region of the amino acid sequence previously demonstrated to
 play a pivotal role in conferring resistance to herbicides
 that inhibit ALS. The Domain A DNA sequence from a
 chlorsulfuron-resistant (R) prickly lettuce biotype from Idaho
 differed from that of a chlorsulfuron-susceptible (S) biotype
 by a single point mutation, which substituted a histidine for
 a proline. The Domain A DNA sequence from an R kochia biotype
 from Kansas also differed from that of an S biotype by a
 single point mutation in the same proline codon. This point
 mutation, however, conferred substitution of threonine for
 proline. Two different ALS-homologous sequences were isolated
 from an R biotype of Russian thistle. Neither sequence encoded
 amino acid substitutions in Domain A that differed from the
 consensus S sequence. The DNA sequence variation among the R
 and S kochia biotypes was used to characterize six Ada County,
 Idaho, kochia collections for correlation between phenotypic
 chlorsulfuron susceptibility and restriction digest patterns
 (RFLPs) of polymerase chain reaction amplification products.
 Most collections showed excellent correspondence between the
 RFLP patterns and the phenotypic response to chlorsulfuron
 application. However, one entirely R collection had the RFLP
 pattern of the S biotype, suggesting that resistance was not
 due to mutation in the proline codon.
 
 
 80                                    NAL Call. No.: SB249.N6
 Documentation of graminicide-resistant johnsongrass in cotton.
 Snipes, C.E.; Barrentine, W.L.; Smeda, R.J.
 Memphis, Tenn. : National Cotton Council of America, 1991-;
 1993. Proceedings / v. 3: p. 1508; 1993.  Meeting held January
 10-14, 1993, New Orleans, Louisiana.
 
 Language:  English
 
 Descriptors: Sorghum halepense; Gossypium; Herbicide
 resistance
 
 
 81                                     NAL Call. No.: 472 N21
 Ecology of transgenic oilseed rape in natural habitats.
 Crawley, M.J.; Hails, R.S.; Rees, M.; Kohn, D.; Buxton, J.
 London : Macmillan Magazines Ltd; 1993 Jun.
 Nature v. 363 (6430): p. 620-623; 1993 Jun.  Includes
 references.
 
 Language:  English
 
 Descriptors: Brassica napus var. oleifera; Transgenics;
 Genetic engineering; Ecology
 
 Abstract:  Concerns about genetically engineered crop plants
 centre on three conjectural risks: that transgenic crop plants
 will become weeds of agriculture or invasive of natural
 habitats; that their engineered genes will be transferred by
 pollen to wild relatives whose hybrid offspring will then
 become more weedy or more invasive; or that the engineered
 plants will be a direct hazard to humans, domestic animals or
 beneficial wild organisms (toxic or allergenic, for example).
 Here we describe an experimental protocol for assessing the
 invasiveness of plants. The object is to determine whether
 genetic engineering for herbicide tolerance affects the
 likelihood of oilseed rape becoming invasive of natural
 habitats. By estimating the demographic parameters of
 transgenic and conventional oilseed rape growing in a variety
 of habitats and under a range of climatic conditions, we
 obtain a direct comparison of the ecological performance of
 three different genetic lines (control, kanamycin-tolerant
 transgenics and herbicide-tolerant transgenic lines). Despite
 substantial variation in seed survival, plant growth and seed
 production between sites and across experimental treatments,
 there was no indication that genetic engineering for kanamycin
 tolerance or herbicide tolerance increased the invasive
 potential of oilseed rape. In those cases in which there were
 significant differences (such as seed survival on burial),
 transgenic lines were less invasive and less persistent than
 their conventional counterparts.
 
 
 82                                   NAL Call. No.: 56.8 J822
 Economic and environmental implications of herbicide-tolerant
 corn and processing tomatoes.
 Hayenga, M.; Thompson, L.C.; Chase, C.; Kaaria, S.
 Ankeny, Iowa : Soil and Water Conservation Society of America;
 1992 Sep. Journal of soil and water conservation v. 47 (5): p.
 411-417; 1992 Sep. Includes references.
 
 Language:  English
 
 Descriptors: Zea mays; Lycopersicon esculentum; Hybrid
 varieties; Herbicide resistance; Crop production; Economic
 impact; Production costs; Environmental impact; Weed control
 
 
 83                                     NAL Call. No.: 450 C16
 Effect of diclofop and HOE-6001 on amylolytic enzyme
 activities of malt. McMullan, P.M.; Noll, J.; Therrien, M.C.
 Ottawa : Agricultural Institute of Canada; 1992 Apr.
 Canadian journal of plant science; Revue canadienne de
 phytotechnie v. 72 (2): p. 435-438; 1992 Apr.  Includes
 references.
 
 Language:  English
 
 Descriptors: Manitoba; Hordeum vulgare; Genotypes; Alpha-
 amylase; Alpha-glucosidase; Diclofop; Fenoxaprop; Herbicide
 resistance; Avena fatua; Setaria viridis; Weed control
 
 
 84                                    NAL Call. No.: 450 P692
 Effect of diclofop on the membrane potentials of herbicide-
 resistant and -susceptible annual ryegrass root tips.
 Shimabukuro, R.H.; Hoffer, B.L.
 Rockville, Md. : American Society of Plant Physiologists; 1992
 Apr. Plant physiology v. 98 (4): p. 1415-1422; 1992 Apr. 
 Includes references.
 
 Language:  English
 
 Descriptors: Australia; Lolium rigidum; Root tips;
 Plasmalemma; Membrane potential; Diclofop; Herbicide
 resistance; Susceptibility; Phytotoxicity
 
 Abstract:  Electrophysiological measurements were made on root
 tip cells in the elongation zone of diclofop-methyl-resistant
 (SR4/84) and -susceptible (SRS2) biotypes of annual ryegrass
 (Lolium rigidum Gaud.) from Australia. The phytotoxic action
 of diclofop-methyl (methyl
 2-[4-(2',4'-dichlorophenoxy)phenoxy]propanoate) on susceptible
 whole plants was completely reversed by a simultaneous
 application of
 2,4-dichlorophenoxyacetic acid (dimethylamine salt). The
 phytotoxic acid metabolite, diclofop (50 micromolar),
 depolarized membrane potentials of both biotypes to a steady-
 state level within 10 to 15 minutes. Repolarization of the
 membrane potential occurred only in the resistant biotype
 following removal of diclofop. The resistant biotype has an
 intrinsic ability to reestablish the electrogenic membrane
 potential, whereas the susceptible biotype required an
 exogeneous source of IAA to induce partial repolarization.
 Both biotypes were susceptible to depolarization by
 carbonylcyanide-m-chlorophenylhydrazone (CCCP), and their
 membrane potentials recovered upon removal of CCCP. A 15-
 minute pretreatment with p-chloromercuribenzenesulphonic acid
 (PCMBS) blocked the depolarizing action of diclofop in both
 biotypes. However, PCMBS had no effect on the activity of
 CCCP. The action of diclofop appears to involve a site-
 specific interaction at the plasmalemma in both Lolium
 biotypes to cause the increased influx of protons into
 sensitive cells. The differential response of membrane
 depolarization and repolarization to diclofop treatment may be
 a significant initial reaction in the eventual phytotoxic
 action of the herbicide.
 
 
 85                                   NAL Call. No.: SB610.W39
 Effect of ethalfluralin and other herbicides on trifluralin-
 resistant green foxtail (Setaria viridis).
 Beckie, H.J.; Morrison, I.N.
 Champaign, Ill. : The Weed Science Society of America; 1993
 Jan. Weed technology : a journal of the Weed Science Society
 of America v. 7 (1): p. 6-14; 1993 Jan.  Includes references.
 
 Language:  English
 
 Descriptors: Manitoba; Cabt; Setaria viridis; Herbicide
 resistant weeds; Trifluralin; Herbicide resistance; Biotypes;
 Weed control; Chemical control; Ethalfluralin; Dinitroaniline
 herbicides; Oryzalin; Isopropalin; Pendimethalin; Prodiamine;
 Propyzamide; Pyridine herbicides; Mitosis; Metabolic
 inhibitors; Propanil; Diclofop; Fenoxaprop; Fluazifop;
 Dalapon; Sethoxydim; Linuron; Eptc; Cross resistance;
 Phytotoxicity; Triticum aestivum; Brassica napus
 
 
 86                                    NAL Call. No.: 79.8 W41
 Effect of field violet (Viola arvensis) growth stage on
 uptake, translocation, and metabolism of terbacil.
 Doohan, D.J.; Monaco, T.J.; Sheets, T.J.
 Champaign, Ill. : Weed Science Society of America; 1992 Apr.
 Weed science v. 40 (2): p. 180-183; 1992 Apr.  Includes
 references.
 
 Language:  English
 
 Descriptors: Viola arvensis; Seedling stage; Maturity stage;
 Terbacil; Absorption; Translocation; Metabolic detoxification;
 Metabolism; Herbicide resistant weeds; Metabolites; Herbicide
 resistance; Variation
 
 Abstract:  Uptake, translocation, and metabolism of 14C-
 terbacil was investigated in 12-leaf (tolerant) and 3-leaf
 (susceptible) field violet plants. Field violets with 12
 leaves absorbed less 14C-terbacil g-1 of fresh weight from
 solution culture than did plants with three leaves. Plants
 with three leaves translocated twice as much radioactivity to
 foliage than did plants with 12 leaves. Most 14C in roots
 (77%) and foliage (57%) of field violet plants with 12 leaves
 was in polar metabolites. Metabolism studies indicated that
 most 14C (79%) in foliage extracts from field violet plants
 with three leaves was 14C-terbacil. Polar metabolites were not
 detected in roots of field violet plants with three leaves.
 
 
 87                                    NAL Call. No.: 450 P693
 Effect of four classes of herbicides on growth and
 acetolactate-synthase activity in several variants of
 Arabidopsis thaliana.
 Mourad, G.; King, J.
 Berlin : Springer-Verlag; 1992.
 Planta v. 188 (4): p. 491-497; 1992.  Includes references.
 
 Language:  English
 
 Descriptors: Arabidopsis thaliana; Ligases; Enzyme activity;
 Inhibition; Chlorsulfuron; Sulfonamides; Imazapyr; Benzoic
 acid herbicides; Mutants; Mutations; Loci; Alleles; Herbicide
 resistance; Binding site; Cross resistance
 
 Abstract:  We have isolated a triazolopyrimidine-resistant
 mutant csr1-2, of Arabidopsis thaliana (L.) Heynh. Here, we
 compare csr1-2 with the previously isolated mutants csr1 and
 csr1-1, and with wild-type Arabidopsis for responses to
 members of four classes of herbicides, namely, sulfonylureas,
 triazolopyrimidines, imidazolinones, and pyrimidyl-oxy-
 benzoates. Two separable herbicide-binding sites have been
 identified previously on the protein of acetolactate synthase
 (ALS). Here, the mutation giving rise to csr1, originating in
 a coding sequence towards the 5' end of the ALS gene, and that
 in csr1-2, affected the inhibitory action on growth and ALS
 activity of sulfonylurea and triazolopyrimidine herbicides but
 not that of the imidazolinones or pyrimidyl-oxybenzoates. The
 other mutation, in csr1-1, originating in a coding sequence
 towards the 3' end of the ALS gene, affected the inhibitory
 action of imidazolinones and pyrimidyl-oxy-benzoates but not
 that of the sulfonylureas or triazolopyrimidines. Additional,
 stimulatory effects of some of these herbicides on growth of
 seedlings was unrelated to their effect on their primary
 target, ALS. The conclusion from these observations is that
 one of the two previously identified herbicide-binding sites
 may bind sulfonylureas and triazolopyrimidines while the other
 may bind imidazolinones and pyrimidyl-oxybenzoates within a
 herbicide-binding domain on the ALS enzyme. Such a comparative
 study using near-isogenic mutants from the same species allows
 not only the further definition of the domain of herbicide
 binding on ALS but also could aid investigation of the
 relationship between herbicide-, substrate-, and allosteric-
 binding sites on this enzyme.
 
 
 88                                  NAL Call. No.: 511 P444AE
 Effect of treating plants with abscisic acid on its
 concentration in leaves and resistance of three pea cultivars
 to the herbicide 2,4-D. Melekhov, E.I.; Lavrent'ev, A.A.
 New York, N.Y. : Consultants Bureau; 1992.
 Doklady : botanical sciences - Akademiia nauk SSSR v. 319/321:
 p. 79-82; 1992.  Translated from: Akademiia Nauk SSSR.
 Doklady. v. 319/321, 1991, p. 1273-1277, (511 P444A). 
 Includes references.
 
 Language:  English; Russian
 
 Descriptors: Pisum sativum; Cultivars; Herbicide resistance;
 2,4-d; Plants; Treatment; Abscisic acid; Growth chambers;
 Survival
 
 
 89                                   NAL Call. No.: SB610.W39
 Effective kill of trifluralin-susceptible and -susceptible
 agreen foxtail (Setaria viridis).
 Beckie, H.J.; Morrison, I.N.
 Champaign, Ill. : The Weed Science Society of America; 1993
 Jan. Weed technology : a journal of the Weed Science Society
 of America v. 7 (1): p. 15-22; 1993 Jan.  Includes references.
 
 Language:  English
 
 Descriptors: Manitoba; Cabt; Triticum aestivum; Brassica
 napus; Weed control; Setaria viridis; Herbicide resistant
 weeds; Trifluralin; Herbicide resistance; Biotypes;
 Application rates; Chemical control; Application methods;
 Phytotoxicity; Susceptibility
 
 
 90                                   NAL Call. No.: 450 J8224
 Effects of 4-chloro-2-methylphenoxypropionate (an auxin
 analogue) on plasma membrane ATPase activity in herbicide-
 resistant and herbicide-susceptible biotypes of Stellaria
 media L.
 Coupland, D.; Cooke, D.T.; James, C.S.
 Oxford : Oxford University Press; 1991 Aug.
 Journal of experimental botany v. 42 (241): p. 1065-1071; 1991
 Aug.  Includes references.
 
 Language:  English
 
 Descriptors: Stellaria media; Mecoprop; Herbicide resistant
 weeds; Herbicide resistance; Adenosinetriphosphatase; Enzyme
 activity; Plasma membranes; Atp; Hydrolysis; Biotypes; Proton
 pump; Phospholipids; Sterols
 
 Abstract:  ATPase activity was examined in plasma membrane
 (PM) fractions prepared from mecoprop-resistant and -
 susceptible biotypes of Stellaria media L. (chickweed).
 Treatment with the herbicide caused an 18% increase in ATP
 hydrolysis, but this was not significantly different from
 control plants and was similar for both biotypes. However,
 there was an overall significant biotype effect, herbicide-
 resistant plants having greater enzyme activity than
 susceptible ones. Proton-pumping was readily demonstrated in
 PM fractions obtained from both biotypes using the fluorescent
 probe
 amino-chloro-methoxyacridine (ACMA), indicating a relatively
 large proportion of 'inside-out' vesicles. Proton-pumping was
 significantly greater in PM preparations obtained from the
 resistant compared with susceptible plants. The differences in
 ATPase activity between the two biotypes could not be
 attributed to differences in the main sterol or phospholipid
 components of the PM. There were no effects of the herbicide
 on ATP hydrolysis in vitro, but proton-pumping was affected in
 a herbicide concentration-dependent manner. At 1.0 mol m-6
 mecoprop caused an increase in the rate of proton-pumping,
 whereas at 10 and 100 mol m-6, an inhibition in this rate was
 observed. Both biotypes behaved similarly, irrespective of
 mecoprop concentration. These data indicate that mecoprop
 resistance in chickweed is unlikely to be due to a direct
 effect of the herbicide on PM H+ -ATPase activity.
 
 
 91                                    NAL Call. No.: 450 P692
 Effects of acetyl-coenzyme A carboxylase inhibitors on root
 cell transmembrane electric potentials in graminicide-tolerant
 and -susceptible corn (Zea mays L.).
 Dotray, P.A.; DiTomaso, J.M.; Gronwald, J.W.; Wyse, D.L.;
 Kochian, L.V. Rockville, MD : American Society of Plant
 Physiologists, 1926-; 1993 Nov. Plant physiology v. 103 (3):
 p. 919-924; 1993 Nov.  Includes references.
 
 Language:  English
 
 Descriptors: Zea mays; Lines; Herbicides; Tolerance;
 Susceptibility; Membrane potential; Soil ph
 
 Abstract:  Herbicidal activity of aryloxyphenoxypropionate and
 cyclohexanedione herbicides (graminicides) has been proposed
 to involve two mechanisms: inhibition of acetyl-coenzyme A
 carboxylase (ACCase) and depolarization of cell membrane
 potential. We examined the effect of aryloxyphenoxypropionates
 (diclofop and haloxyfop) and cyclohexanediones (sethoxydim and
 clethodim) on root cortical cell membrane potential of
 graminicide-susceptible and -tolerant corn (Zea mays L.)
 lines. The graminicide-tolerant corn line contained a
 herbicide-insensitive form of ACCase. The effect of the
 herbicides on membrane potential was similar in both corn
 lines. At a concentration of 50micromolar, the
 cyclohexanediones had little or no effect on the membrane
 potential of root cells. At pH 6, 50 micromolar diclofop, but
 not haloxyfop, depolarized membrane potential, whereas both
 herbicides (50 micromolar) dramatically depolarized membrane
 potential at pH 5. Repolarization of membrane potential after
 removal of haloxyfop and diclofop from the treatment solution
 was incomplete at pH 5. However, at pH 6 nearly complete
 repolarization of membrane potential occurred after removal of
 diclofop. In graminicide-susceptible corn, root growth was
 significantly inhibited by a 24-h exposure to 1 micromolar
 haloxyfop or sethoxydim, but cell membrane potential was
 unaffected. In gramincide-tolerant corn, sethoxydim treatment
 (1 micromolar, 48 h) had no effect on root growth, whereas
 haloxyfop (1 micromolar, 48 h) inhibited root growth by 78%.
 However, membrane potential was the same in roots treated with
 1 micromolar haloxyfop or sethoxydim. The results of this
 study indicate that graminicide tolerance in the corn line
 used in this investigation is not related to an altered
 response at the cell membrane level as has been demonstrated
 with other resistant species.
 
 
 92                                   NAL Call. No.: SB951.P49
 Effects of isoxaben on sensitive ant tolerant plant cell
 cultures. I. Metabolic fate of isoxaben.
 Corio-Costet, M.F.; Dall'Agnese, M.; Scalla, R.
 Orlando, Fla. : Academic Press; 1991 Jul.
 Pesticide biochemistry and physiology v. 40 (3): p. 246-254;
 1991 Jul. Includes references.
 
 Language:  English
 
 Descriptors: Triticum aestivum; Glycine max; Cell suspensions;
 Cell cultures; Isoxaben; Phytotoxicity; Herbicide resistance;
 Susceptibility; Line differences; Metabolic detoxification;
 Metabolites
 
 Abstract:  A soybean cell line tolerance to isoxaben was
 isolated by callus selection in herbicide-containing medium.
 The growth of tolerant suspension cells was not affected by 10
 micromoles isoxaben, which prevented the growth of wild-type
 cultures. The growth of a wheat cell culture was little
 affected by isoxaben, in accordance to the tolerance of wheat
 plants to the herbicide. The metabolic fate of labeled
 isoxaben in the three types of cultures was examined. By
 comparison with the sensitive, wild-type soybean cell culture,
 the tolerance of the selected soybean cell culture and that of
 wheat cell culture cannot be explained by either quantitative
 or qualitative differences of herbicide metabolism. These
 results favor the hypothesis that the sensitivity or tolerance
 of the cell cultures is determined at the level of the
 cellular target of the herbicide.
 
 
 93                                   NAL Call. No.: SB951.P49
 Effects of isoxaben on senstitive and tolerant plant cell
 cultures. II. Cellular alterations and inhibition on the
 synthesis of acid-insoluble cell wall material.
 Corio-Costet, M.F.; Lherminier, J.; Scalla, R.
 Orlando, Fla. : Academic Press; 1991 Jul.
 Pesticide biochemistry and physiology v. 40 (3): p. 255-265;
 1991 Jul. Includes references.
 
 Language:  English
 
 Descriptors: Triticum aestivum; Glycine max; Cell suspensions;
 Cell cultures; Lines; Line differences; Susceptibility;
 Herbicide resistance; Phytotoxicity; Isoxaben; Dichlobenil;
 Mode of action; Cell walls; Biosynthesis; Metabolic
 inhibitors; Cell wall components; Cellulose; Glucose; Plasma
 membranes; Cell ultrastructure
 
 Abstract:  The herbicide isoxaben is selectively phytotoxic to
 dicotyledonous plants, whereas most monocots are tolerant. We
 previously selected a soybean cell culture tolerant to
 isoxaben. Some effects of the herbicide on wild-type soybean
 cells, tolerant soybean cells, and wheat cells were compared.
 Cytological observations showed that isoxaben induced some
 disorganization of sensitive soybean cells, especially at the
 plasma membrane-cell wall interface. Tolerant soybean cells
 appeared normal in the presence of isoxaben. The growth of
 wild-type soybean cells was roughly equally sensitive to
 isoxaben as to dichlobenil, a cellulose synthesis inhibitor.
 By comparison, the selected soybean line and a wheat cell
 culture were less sensitive to isoxaben than to dichlobenil.
 Glucose incorporation into acid-insoluble cell wall material
 was more inhibited by isoxaben than by dichlobenil in the
 wild-type soybean cell culture. In the tolerant soybean cell
 culture, the incorporation was slightly inhibited by isoxaben,
 but remained sensitive to dichlobenil. In the wheat cell
 culture, dichlobenil was also more inhibitory but only at high
 concentrations. Other compounds, inhibitors of cellulose
 biosynthesis, of glycosylation of lipids or protein, or of
 cell division, either had no effect on the synthesis of acid-
 insoluble cell wall material or exerted apparently unspecific
 inhibitions. The results are consistent with isoxaben
 inhibiting the synthesis of a cell wall polysaccharide, which
 could be cellulose.
 
 
 94                                     NAL Call. No.: 450 AN7
 Effects of mecoprop (an auxin analogue) on ethylene evolution
 and epinasty in two biotypes of Stellaria media.
 Coupland, D.; Jackson, M.B.
 London : Academic Press; 1991 Aug.
 Annals of botany v. 68 (2): p. 167-172; 1991 Aug.  Includes
 references.
 
 Language:  English
 
 Descriptors: Stellaria media; Lycopersicon esculentum;
 Mecoprop; Herbicide resistance; Phytotoxicity; Ethylene
 production; Epinasty; Biotypes; Genetic variation
 
 Abstract:  Petiolar epinasty and the production of ethylene
 (ethene) were studied in chickweed biotypes, Stellaria media,
 treated with the herbicide and auxin analogue (RS)-2-(4-
 chloro-o-tolyloxy)propionic acid, potassium salt, common name
 mecoprop. This compound caused severe epinasty and stimulated
 the production of ethylene from shoot explants. However, when
 intact plants were treated with ethylene, the leaves became
 only slightly epinastic. The ethylene precursor, 1-
 aminocyclopropane-1-carboxylic acid (ACC), at concentrations
 which stimulated the release of ethylene, was equally
 ineffective in causing epinasty. Furthermore, 2,5-
 norbornadiene, a specific, competitive inhibitor of ethylene
 action, only partly alleviated mecoprop-induced epinasty. The
 responses observed in chickweed were compared with those
 produced in tomato plants. ACC induced epinasty in tomato
 within 2 h and these symptoms were completely inhibited by
 norbornadiene. However, as in chickweed, the inhibitor gave
 only partial reversal of mecoprop-induced epinasty, implying
 that the epinastic response caused by the herbicide was not
 attributable to ethylene alone. We therefore suggest that
 mecoprop-induced epinasty is a result of the combined
 ethylene-stimulating and growth-promoting properties of the
 herbicide. Mecoprop-stimulated ethylene evolution was
 initially significantly greater in a herbicide-resistant,
 compared with a more susceptible biotype of chickweed. The
 significance of this finding is discussed in relation to the
 mechanism of mecoprop resistance in chickweed.
 
 
 95                                    NAL Call. No.: 450 P692
 Effects on photosystem II function, photoinhibition, and plant
 performance of the spontaneous mutation of serine-264 in the
 photosystem II reaction center D1 protein in triazine-
 resistant Brassica napus L.
 Sundby, C.; Chow, W.S.; Anderson, J.M.
 Rockville, MD : American Society of Plant Physiologists, 1926-
 ; 1993 Sep. Plant physiology v. 103 (1): p. 105-113; 1993 Sep. 
 Includes references.
 
 Language:  English
 
 Descriptors: Brassica napus; Mutations; Photoinhibition;
 Photosystem ii; Serine; Triazine herbicides; Weed control;
 Yield losses; Herbicide resistance
 
 Abstract:  Wild-type and an atrazine-resistant biotype of
 Brassica napus, in which a glycine is substituted for the
 serine-264 of the D1 protein, were grown over a wide range of
 constant irradiances in a growth cabinet. In the absence of
 serine-264, the function of photosystem II (PSII) was changed
 as reflected by changes in chlorophyll fluorescence parameters
 and in photosynthetic oxygen-evolving activity. The
 photochemical quenching coefficient was lower, showing that a
 larger proportion of the primary quinone acceptor is reduced
 at all irradiances. At low actinic irradiances, the
 nonphotochemical quenching coefficient was higher, showing a
 greater tendency for heat emission. Decreased rates of light-
 limited photosynthesis (quantum yield) and lower oxygen yields
 per single-turnover flash were also observed. These changes
 were observed even when the plants had been grown under low
 irradiances, indicating that the changes in PSII function are
 direct and not consequences of photoinhibition. In spite of
 the lowered PSII efficiency under light-limiting conditions,
 the light-saturated photosynthesis rate of the atrazine-
 resistant mutant was similar to that of the wild type. An
 enhanced susceptibility to photoinhibition was observed for
 the atrazine-resistant biotype compared to the wild type when
 plants were grown under high and intermediate, but not low,
 irradiance. We conclude that the replacement of serine by
 glycine in the D1 protein has a direct effect on PSII
 function, which in turn causes increased photoinhibitory
 damage and increased rates of turnover of the D1 protein. Both
 the intrinsic lowering of light-limited photosynthetic
 efficiency and the increased sensitivity to photoinhibition
 probably contribute to reduced crop yields in the field, to
 different extents, depending on growth conditions.
 
 
 96                                    NAL Call. No.: 442.8 Z8
 Engineering 2,4-D resistance into cotton.
 Bayley, C.; Trolinder, N.; Ray, C.; Morgan, M.; Quesenberry,
 J.E.; Ow, D.W. Berlin, W. Ger. : Springer International; 1992.
 Theoretical and applied genetics v. 83 (5): p. 645-649; 1992. 
 Includes references.
 
 Language:  English
 
 Descriptors: Gossypium hirsutum; Nicotiana tabacum;
 Agrobacterium tumefaciens; Alcaligenes; Genetic
 transformation; Transgenics; Gene transfer; Genes;
 Oxidoreductases; 2,4-d; Herbicide resistance; Inheritance;
 Enzyme activity
 
 Abstract:  To reduce damage by drift-levels of the herbicide
 2,4-dichlorophenoxyacetic acid, we have engineered the 2,4-D
 resistance trait into cotton (Gossypium hirsutum L.). The 2,4-
 D monooxygenase gene tfdA from Alcaligenes eutrophus plasmid
 pJP5 was isolated, modified and expressed in transgenic
 tobacco and cotton plants. Analyses of the transgenic progeny
 showed stable transmission of the chimeric tfdA gene and
 production of active 2,4-D monooxygenase. Cotton plants
 obtained were tolerant to 3 times the field level of 2,4-D
 used for wheat, corn, sorghum and pasture crops.
 
 
 97                                     NAL Call. No.: QD1.A45
 Engineering crop resistance to the naturally occurring
 glutamine synthetase inhibitor phophinothricin.
 Mullner, H.; Eckes, P.; Donn, G.
 Washington, D.C. : The Society; 1993.
 ACS Symposium series - American Chemical Society (524): p.
 38-47; 1993.  In the series analytic: Pest control with
 enhanced environmental safety / edited by S.O. Duke, J.J.
 Menn, and J.R. Plimmer.  Includes references.
 
 Language:  English
 
 Descriptors: Weed control; Herbicide resistance; Genetic
 engineering; Gene transfer; Glufosinate
 
 Abstract:  Chemical plant protection will be always needed,
 but the application of gene technology can reduce the impact
 of agriculture to the environment and offer new attractive
 systems for weed control to the farmer. The non-selective
 herbicide glufosinate exhibit desirable properties, which
 makes it suitable for weed control in crops. By transferring a
 microbial resistance gene from the producer of the active
 principle of glufosinate, sensitive crops like corn, oilseed-
 rape, soy bean and sugarbeet could be made resistant. In
 comparison to present, on soil herbicides based weed control
 systems, the flexibility in the application of the post-
 emergent foliar herbicide glufosinate in resistant crops comes
 closer to an ideal system. The introduction of this new system
 will be another important step towards an agriculture with
 reduced impact on the environment.
 
 
 98                                NAL Call. No.: SB123.57.M64
 Engineering microbial herbicide detoxification genes in higher
 plants. Lyon, B.R.
 Molecular approaches to crop improvement / edited by E.S.
 Dennis and D.J. Llewellyn. p. 79-108; 1991. (Plant gene
 research).  Literature review. Includes references.
 
 Language:  English
 
 Descriptors: Crops; Nicotiana tabacum; Genetic engineering;
 Transgenics; Genetic transformation; Herbicide resistance;
 Herbicides; 2,4-d; Enzymes; Microbial degradation; Oxygenases;
 Genes; Alcaligenes; Literature reviews
 
 
 99                                    NAL Call. No.: 442.8 Z8
 Enhanced oxidative-stress defense in transgenic potato
 expressing tomato Cu,Zn superoxide dismutases.
 Perl, A.; Perl-Treves, R.; Galili, S.; Aviv, D.; Shalgi, E.;
 Malkin, S.; Galun, E.
 Berlin, W. Ger. : Springer International; 1993 Jan.
 Theoretical and applied genetics v. 85 (5): p. 568-576; 1993
 Jan.  Includes references.
 
 Language:  English
 
 Descriptors: Solanum tuberosum; Lycopersicon esculentum;
 Genetic transformation; Transgenics; Gene transfer; Dna;
 Superoxide dismutase; Copper; Zinc; Gene expression; Enzyme
 activity; Herbicide resistance; Paraquat; Oxygen;
 Phototoxicity; Photosynthesis; Stress; Roots; Shoots; Organ
 culture
 
 Abstract:  The two cDNAs coding for the cytosolic (cyt) and
 the chloroplast-located (chl) Cu,Zn superoxide dismutases
 (SODs) of tomato (Perl-Treves et al. 1988) were cloned into
 respective binary vectors and mobilized into Agrobacterium
 strains. Potato tuber discs were infected with either of the
 two agrobacterial strains and cultured on selective medium
 containing kanaymcin. The integration of either of the cyt or
 the chl SOD transgenes was verified by Southern-blot
 hybridization. The enzymatic activity of the additional tomato
 chl Cu,Zn SOD could be distinguished from endogenous SOD
 activity since the latter isozyme migrated faster on SOD-
 activity gels. Several transgenic potato lines harboring
 either the cyt or the chl SOD genes of tomato showed elevated
 tolerance to the superoxide-generating herbicide paraquat
 (methyl viologen). After exposure of shoots to paraquat,
 tolerance was recorded either by scoring symptoms visually or
 by measurements of photosynthesis using the photoacoustic
 method. Root cultures from transgenic lines that harbored the
 additional cyt Cu,Zn SOD gene of tomato were tolerant to
 methyl viologen up to 10(-5) M; a lower tolerance was recorded
 in roots of transgenic lines that expressed the additional chl
 Cu,Zn SOD of tomato.
 
 
 100                                  NAL Call. No.: SB610.W39
 Environmental concerns with the development of herbicide-
 tolerant plants. Goldburg, R.J.
 Champaign, Ill. : The Society; 1992 Jul.
 Weed technology : a journal of the Weed Science Society of
 America v. 6 (3): p. 647-652; 1992 Jul.  Paper presented at
 the Symposium, "Development of Herbicide-Resistant Crop
 Cultivars", Weed Science Society of America, February 6, 1991,
 Louisville, Kentucky.  Includes references.
 
 Language:  English
 
 Descriptors: Transgenic plants; Crops; Forest trees; Herbicide
 resistance; Herbicides; Weed control; Environmental impact;
 Groundwater pollution; Public health; Food safety; Nontarget
 effects; Private sector; Public sector; Policy
 
 
 101                                  NAL Call. No.: SB610.W39
 EPA's response to resistance management and herbicide--
 tolerant crop issues. Horne, D.M.
 Champaign, Ill. : The Society; 1992 Jul.
 Weed technology : a journal of the Weed Science Society of
 America v. 6 (3): p. 657-661; 1992 Jul.  Paper presented at
 the Symposium, "Development of Herbicide-Resistant Crop
 Cultivars", Weed Science Society of America, February 6, 1991,
 Louisville, Kentucky.  Includes references.
 
 Language:  English
 
 Descriptors: U.S.A.; Transgenic plants; Herbicide resistance;
 Public agencies; Biotechnology; Regulation; Legislation
 
 
 102                                  NAL Call. No.: HT401.A36
 Ethical and environmental consideration in the release of
 herbicide resistant crops.
 Dekker, J.; Comstock, G.
 Gainesville, Fla. : Agriculture and Human Values, Inc; 1992.
 Agriculture and human values v. 9 (3): p. 31-43; 1992. 
 Includes references.
 
 Language:  English
 
 Descriptors: Herbicide resistance; Ethics; Risk; Crop
 production; Economic viability
 
 
 103                                  NAL Call. No.: SB951.P49
 Ethylene biosynthesis following foliar application of picloram
 to biotypes of wild mustard (Sinapis arvensis L.) susceptible
 or resistant to auxinic herbicides.
 Hall, J.C.; Alam, S.M.M.; Murr, D.P.
 Orlando, Fla. : Academic Press; 1993 Sep.
 Pesticide biochemistry and physiology v. 47 (1): p. 36-43;
 1993 Sep.  Includes references.
 
 Language:  English
 
 Descriptors: Sinapis arvensis; Biotypes; Herbicide resistance;
 Susceptibility; Picloram; Biosynthesis; Ethylene production;
 Acc; Growth regulators; Enzymes; Enzyme activity; Epinasty
 
 Abstract:  Following foliar application of picloram (100 g
 a.i. ha(-1)) to biotypes of wild mustard (Sinapis arvensis L.)
 resistant (R) or susceptible (S) to auxinic herbicides,
 ethylene and its precursors, ACC (1-aminocyclopropane-1-
 carboxylic acid) and MAAC
 (1-malonylaminocyclopropane-1-carboxylic acid), as well as ACC
 synthase were quantified. Severe epinasty occurred within 24
 hr after picloram was applied to the S biotype with
 concomitant increases in ACC synthase, ACC, MACC, and
 ethylene. No epinasty occurred in the R biotype, nor was there
 an increase above basal levels of ACC synthase, ACC, MACC, and
 ethylene in this biotype. Both biotypes became epinastic when
 fumigated with 120 microliter liter(-1) of ethylene.
 Furthermore, when the tissues from both biotypes were supplied
 with exogenous ACC (1 millimole) after pretreatment with
 aminooxyacetic acid (1 millimole), an inhibitor of ACC
 synthase, both biotypes produced ethylene thereby indicating
 that ethylene-forming enzyme was not impaired in the resistant
 biotype. These results suggest that picloram-induced ethylene
 biosynthesis in the S biotype of wild mustard results from de
 novo synthesis of ACC synthase; however, this is not the case
 in the R biotype. Furthermore, sensitivity differences between
 the two biotypes are related to regulation of picloram-induced
 ethylene biosynthesis and resistance may be due to a different
 interaction of the herbicide with primary target site(s) such
 as the auxin-binding protein(s).
 
 
 104                                   NAL Call. No.: 79.9 W52
 Evaluating wild oat seed collections for herbicide resistance.
 Trunkle, P.A.; Fay, P.K.; Dyer, W.E.; Davis, E.S.
 Reno, Nev. : The Society; 1992.
 Proceedings - Western Society of Weed Science v. 45: p. 53-54;
 1992.  Meeting held March 10-12, 1992, in Salt Lake City,
 Utah.
 
 Language:  English
 
 Descriptors: Avena sativa; Herbicide resistance
 
 
 105                                    NAL Call. No.: 450 C16
 Evaluation of oat germplasm for resistance to diclofop-methyl.
 Kibite, S.; Harker, K.N.
 Ottawa : Agricultural Institute of Canada; 1991 Apr.
 Canadian journal of plant science; Revue canadienne de
 phytotechnie v. 71 (2): p. 491-495; 1991 Apr.  Includes
 references.
 
 Language:  English
 
 Descriptors: Alberta; Australia; Avena sativa; Avena fatua;
 Genotypes; Variety trials; Germplasm; Selection; Diclofop;
 Herbicide resistance; Plant breeding
 
 
 106                                  NAL Call. No.: SB951.P49
 Evaluation of paraquat resistance mechanisms in Conyza.
 Norman, M.A.; Fuerst, E.P.; Smeda, R.J.; Vaughn, K.C.
 Orlando, Fla. : Academic Press; 1993 Jul.
 Pesticide biochemistry and physiology v. 46 (3): p. 236-249;
 1993 Jul. Includes references.
 
 Language:  English
 
 Descriptors: Conyza bonariensis; Biotypes; Herbicide
 resistance; Susceptibility; Paraquat; Resistance mechanisms;
 Enzymes; Glutathione reductase (nad(p)h); Superoxide
 dismutase; Enzyme activity; Metabolic detoxification;
 Photosystem i
 
 Abstract:  Experiments were conducted to determine the
 mechanism(s) of paraquat 1,1'-dimethyl-4, 4'-bipyridinium ion)
 resistance in a biotype of hairy fleabane (Conyza bonariensis
 (L.) Cronq.). Thin-layer chromatographic analysis of leaf
 extracts indicated that paraquat is not metabolized in either
 the resistant (R) or the sensitive (S) biotype. Three in vitro
 studies demonstrated that electron transfer from the
 photosystem I (PSI) donor FA/FB) to paraquat is similar in
 both biotypes as was the amount and character of the two FA/FB
 iron-sulfur clusters. The relative activities of the stromal
 enzymes superoxide dismutase, ascorbate peroxidase, and
 glutathione reductase, which can detoxify paraquat-generated
 noxious oxygen species, were determined following separation
 by polyacrylamide gel electrophoresis. Of these enzymes, only
 an increase in ascorbate peroxidase activity (28%) was
 observed in stromal extracts of the R (relative to S) biotype.
 These data indicate that the 100-fold level of paraquat
 resistance observed in leaves of the R biotype of Conyza is
 not due to metabolic detoxification, an altered insensitive)
 site of action. and/or enhanced activities of stromal enzymes.
 Paraquat-induced chlorosis (an indicator of sensitivity) was
 similar in illuminated chloroplast preparations of both
 biotypes indicating that the resistance factor is located
 outside of the chloroplast's envelope. Similar rates of
 paraquat-induced chlorosis were also observed in illuminated
 protoplast preparations of both biotypes; however, leaf
 sections (1 mm width) of the R biotype exhibited a degree of
 paraquat resistance (81-fold) very similar to that exhibited
 by whole leaves. These data suggest that resistance is due to
 a sequestration mechanism that prevents paraquat from
 diffusing to PSI, the site of paraquat action. The
 sequestration mechanism appears to require a structurally
 intact cell wall to be functional.
 
 
 107                                  NAL Call. No.: QH301.A76
 Evaluation of post-emergence herbicides for forestry seedbeds.
 Clay, D.V.; Goodall, J.S.; Williamson, D.R.
 Wellesbourne, Warwick : The Association of Applied Biologists;
 1992. Aspects of applied biology (29): p. 139-148; 1992.  In
 the series analytic: Vegetation management in forestry,
 amenity and conservation areas. Paper presented at the
 conference of the Association, April 7-9, 1992, University of
 York, England.  Includes references.
 
 Language:  English
 
 Descriptors: England; Betula pendula; Larix leptolepis; Picea
 sitchensis; Alnus glutinosa; Forest nurseries; Seedbeds; Field
 experimentation; Herbicide resistance; Herbicides; Injuries;
 Phytotoxicity; Pot experimentation
 
 
 108                                     NAL Call. No.: SB1.H6
 Evaluations and correlated responses for resistance to
 chloramben herbicide in cucumber.
 Staub, J.E.; Knerr, L.D.; Weston, L.A.
 Alexandria, Va. : American Society for Horticultural Science;
 1991 Jul. HortScience v. 26 (7): p. 905-908; 1991 Jul. 
 Includes references.
 
 Language:  English
 
 Descriptors: Wisconsin; Cucumis sativus; Germplasm;
 Collections; Screening; Herbicide resistance; Chloramben; Crop
 damage; Phytotoxicity
 
 Abstract:  The U.S. cucumber germplasm collection (753
 accessions) and U.S. adapted processing cucumber (Cucumis
 sativus L.) inbreds and hybrids were surveyed for response to
 6.7 kg ae/ha of chloramben. Nine plant introductions (PI
 165952, 173892, 179676, 275411, 277741, 279464, 279465,
 436609, and 482464) were classified as tolerant to chloramben,
 based on percentage and rate of field emergence and seedling
 vigor. All adapted strains evaluated were susceptible to
 chloramben injury. The chloramben-tolerant accessions (C0)
 were subjected to two cycles of recurrent half-sib family
 selection that resulted in 11 C2 families. These families, a
 susceptible adapted line (WI 2870), and the resistant PI
 436609 were evaluated in the field (6.7 kg ae/ha) and
 laboratory (0.0, 0.01, and 0.0001 M) for response to
 chloramben challenge. Significant (P = 0.05) differences
 between families were observed for percentage emergence and
 phytotoxicity ratings. Correlations between emergence and
 phytotoxicity ratings at two dates were low (r2 = -0.32 and
 -0.05). Significant (P = 0.05) interfamily differences were
 also recorded for percentage germination, hypocotyl length,
 primary root length, and number of lateral roots in the
 laboratory. Correlated responses between these growth
 variables were high (r2 = 0.78 to 0.84), but correlations
 between field and laboratory observations were low (r2 = -
 0.31 to 0.24). We hypothesize that the genetic response to
 chloramben challenge under laboratory conditions depends on
 the concentration of the chemical administered. Chemical name
 used: 3-amino-2, 5-dichlorobenzoic acid (chloramben).
 
 
 109                                  NAL Call. No.: QK710.P62
 Expression and stability of amplified genes encoding
 5-enolpyruvylshikimate-3-phosphate synthase in glyphosate-
 tolerant tobacco cells.
 Wang, Y.; Jones, J.D.; Weller, S.C.; Goldsbrough, P.B.
 Dordrecht : Kluwer Academic Publishers; 1991 Dec.
 Plant molecular biology : an international journal on
 molecular biology, biochemistry and genetic engineering v. 17
 (6): p. 1127-1138; 1991 Dec. Includes references.
 
 Language:  English
 
 Descriptors: Nicotiana tabacum; Genes; Ligases; Nucleotide
 sequences; Amino acid sequences; Amplification; Glyphosate;
 Herbicide resistance; Gene expression; Messenger  RNA; Cell
 lines; Regeneration
 
 Abstract:  Two distinct cDNAs for 5-enolpyruvylshikimate-3-
 phosphate synthase (EPSPS) were obtained from a glyphosate-
 tolerant tobacco cell line. The cDNAs were 89% identical and
 the predicted sequences of the mature proteins were greater
 than 83% identical with EPSPS proteins from other plants.
 Tobacco EPSPS proteins were more similar to those from tomato
 and petunia than Arabidopsis. One cDNA clone, EPSPS-1,
 represented a gene that was amplified in glyphosate-tolerant
 cells, while the gene for EPSPS-2 was unaltered in these
 cells. Consequently, EPSPS-1 mRNA was more abundant in
 tolerant than unselected cells, whereas EPSPS-2 mRNA was at
 relatively constant levels in these cell lines. Exposure of
 unselected cells and tobacco leaves to glyphosate produced a
 transient increase in EPSPS mRNA. However, glyphosate-tolerant
 cells containing amplified copies of EPSPS genes did not show
 a similar response following exposure to glyphosate. A
 significant proportion of the EPSPS gene amplification was
 maintained when tolerant cells were grown in the absence of
 glyphosate for eight months. Plants regenerated from these
 cells also contained amplified EPSPS genes.
 
 
 110                                   NAL Call. No.: 450 P692
 Expression of Erwinia uredovora phytoene desaturase in
 Synechococcus PCC7942 leading to resistance against a
 bleaching herbicide.
 Windhovel, U.; Geiges, B.; Sandmann, G.; Boger, P.
 Rockville, MD : American Society of Plant Physiologists, 1926-
 ; 1994 Jan. Plant physiology v. 104 (1): p. 119-125; 1994 Jan. 
 Includes references.
 
 Language:  English
 
 Descriptors: Synechococcus; Erwinia uredovora; Genetic
 transformation; Structural genes; Oxygenases; Recombinant 
 DNA; Promoters; Gene expression; Herbicide resistance;
 Norflurazon; Carotenoids; Biosynthesis; Phytoene
 
 Abstract:  The gene coding for phytoene desaturase of the
 bacterium Erwinia uredovora (crtI) was inserted into the
 chromosome of the cyanobacterium Synechococcus PCC7942 strain
 R2-PIM8. For expression of crtI in the heterologous host, two
 constructs with different promoters were introduced into
 Synechococcus. In the first, crtI was fused to the 5' region
 of the psbA gene of the xanthophycean microalga Bumilleriopsis
 filiformis. The second construct carried crtI inserted
 downstream of the neomycin phosphotransferase II gene (nptII)
 from the transposon Tn5. Expression of crtI under the control
 of the respective promoter was shown by immunodetection of the
 gene product. The functionality of the heterologously
 expressed phytoene desaturase CRTI in the transformants was
 demonstrated by enzymic assays. The transformants acquired
 very strong resistance toward the bleaching herbicide
 norflurazon.
 
 
 111                                  NAL Call. No.: 442.8 G28
 Expression of the maize MnSod (Sod3) gene in MnSOD-deficient
 yeast rescues the mutant yeast under oxidative stress.
 Zhu, D.; Scandalios, J.G.
 Baltimore, Md. : Genetics Society of America; 1992 Aug.
 Genetics v. 131 (4): p. 803-809; 1992 Aug.  Includes
 references.
 
 Language:  English
 
 Descriptors: Zea mays; Saccharomyces cerevisiae; Structural
 genes; Superoxide dismutase; Manganese; Genetic
 transformation; Gene transfer; Gene expression; Mitochondria;
 Enzyme activity; Oxygen; Free radicals; Paraquat; Herbicide
 resistance; Stress; Mutants; Induced mutations;
 Complementation
 
 Abstract:  Superoxide dismutases (SOD) are ubiquitous in
 aerobic organisms and are believed to play a significant role
 in protecting cells against the toxic, often lethal, effect of
 oxygen free radicals. However, direct evidence that SOD does
 in fact participate in such a protective role is scant. The
 MnSOD-deficient yeast strain (Sod2d) offered an opportunity to
 test the functional role of one of several SOD isozymes from
 the higher plant maize in hopes of establishing a functional
 bioassay for other SODs. Herein, we present evidence that
 MnSOD functions to protect cells from oxidative stress and
 that this function is conserved between species. The maize
 Sod3 gene was introduced into the yeast strain Sod2d where it
 was properly expressed and its product processed into the
 yeast mitochondrial matrix and assembled into the functional
 homotetramer. Most significantly, expression of the maize Sod3
 transgene in yeast rendered the transformed yeast cells
 resistant to paraquat-induced oxidative stress by
 complementing the MnSOD deficiency. Furthermore, analyses with
 various deletion mutants of the maize SOD-3 transit peptide in
 the MnSOD-deficient yeast strain indicate that the initial
 portion (about 8 amino acids) of the maize transit peptide is
 required to direct the protein into the yeast mitochondrial
 matrix in vivo to function properly. These findings indicate
 that the functional role of maize MnSOD is conserved and
 dependent on its proper subcellular location in the
 mitochondria of a heterologous system.
 
 
 112                                   NAL Call. No.: QH442.B5
 Fertile, transgenic oat plants.
 Somers, D.A.; Rines, H.W.; Gu, W.; Kaeppler, H.F.; Bushnell,
 W.R. New York, N.Y. : Nature Publishing Company; 1992 Dec.
 Bio/technology v. 10 (12): p. 1589-1594; 1992 Dec.  Includes
 references.
 
 Language:  English
 
 Descriptors: Avena sativa; Transgenics; Genetic
 transformation; Callus; Direct  DNAuptake; Reporter genes;
 Beta-glucuronidase; Phosphotransferases; Glufosinate;
 Herbicide resistance; Regenerative ability; Fertility;
 Inheritance; Histoenzymology
 
 
 113                                  NAL Call. No.: 470 SCI24
 First gene-splice wheat.
 Washington, D.C. : Science Service :.; 1992 Jun06.
 Science news v. 141 (23): p. 379; 1992 Jun06.
 
 Language:  English
 
 Descriptors: Triticum aestivum; Genetic engineering; Herbicide
 resistance
 
 
 114                                  NAL Call. No.: SB610.W39
 Flurtamone for wild mustard (Sinapis arvensis) control in
 canola (Brassica napus and B. campestris).
 Wall, D.A.
 Champaign, Ill. : The Weed Science Society of America; 1992
 Oct. Weed technology : a journal of the Weed Science Society
 of America v. 6 (4): p. 878-883; 1992 Oct.  Includes
 references.
 
 Language:  English
 
 Descriptors: Canada; Cabt; Brassica napus; Brassica
 campestris; Cultivars; Herbicide resistance; Flurtamone;
 Application rates; Crop density; Crop yield; Sinapis arvensis;
 Weed control; Chemical control
 
 
 115                                    NAL Call. No.: SB1.J66
 Frequency of iron application influences bermudagrass
 tolerance to herbicides. Carrow, R.N.; Johnson, B.J.
 Washington, D.C. : Horticultural Research Institute; 1992 Dec.
 Journal of environmental horticulture v. 10 (4): p. 228-231;
 1992 Dec. Includes references.
 
 Language:  English
 
 Descriptors: Cynodon dactylon; Cynodon; Hybrids; Iron
 fertilizers; Lawns and turf; Crop damage; Weed control;
 Chemical control; Herbicide resistance; Imazaquin; Metribuzin;
 Msma
 
 
 116                                   NAL Call. No.: 79.8 W41
 Fun with mutants: applying genetic methods to problems of weed
 physiology. Christianson, M.L.
 Champaign, Ill. : Weed Science Society of America; 1991 Jul.
 Weed science v. 39 (3): p. 489-496; 1991 Jul.  Paper presented
 at the "Symposium on New Techniques adn Advances in Weed
 Physiology and Molecular Biology," February 6, 1991,
 Louisville, Kentucky.  Includes references.
 
 Language:  English
 
 Descriptors: Weeds; Weed biology; Mutants; Herbicide
 resistance; Mode of action; Chlorsulfuron; Mutagens; Induced
 mutations; Mutagenesis; Pollen; Seeds; Screening; Selection
 criteria; Molecular genetics
 
 Abstract:  Genetics can be a powerful adjunct to just about
 any kind of physiological study, including weed physiology or
 weed/herbicide interactions. Making, mapping, and reverting
 mutations is simple and straightforward. Making mutants can be
 as simple as isolating variant individuals from the "wild", as
 uncomplicated as doing seed mutagenesis in your laboratory, or
 as sneaky as recovering mutants as sectors in whole plants.
 The overall principles for successful development of a
 protocol for seed mutagenesis of weeds are described and
 potential problem areas noted. These generalities are
 illustrated with a specific case history, that of
 chlorsulfuron. Although chlorsulfuron is accurately described
 as an inhibitor of the synthesis of branched chain amino
 acids, careful physiological examination suggests that it
 kills plant cells, not by starvation for amino acids, but by
 active toxicity of a metabolite, alpha-amino butyric acid,
 produced from a precursor available for diversion in cells
 with inhibited acetolactate synthase (EC 4.1.3.18, ALS). The
 story of dominant resistance due to an altered ALS enzyme is
 well known; analysis using additional mutants fleshes out the
 story of how chlorsulfuron works. Such analysis has the
 potential to help unravel other problems in weed physiology.
 
 
 117                                  NAL Call. No.: QK710.P62
 Functional analysis of the two homologous psbA gene copies in
 Synechocystis PCC 6714 and PCC 6803.
 Bouyoub, A.; Vernotte, C.; Astier, C.
 Dordrecht : Kluwer Academic Publishers; 1993 Jan.
 Plant molecular biology : an international journal on
 molecular biology, biochemistry and genetic engineering v. 21
 (2): p. 249-258; 1993 Jan. Includes references.
 
 Language:  English
 
 Descriptors: Cyanobacteria; Multiple genes; Structural genes;
 Proteins; Photosystem ii; Mutations; Herbicide resistance;
 Thylakoids; Photosynthesis; Gene mapping; Restriction mapping;
 Light intensity
 
 Abstract:  The cyanobacteria Synechocystis 6803 and 6714
 contain three genes (psbA) coding for the D1 protein. This
 protein is an essential subunit of photosystem II (PSII) and
 is the target for herbicides. We have used herbicide-resistant
 mutants to study the role of the two homologous copies of the
 psbA genes in both strains (the third copy is not expressed).
 Several herbicide resistance mutations map within the psbAI
 gene in Synechocystis 6714 (G. Ajlani et al., Plant Mol. Biol.
 13 (1989): 469-479). We have looked for mutations in copy II.
 Results show that in Synechocystis 6714, only psbAI contains
 herbicide resistance mutations. Relative expression of psbAI
 and psbAII has been measured by analysing the proportions of
 resistant and sensitive D1 in the thylakoid membranes of the
 mutants. In normal growth conditions, 95% resistant D1 and 5%
 sensitive D1 were found. In high light conditions, expression
 of psbAII was enhanced, producing 15% sensitive D1. This
 enhancement is specifically due to high light and not to the
 decrease of D1 concentration caused by photoinhibition. Copy I
 of Synechocystis 6714 corresponds to copy 2 of Synechocystis
 6803 since it was always psbA2 which was recombined in
 Synechocystis 6803 transformants. PSII of the transformant
 strains was found to be 95% resistant to herbicides as in
 resistant mutants of Synechocystis 6714.
 
 
 118                                  NAL Call. No.: QK710.P68
 Functional expression of the Erwinia uredovora carotenoid
 biosynthesis gene crtl in transgenic plants showing an
 increase of beta-carotene biosynthesis activity and resistance
 to the bleaching herbicide norflurazon. Misawa, N.; Yamano,
 S.; Linden, H.; Felipe, M.R. de; Lucas, M.; Ikenaga, H.;
 Sandmann, G.
 Oxford : Blackwell Scientific Publishers and BIOS Scientific
 Publishers in association with the Society for Experimental
 Biology, c1991-; 1993 Nov. The Plant journal : for cell and
 molecular biology v. 4 (5): p. 833-840; 1993 Nov.  Includes
 references.
 
 Language:  English
 
 Descriptors: Nicotiana tabacum; Transgenics; Biosynthesis;
 Carotenoids; Herbicide resistance; Norflurazon
 
 
 119                                  NAL Call. No.: SB610.W39
 Future impact of crops with modified herbicide resistance.
 Wyse, D.L.
 Champaign, Ill. : The Society; 1992 Jul.
 Weed technology : a journal of the Weed Science Society of
 America v. 6 (3): p. 665-668; 1992 Jul.  Paper presented at
 the Symposium, "Development of Herbicide-Resistant Crop
 Cultivars", Weed Science Society of America, February 6, 1991,
 Louisville, Kentucky.  Includes references.
 
 Language:  English
 
 Descriptors: Transgenic plants; Crops; Herbicide resistance;
 Biotechnology; Weed control; Development plans
 
 
 120                                 NAL Call. No.: QD341.A2N8
 Gene rescue in plants by direct gene transfer of total genomic
 DNA into protoplasts.
 Gallois, P.; Lindsey, K.; Malone, R.; Kreis, M.; Jones, M.G.K.
 Oxford : IRL Press; 1992 Aug11.
 Nucleic acids research v. 20 (15): p. 3977-3982; 1992 Aug11. 
 Includes references.
 
 Language:  English
 
 Descriptors: Nicotiana tabacum; Arabidopsis thaliana; Beta
 vulgaris; Gene transfer; Protoplasts; Genes; Isolation;
 Mutants; Herbicide resistance; Chlorsulfuron; In vitro
 selection; Electroporation; Genetic transformation; Plasmids;
 Kanamycin; Drug resistance; Direct  DNAuptake; Transgenic
 plants; Segregation
 
 Abstract:  To study the possibility of gene rescue in plants
 by direct gene transfer we chose the Arabidopsis mutant GH50
 as a source of donor DNA. GH50 is tolerant of chlorsulfuron, a
 herbicide of the sulfonylurea class. Tobacco protoplasts were
 cotransfected with genomic DNA and the plasmid pHP23 which
 confers kanamycin resistance. A high frequency of
 cointegration of the plasmid and the genomic DNA was expected,
 which would allow the tagging of the plant selectable trait
 with the plasmid DNA. After transfection by electroporation
 the protoplasts were cultivated on regeneration medium
 supplemented with either chlorsulfuron or kanamycin as a
 selective agent. Selection on kanamycin yielded resistant
 calluses at an absolute transformation frequency (ATF) of 0.8
 X 10(-3). Selection on chlorsulfuron yielded resistant
 calluses at an ATF of 4.7 X 10(-6). When a selection on
 chlorsulfuron was subsequently applied to the kanamycin
 resistant calluses, 8% of them showed resistance to this
 herbicide. Southern analysis carried out on the herbicide
 resistant transformants detected the presence of the herbicide
 resistance gene of Arabidopsis into the genome of the
 transformed tobacco. Segregation analysis showed the presence
 of the resistance gene and the marker gene in the progeny of
 the five analysed transformants. 3 transformants showed
 evidence of genetic linkage between the two genes. In addition
 we show that using the same technique a kanamycine resistance
 gene from a transgenic tobacco could be transferred into sugar
 beet protoplasts at a frequency of 0.17% of the transformants.
 
 
 121                                  NAL Call. No.: 442.8 Z34
 Gene SNQ2 of Saccharomyces cerevisiae, which confers
 resistance to 4-nitroquinoline-N-oxide and other chemicals,
 encodes a 169 kDa protein homologous to ATP-dependent
 permeases.
 Servos, J.; Haase, E.; Brendel, M.
 Berlin, W. Ger. : Springer International; 1993 Jan.
 M G G : Molecular and general genetics v. 236 (2/3): p.
 214-218; 1993 Jan. The accession number 66732 does not conform
 to standard format.  Includes references.
 
 Language:  English
 
 Descriptors: Saccharomyces cerevisiae; Structural genes; Plant
 proteins; Resistance; Mutagens; Quinolines; Aromatic
 compounds; Sulfometuron; Herbicide resistance; Nucleotide
 sequences; Amino acid sequences; Gene expression; Atp; Binding
 site
 
 Abstract:  The yeast gene SNQ2 confers hyper-resistance to the
 mutagens 4-nitroquinoline-N-oxide (4-NQO) and Triaziquone, as
 well as to the chemicals sulphomethuron methyl and
 phenanthroline when present in multiple copies in
 transformants of Saccharomyces cerevisiae. Subcloning and
 sequencing of a 5.5 kb yeast DNA fragment revealed that SNQ2
 has an open reading frame of 4.5 kb. The putative encoded
 polypeptide of 1501 amino acids has a predicted molecular
 weight of 169 kDa and has several hydrophobic regions.
 Northern analysis showed a transcript of 5.5 kb. Haploid cells
 with a disrupted SNQ2 reading frame are viable. The SNQ2-
 encoded protein has domains believed to be involved in ATP
 binding and is likely to be membrane associated. It most
 probably serves as an ATP-dependent permease.
 
 
 122                                  NAL Call. No.: TA166.T72
 Genes of jeans: biotechnological advances in cotton.
 John, M.E.; Stewart, J.M.
 New York, N.Y. : Elsevier Science Publishing Co; 1992 May.
 Trends in biotechnology v. 10 (5): p. 165-170; 1992 May. 
 Includes references.
 
 Language:  English
 
 Descriptors: Gossypium; Biotechnology; Genetic engineering;
 Selection criteria; Agronomic characteristics; Crop
 management; Improvement; Fiber quality; Modification; Genes
 
 Abstract:  Cotton is a crop of global economic importance. The
 impact of advances in cotton genetic engineering will
 therefore go beyond just altering the patterns of agronomic
 practice to have a major effect on both economic and social
 structures. Although the majority of characteristics currently
 being engineered into cotton (i.e. insect- and herbicide-
 tolerance) relate to improved crop management, the longer-term
 goals of modifying fiber are to improve and develop novel
 properties for the product.
 
 
 123                                  NAL Call. No.: 442.8 G28
 Genetic interactions among Chlamydomonas reinhardtii mutations
 that confer resistance to anti-microtubule herbicides.
 James, S.W.; Lefebvre, P.A.
 Baltimore, Md. : Genetics Society of America; 1992 Feb.
 Genetics v. 130 (2): p. 305-314; 1992 Feb.  Includes
 references.
 
 Language:  English
 
 Descriptors: Chlamydomonas reinhardtii; Loci; Recessive genes;
 Alleles; Mutations; Herbicide resistance; Amiprofos-methyl;
 Oryzalin; Microtubules; Complementation; Gene interaction;
 Flagella; Deuterium oxide; Genetic change
 
 Abstract:  We previously described two types of genetic
 interactions among recessive mutations in the APM1 and APM2
 loci of Chlamydomonas reinhardtii that may reflect a physical
 association of the gene products or their involvement in a
 common structure/process: (1) allele-specific synthetic
 lethality, and (2) unlinked noncomplementation, or dominant
 enhancement. To further investigate these interactions, we
 isolated revertants in which the heat sensitivity caused by
 the apm2-1 mutation is lost. The heat-insensitive revertants
 were either fully or partially suppressed for the drug-
 resistance caused by the apm2-1 allele, In recombination tests
 the revertants behaved as if the suppressing mutation mapped
 within the APM2 locus; the partial suppressors of apm2-1
 herbicide resistance failed to complement apm2-1, leading to
 the conclusion that they were likely to be intragenic
 pseudorevertants. The apm2-1 partial suppressor mutations
 reversed apm1-apm2-1 synthetic lethality in an allele-specific
 manner with respect both to apm1-alleles and apm2-1 suppressor
 mutations. Those apm1- apm2-1rev strains that regained
 viability also regained heat sensitivity characteristic of the
 original apm2-1 mutation, even though the apm2-1 suppressor
 strains were fully heat-insensitive. The Hs+ phenotypes of
 apm2-1 partial suppressors were also reversed by treatment
 with the microtubule-stabilizing agent deuterium oxide (D2O).
 In addition to the above interactions, we observed
 interallelic complementation and phenotypic enhancement of
 temperature conditionality among apm1- alleles. Evidence of a
 role for the products of the two genes in microtubule-based
 processes was obtained from studying flagellar assembly in
 apm1- and apm2- mutants.
 
 
 124                                  NAL Call. No.: 442.8 G28
 Genetic interactions at the FLA10 locus: suppressors and
 synthetic phenotypes that affect the cell cycle and flagellar
 function in Chlamydomonas reinhardtii.
 Lax, F.G. III; Dutcher, S.K.
 Baltimore, Md. : Genetics Society of America; 1991 Jul.
 Genetics v. 128 (3): p. 549-561; 1991 Jul.  Includes
 references.
 
 Language:  English
 
 Descriptors: Chlamydomonas reinhardtii; Induced mutations;
 Mutants; Loci; Gene interaction; Flagella; Motility;
 Temperature; Inhibitor genes; Cell division; Phenotypes;
 Herbicide resistance; Amiprofos-methyl; Oryzalin; Alleles
 
 Abstract:  Through the isolation of suppressors of
 temperature-sensitive flagellar assembly mutations at the
 FLA10 locus of Chlamydomonas reinhardtii, we have identified
 six other genes involved in flagellar assembly. Mutations at
 these suppressor loci, termed SUF1-SUF6, display allele
 specificity with respect to which fla10- mutant alleles they
 suppress. An additional mutation, apm1-122, which confers
 resistance to the plant herbicides amiprophos-methyl and
 oryzalin, was also found to interact with mutations at the
 FLA10 locus. The apm1-122 mutation in combination with three
 fla10- mutant alleles results in synthetic cold-sensitive cell
 division defects, and in combination with an additional
 pseudo-wild-type fla10- allele yields a synthetic temperature-
 sensitive flagellar motility phenotype. Based upon the genetic
 interactions of these loci, we propose that the FLA10 gene
 product interacts with multiple components of the flagellar
 apparatus and plays a role both in flagellar assembly and in
 the cell cycle.
 
 
 125                                  NAL Call. No.: QH442.J69
 Genetic manipulation of crop plants.
 Lindsey, K.
 Amsterdam : Elsevier Science Publishers B.V.; 1992 Oct.
 Journal of Biotechnology v. 26 (1): p. 1-28; 1992 Oct.  In the
 special issue: Plant cell culture / edited by A.H. Scragg. 
 Literature review.  Includes references.
 
 Language:  English
 
 Descriptors: Crops; Genetic engineering; Genetic
 transformation; Genetic resistance; Plant development;
 Herbicide resistance; Literature reviews; Pest resistance
 
 
 126                                  NAL Call. No.: 442.8 Z34
 Genetic study and further biochemical characterization of a
 tobacco mutant that overproduces sterols.
 Maillot-Vernier, P.; Gondet, L.; Schaller, H.; Benveniste, P.;
 Belliard, G. Berlin, W. Ger. : Springer International; 1991
 Dec.
 M G G : Molecular and general genetics v. 231 (1): p. 33-40;
 1991 Dec. Includes references.
 
 Language:  English
 
 Descriptors: Nicotiana tabacum; Mutants; Mutations; Dominance;
 Segregation; Phytosterols; Sterol esters; Lipogenesis; Lipids;
 Droplets; Cytoplasm; Herbicide resistance; Triazole
 herbicides; Callus
 
 Abstract:  A genetic and biochemical characterization is
 presented of a tobacco mutant that was previously shown to
 have an increased sterol content with an accumulation of
 biosynthetic intermediates. We first show that a precise
 regulation of the membrane sterol composition occurs in this
 mutant, via a selective esterification process. Indeed,
 sterols representing the usual end-products of the
 biosynthetic pathway are preferably integrated into the
 membranes as free sterols, whereas most of the intermediates
 pool is esterified and stored in cytoplasmic lipid droplets.
 It is further demonstrated that overproduction of sterols by
 the LAB1-4 mutant is due to a single nuclear and semi-dominant
 mutation. Finally, increase of biosynthesis and esterification
 of unusual sterols are shown to be responsible for the
 resistance of LAB1-4 calli to LAB170 250F, the triazole
 pesticide used to select this mutant. However, differentiated
 LAB1-4 tissues do not express the resistance trait, suggesting
 that sterol biosynthesis might not be the only site of action
 for the triazole at the plant level.
 
 
 127                                    NAL Call. No.: 472 N42
 Genetic weeding and feeding for tobacco plants.
 Bradley, D.
 London, Eng. : New Science Publications; 1992 Jan04.
 New scientist v. 133 (1802): p. 11; 1992 Jan04.
 
 Language:  English
 
 Descriptors: Nicotiana tabacum; Myrothecium verrucaria;
 Genetic engineering; Herbicide resistance
 
 
 128                                  NAL Call. No.: 61.8 SE52
 Genetically altered seed & how it will be distributed.
 Grooms, L.
 Des Plains, Ill. : Scranton Gillette Communications, Inc; 1992
 Nov. Seed world v. 130 (12): p. 8-9, 11-13; 1992 Nov.
 
 Language:  English
 
 Descriptors: Seeds; Genetic engineering; Distribution;
 Herbicide resistance; Pest resistance
 
 
 129                            NAL Call. No.: S494.5.B563B554
 Genetically engineered plants for herbicide resistance.
 Mullineaux, P.M.
 Wallingford, Oxford, UK : CAB International; 1992.
 Biotechnology in agriculture v. 7: p. 75-107; 1992.  In the
 series analytic: Plant genetic manipulation for crop
 protection / edited by A.M.R. Gatehouse, V.A. Hilder and
 Boulter, D.  Includes references.
 
 Language:  English
 
 Descriptors: Crops; Herbicides; Herbicide resistance; Gene
 expression; Genetic engineering; Genetic transformation;
 Vectors; Biochemical pathways; Amino acid metabolism; Protein
 synthesis; Enzyme activity; Genes; Amplification; Structure
 activity relationships; Detoxification; Glutathione
 transferase; Herbicide safeners; Chimerism; Plant protection;
 Amino acid sequences; Mutations
 
 
 130                            NAL Call. No.: S494.5.B563A382
 Genetically-engineered herbicide-resistant crops--a moral
 imperative for world food production.
 Gressel, J.
 Milan, Italy : Teknoscienze,; 1992 Nov.
 Agrofoodindustry hi-tech v. 3 (6): p. 3-7; 1992 Nov.  Includes
 references.
 
 Language:  English
 
 Descriptors: Crops; Herbicide resistance; Genetic engineering;
 Weed control; Herbicides
 
 
 131                                  NAL Call. No.: 442.8 Z34
 Glyphosate selected amplification of the 5-
 enolpyruvylshikimate-3-phosphate synthase gene in cultured
 carrot cells.
 Shyr, Y.Y.J.; Hepburn, A.G.; Widholm, J.M.
 Berlin, W. Ger. : Springer International; 1992 Apr.
 M G G : Molecular and general genetics v. 232 (3): p. 377-382;
 1992 Apr. Includes references.
 
 Language:  English
 
 Descriptors: Daucus carota; Structural genes; Transferases; In
 vitro selection; Glyphosate; Herbicide resistance;
 Amplification; Gene expression; Messenger  RNA; Gene dosage;
 Tissue culture; Cell suspensions
 
 Abstract:  CAR and C1, two carrot (Dacus carota L.) suspension
 cultures of different genotypes, were subjected to stepwise
 selection for tolerance to the herbicide glyphosate [(N-
 phosphonomethyl)glycine]. The specific activity of the target
 enzyme, 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS),
 as well as the mRNA level and copy number of the structural
 gene increased with each glyphosate selection step. Therefore,
 the tolerance to glyphosate is due to stepwise amplification
 of the EPSPS genes. During the amplification process, DNA
 rearrangement did not occur within the EPSPS gene of the CAR
 cell line but did occur during the selection step from 28 to
 35 mM glyphosate for the C1 cell line, as determined by
 Southern hybridization of selected cell DNA following EcoRI
 restriction endonuclease digestion. Two cell lines derived
 from a previously selected glyphosate-tolerant cell line (PR),
 which also had undergone EPSPS gene amplification but have
 been maintained in glyphosate-free medium for 2 and 5 years,
 have lost 36 and 100% of the increased EPSPS activity,
 respectively. Southern blot analysis of these lines confirms
 that the amplified DNA is relatively stable in the absence of
 selection. These studies demonstrate that stepwise selection
 for glyphosate resistance reproducibly produces stepwise
 amplification of the EPSPS genes. The relative stability of
 this amplification indicates that the amplified genes are not
 extrachromosomal.
 
 
 132                                  NAL Call. No.: QK710.P62
 Glyphosate tolerance of cultured Corydalis sempervirens cell
 is acquired by an increased rate of transcription of 5-
 enolpyruvylshikimate 3-phosphate synthase as well as by a
 reduced turnover of the enzyme.
 Hollander-Czytko, H.; Sommer, I.; Amrheim, N.
 Dordrecht : Kluwer Academic Publishers; 1992 Dec.
 Plant molecular biology : an international journal on
 molecular biology, biochemistry and genetic engineering v. 20
 (6): p. 1029-1036; 1992 Dec. Includes references.
 
 Language:  English
 
 Descriptors: Corydalis; Transcription; Gene expression;
 Ligases; Glyphosate; Herbicide resistance; Messenger  RNA;
 Enzyme activity; Genetic regulation; Cell culture
 
 Abstract:  Cell cultures of Corydalis sempervirens, tolerant
 to the herbicide glyphosate, have a 30-40-fold increased level
 of the herbicide's target enzyme 5-enolpyruvylshikimate 3-
 phosphate (EPSP) synthase, a ten-fold enhanced level of the
 corresponding mRNA but no amplification of the gene
 (Hollander-Czytko et al., Plant Mol Biol 11 (1988) 215-220).
 The increase at the transcriptional level is due to a higher
 rate of transcription of the gene, which was observed in run-
 off transcription assays with isolated nuclei. The further
 amplification at the protein level is the result of
 stabilization of the enzyme by the herbicide. In the presence
 of glyphosate the half-life of EPSP synthase was doubled
 leading to higher levels of both protein and enzyme activity.
 Overproduction of the enzyme in adapted cultures is stable at
 the transcriptional level, as cells from adapted cultures
 grown in the absence of glyphosate for three years still
 display an about ten-fold higher enzyme activity and
 transcript level than non-adapted cultures.
 
 
 133                                NAL Call. No.: SB610.2.B74
 Glyphosate-tolerant crops for the future: development, risks
 and benefits. Waters, S.
 Surrey : BCPC Registered Office; 1991.
 Brighton Crop Protection Conference-Weeds v. 1: p. 165-170;
 1991.  Includes references.
 
 Language:  English
 
 Descriptors: Crops; Weed control; Herbicide resistance;
 Tolerance; Glyphosate
 
 
 134                                  NAL Call. No.: SB951.P49
 Graminicide resistance of acetyl-CoA carboxylase from
 ornamental grasses. Catanzaro, C.J.; Burton, J.D.; Skroch,
 W.A.
 Orlando, Fla. : Academic Press; 1993 Feb.
 Pesticide biochemistry and physiology v. 45 (2): p. 147-153;
 1993 Feb. Includes references.
 
 Language:  English
 
 Descriptors: Festuca ovina; Festuca; Cultivars; Erianthus;
 Pennisetum alopecuroides; Panicum virgatum; Sethoxydim;
 Fluazifop; Herbicide resistance; Susceptibility; Acetyl-coa
 carboxylase; Enzyme activity; Atp; Weed control
 
 Abstract:  Blue fescues [Festuca ovina var. glauca (Lam.)
 Koch. and F. amethystina L.] are resistant to graminicides,
 whereas fountain grass [Pennisetum alopecuroides (L.) Spreng.]
 and most other grasses are sensitive. Evidence suggests that
 selective control of grasses by the graminicides fluazifop (an
 aryloxyphenoxypropionate) and sethoxydim (a cyclohexanedione)
 is often due to differential resistance at the primary site of
 action, acetyl-CoA carboxylase (ACCase). ACCase activity was
 obtained from fountain grass and four cultivars of blue fescue
 to determine whether resistance at the whole plant level
 correlated with ACCase resistance in vitro. ACCase activity
 was represented by in vitro incorporation of radioactive
 bicarbonate into an acid-and heat-stable product. Enzyme
 activity was dependent on acetyl-CoA and ATP and was inhibited
 in the presence of avidin, suggesting that activity was due to
 ACCase. Compared to ACCase from fountain grass, ACCase from
 fescues was 70 to 88 times more resistant to fluazifop and 216
 to 422 times more resistant to sethoxydim. Differences of this
 magnitude at the enzyme level may be sufficient to explain
 differential response between blue fescues (resistant) and
 fountain grass (sensitive) at the whole plant level.
 
 
 135                                  NAL Call. No.: 79.9 W52R
 Grass tolerance to imazethapyr.
 Ferrell, M.A.; Koch, D.W.; Ogg, P.J.; Hruby, F.
 S.l. : The Society; 1992.
 Research progress report - Western Society of Weed Science. p.
 III/97-III/98; 1992.  Meeting held on March 9-12, 1992, Salt
 Lake City, Utah.
 
 Language:  English
 
 Descriptors: Wyoming; Grasses; Herbicide resistance;
 Imazethapyr
 
 
 136                                   NAL Call. No.: 79.8 W41
 Growth response of wheat (Triticum aestivum) callus to
 imazapyr and in vitro selection for resistance.
 Heering, D.C.; Guenzi, A.C.; Peeper, T.F.; Claypool, P.L.
 Champaign, Ill. : Weed Science Society of America; 1992 Apr.
 Weed science v. 40 (2): p. 174-179; 1992 Apr.  Includes
 references.
 
 Language:  English
 
 Descriptors: Triticum aestivum; Herbicide resistance;
 Mutations; Callus; In vitro selection; Imazapyr; Application
 rates; Growth rate; Isoleucine; Leucine; Valine; Amino acid
 metabolism; Enzyme inhibitors
 
 Abstract:  Intact wheat plants and wheat calli responded
 similarly to varying concentrations of imazapyr. Fifty percent
 growth inhibition of wheat callus occurred with 0.05
 micromolar imazapyr after 70 d. As imazapyr concentration
 increased from 0 to 10 micromolar, the free isoleucine,
 leucine, and valine decreased from 160 to 35, 260 to 49, and
 310 to 59 pmol mg-1, respectively. Resistant calli, which had
 relative growth rates exceeding a calculated upper prediction
 interval, were obtained by in vitro selection at 2 and 5
 micromolar imazapyr. Resistant calli growing on 2 micromolar
 imazapyr had free isoleucine, leucine, and valine
 concentrations intermediate to the control and susceptible
 callus.
 
 
 137                                    NAL Call. No.: 450 AN7
 Haploid culture and UV mutagenesis in rapid-cycling Brassica
 napus for the generation of resistance to chlorsulfuron and
 Alternaria brassicola. Ahmad, I.; Day, J.P.; MacDonald, M.V.;
 Ingram, D.S.
 London : Academic Press; 1991 Jun.
 Annals of botany v. 67 (6): p. 521-525; 1991 Jun.  Includes
 references.
 
 Language:  English
 
 Descriptors: Brassica napus; Plant breeding; Selection;
 Haploids; Mutagenesis; Ultraviolet radiation; Chlorsulfuron;
 Herbicide resistance; Alternaria brassicicola; Plant
 pathogenic fungi; Disease resistance
 
 Abstract:  The effect of ultra violet (UV) irradiation on
 cultured isolated microspores of rapid cycling Brassica napus
 was investigated. The microspores were highly sensitive to UV,
 with the calculated LD50 being an exposure of 20 s. Viability
 tests suggested that death of the microspores was not
 immediate, but occurred during subsequent incubation (7 d).
 None of the embryos produced following UV-irradiation of
 microspores showed gross morphological variation. A large
 number of regenerants was established from embryoids and grown
 to flowering. These plants set fertile seed after selfing. The
 progenies were assessed for resistance to Alternaria
 brassicicola and a small number showed increased resistance to
 the pathogen, suggesting the generation of novel heritable
 resistance to this pathogen. In vitro selection revealed
 heritable resistance to the herbicide 'Glean' (active
 ingredient chlorsulfuron).
 
 
 138                                 NAL Call. No.: 284.28 W15
 Hardy crops yield herbicide controversy.
 Nazario, S.L.
 New York, N.Y. : Dow Jones; 1991 Aug01.
 The Wall Street journal. p. B1, B4; 1991 Aug01.
 
 Language:  English
 
 Descriptors: U.S.A.; Herbicide resistance; Genetic
 engineering; Bromoxynil; Environmental impact
 
 
 139                                    NAL Call. No.: 450 C16
 Harovinton soybean.
 Buzzell, R.I.; Anderson, T.R.; Hamill, A.S.; Welacky, T.W.
 Ottawa : Agricultural Institute of Canada; 1991 Apr.
 Canadian journal of plant science; Revue canadienne de
 phytotechnie v. 71 (2): p. 525-526; 1991 Apr.  Includes
 references.
 
 Language:  English
 
 Descriptors: Ontario; Glycine max; Cultivars; Protein content;
 Tofu; Disease resistance; Phytophthora megasperma; Herbicide
 resistance; Metribuzin
 
 
 140                                    NAL Call. No.: S544.N6
 Herbicide mode of action and injury symptoms.
 Gunsolus, J.L.; Curran, W.S.
 East Lansing, Mich. : The Service; 1992.
 North Central regional extension publication, Cooperative
 Extension Service v.): 17 p.; 1992.
 
 Language:  English
 
 Descriptors: Herbicides; Mode of action; Application methods;
 Herbicide resistant weeds; Phototoxicity; Injuries; Symptoms
 
 
 141                            NAL Call. No.: S494.5.B563A382
 Herbicide resistance.
 Howard, J.; Baszczynski, C.
 Milan, Italy : Teknoscienze; 1992 Sep.
 Agrofoodindustry hi-tech v. 3 (5): p. 3-6; 1992 Sep.  Includes
 references.
 
 Language:  English
 
 Descriptors: Crops; Herbicide resistance; Biotechnology; Uses;
 Applications
 
 
 142                                    NAL Call. No.: S79.E37
 Herbicide resistance confirmed in johnsongrass biotypes.
 Barrentine, W.L.; Snipes, C.E.; Smeda, R.J.
 Mississippi State, Miss. : The Station; 1992 Aug.
 Research report - Mississippi Agricultural and Forestry
 Experiment Station v. 17 (5): 5 p.; 1992 Aug.  Includes
 references.
 
 Language:  English
 
 Descriptors: Mississippi; Sorghum halepense; Herbicide
 resistant weeds; Biotypes; Herbicides; Weed control; Trails
 
 
 143                          NAL Call. No.: S397.M57 no.93/10
 Herbicide resistance coordination and communication in Western
 Australia. Martin, R. J.
 Western Australia : Dept. of Agriculture,; 1993.
 17 p. : ill., map ; 30 cm. (Miscellaneous publication (Western
 Australia. Dept. of Agriculture) ; no. 93/10.).  Cover title. 
 March 17, 1993.  Agdex 640.
 
 Language:  English
 
 
 144                                  NAL Call. No.: 442.8 Z34
 Herbicide resistance due to amplification of a mutant
 acetohydroxyacid synthase gene.
 Harms, C.T.; Armour, S.L.; DiMaio, J.J.; Middlesteadt, L.A.;
 Murray, D.; Negrotto, D.V.; Thompson-Taylor, H.; Weymann, K.;
 Montoya, A.L.; Shillito, R.D.; Jen, G.C.
 Berlin, W. Ger. : Springer International; 1992 Jun.
 M G G : Molecular and general genetics v. 233 (3): p. 427-435;
 1992 Jun. Includes references.
 
 Language:  English
 
 Descriptors: Nicotiana tabacum; Amplification; Structural
 genes; Multiple genes; Oxo-acid-lyases; Herbicide resistance;
 Sulfonylurea herbicides; Imazaquin; In vitro selection; Enzyme
 activity; Mutants; Mutations; Genetic transformation;
 Transgenics; Protoplasts; Cell suspensions
 
 Abstract:  We have selected a tobacco cell line, SU-27D5, that
 is highly resistant to sulfonylurea and imidazolinone
 herbicides. This line was developed by selection first on a
 lethal concentration of cinosulfuron and then on increasing
 concentrations of primisulfuron, both sulfonylurea herbicides.
 SU-27D5 was tested against five sulfonylureas and one
 imidazolinone herbicide and was shown, in every case, to be
 two to three orders of magnitude more resistant than wild-type
 cells. The acetohydroxyacid synthase (AHAS) of SU-27D5 was 50-
 to 780-fold less sensitive than that of wild-type cells to
 herbicide inhibition. The specific activity of AHAS in the
 SU-27D5 cell lysate was 6 to 7 times greater than that in
 wild-type cells. Using Southern analysis, we showed that cell
 line SU-27D5 had amplified its SuRB AHAS gene about 20-fold
 while maintaining a normal diploid complement of the SuRA AHAS
 gene. Genomic clones of both AHAS genes were isolated and used
 to transform wild-type tobacco protoplasts. SuRB clones gave
 rise to herbicide-resistant transformants, whereas SuRA clones
 did not. DNA sequencing showed that all SuRB clones contained
 a point mutation at nucleotide 588 that converted amino acid
 196 of AHAS from proline to serine. In contrast, no mutations
 were found in the SuRA clones. The stability of SuRB gene
 amplification was variable in the absence of selection. In one
 experiment, the withdrawal of selection reduced the copy
 number of the amplified SuRB gene to the normal level within
 30 days. In another experiment, amplification remained stable
 after extended cultivation on herbicide-free medium. This is
 the first report of amplification of a mutant herbicide target
 gene that resulted in broad and strong herbicide resistance.
 
 
 145                                   NAL Call. No.: 450 P692
 Herbicide resistance in Datura innoxia. Kinetic
 characterization of acetolactate synthase from wild-type and
 sulfonylurea-resistant cell variants. Rathinasabapathi, B.;
 King, J.
 Rockville, Md. : American Society of Plant Physiologists; 1991
 May. Plant physiology v. 96 (1): p. 255-261; 1991 May. 
 Includes references.
 
 Language:  English
 
 Descriptors: Datura fastuosa; Cell cultures; Mutants;
 Sulfonylurea herbicides; Herbicide resistance; Imidazolinone
 herbicides; Ligases; Genetic variation; Cross resistance;
 Binding site; Amino acids; Biosynthesis
 
 Abstract:  Acetolactate synthase (ALS, EC 4.1.3.18), the first
 enzyme in the biosynthesis of branched-chain amino acids, was
 isolated from wild-type and sulfonylurea-resistant Datura
 innoxia cell variants and characterized. Apparent Km values of
 the ALS for pyruvate from three sulfonylurea-resistant
 variants (CSR2, CSR6, and CSR10) were manyfold greater than
 that of the wild type. The inhibition of wild-type and
 herbicide-resistant ALS activity by chlorsulfuron (CS), a
 sulfonylurea herbicide, and L-leucine (L-Leu), one of the
 feedback inhibitors of the enzyme, was examined. ALS from two
 CS-resistant variants exhibited severalfold greater resistance
 to CS than did the wild-type enzyme. Inhibition of ALS by L-
 Leu fitted a partially competitive pattern most closely. It is
 proposed that the herbicide resistance mutation accentuated
 the partial inhibition characteristics of ALS by L-Leu. ALS
 from one of the two CS-resistant variants (CSR6) had a Ki for
 L-Leu an order of magnitude greater than that of the wild-type
 enzyme. The alterations in kinetic properties observed in the
 ALS from sulfonylurea-resistant variants are discussed in
 relation to the possible evolutionary significance of the
 herbicide binding site of this enzyme, the physiological
 effects of such biochemical alterations, and their practical
 utility in genetic studies.
 
 
 146                                  NAL Call. No.: SB951.P49
 Herbicide resistance in Setaria viridis conferred by a less
 sensitive form of acetyl coenzyme A carboxylase.
 Marles, M.A.S.; Devine, M.D.; Hall, J.C.
 Orlando, Fla. : Academic Press; 1993 May.
 Pesticide biochemistry and physiology v. 46 (1): p. 7-14; 1993
 May.  Includes references.
 
 Language:  English
 
 Descriptors: Manitoba; Setaria viridis; Biotypes; Herbicide
 resistance; Susceptibility; Aryloxyphenoxypropionic
 herbicides; Cyclohexene oxime herbicides; Mode of action;
 Uptake; Metabolism; Acetyl-coa carboxylase; Enzyme activity;
 Inhibition
 
 Abstract:  The mechanism of resistance was investigated in a
 biotype of Setaria viridis resistant to
 aryloxyphenoxypropanoate and cyclohexanedione herbicides.
 Uptake of fenoxaprop-ethyl and diclofop-methyl was equal in
 the resistant and susceptible biotypes. In addition,
 metabolism of these two herbicides was similar in the
 resistant and susceptible biotypes, indicating that resistance
 is not based on altered herbicide metabolism. Fenoxaprop,
 diclofop, quizalofop, clethodim, sethoxydim, and tralkoxydim
 inhibited acetyl-coenzyme A carboxylase (ACCase) extracted
 from the susceptible biotype, with I(50) values ranging from
 0.078 to 1.7 micromolar. ACCase from the resistant biotype was
 much less sensitive to all herbicides, with I(50) values 31 to
 60 times higher than for the susceptible biotype. These
 results indicate that herbicide resistance in this S. viridis
 biotype is conferred by an altered form of ACCase that is much
 less sensitive to a wide range of aryloxyphenoxypropanoate and
 cyclohexanedione herbicides.
 
 
 147                          NAL Call. No.: SB951.4.H443 1991
 Herbicide resistance in weeds and crops.
 Caseley, J. C.; Cussans, G. W.; Atkin, R. K.
 Long Ashton International Symposium 11th : 1989.
 Oxford ; Boston : Butterworth-Heinemann,; 1991.
 xii, 513 p. : ill. ; 24 cm.  "Papers and poster abstracts
 presented at the Eleventh Long Ashton International Symposium
 in September 1989"--Pref. Includes bibliographical references
 and index.
 
 Language:  English
 
 Descriptors: Herbicide resistance; Herbicide-resistant crops
 
 
 148                                  NAL Call. No.: QH540.A55
 Herbicide resistance in weedy plants: physiology and
 population biology. Warwick, S.I.
 Palo Alto, Calif. : Annual Reviews, Inc; 1991.
 Annual review of ecology and systematics v. 22: p. 95-114;
 1991.  Literature review.  Includes references.
 
 Language:  English
 
 Descriptors: Weeds; Herbicide resistant weeds; Herbicide
 resistance; Gene flow; Genetic variation; Selection pressure;
 Natural selection; Triazines; Metabolic detoxification; Plant
 ecology; Reviews
 
 
 149                              NAL Call. No.: 275.29 M68Ext
 Herbicide resistance: prevention and detection.
 Byrd, J.D. Jr; Barrentine, W.L.; Shaw, D.R.
 State College, Miss. : Cooperative Extension Service,
 Mississippi State University; 1993 Sep.
 Publication / (1907): 4 p.; 1993 Sep.
 
 Language:  English
 
 Descriptors: Mississippi; Cabt; Crops; Weed control;
 Herbicides; Herbicide resistance; Susceptibility; Mode of
 action
 
 
 150                            NAL Call. No.: SB950.9.C44 v.7
 Herbicide resistance--brassinosteroids, gibberellins, plant
 growth regulators. Adam, G.
 Berlin ; New York : Springer-Verlag,; 1991.
 176 p. : ill. ; 24 cm. (Chemistry of plant protection ; 7). 
 Includes bibliographical references and index.
 
 Language:  English
 
 Descriptors: Herbicide resistance; Gibberellins; Brassinolide;
 Plant regulators
 
 
 151                                  NAL Call. No.: aZ5071.N3
 Herbicide resistance--January 1989-March 1991.
 Schneider, K.
 Beltsville, Md. : The Library; 1991 May.
 Quick bibliography series - U.S. Department of Agriculture,
 National Agricultural Library (U.S.). (91-104): 41 p.; 1991
 May.  Updates QB 86-51. Bibliography.
 
 Language:  English
 
 Descriptors: Herbicide resistance; Bibliographies
 
 
 152                                   NAL Call. No.: QH442.B5
 Herbicide resistant fertile transgenic wheat plants obtained
 by microprojectile bombardment of regenerable embryogenic
 callus. Vasil, V.; Castillo, A.M.; Fromm, M.E.; Vasil, I.K.
 New York, N.Y. : Nature Publishing Company; 1992 Jun.
 Bio/technology v. 10 (6): p. 662-674; 1992 Jun.  Includes
 references.
 
 Language:  English
 
 Descriptors: Triticum aestivum; Genetic transformation; Direct 
 DNAuptake; Transgenics; Gene transfer; Structural genes;
 Acyltransferases; Plasmids; Herbicide resistance; Glufosinate;
 Callus; Regenerative ability; Embryogenesis; Reporter genes
 
 
 153                                  NAL Call. No.: 79.9 C122
 Herbicide resistant in weeds current status and future
 perspectives. Saari, L.L.
 Fremont, Calif. : California Weed Conference; 1991.
 Proceedings - California Weed Conference (43rd): p. 37-40;
 1991.  Meeting held January 21-23, 1991, Santa Barbara,
 California.  Includes references.
 
 Language:  English
 
 Descriptors: Herbicide resistant weeds; Weed control; Chemical
 control
 
 
 154                                  NAL Call. No.: 443.8 H42
 Herbicide response polymorphism in wild populations of emmer
 wheat. Snape, J.W.; Nevo, E.; Parker, B.B.; Leckie, D.;
 Morgunov, A. Oxford : Blackwell Scientific Publications; 1991
 Apr.
 Heredity v. 66 (pt.2): p. 251-257; 1991 Apr.  Includes
 references.
 
 Language:  English
 
 Descriptors: Israel; Triticum dicoccoides; Genes; Genetic
 resources; Evolution; Herbicide resistance; Difenzoquat;
 Metoxuron; Genetic polymorphism; Geographical distribution;
 Wild plants
 
 Abstract:  The responses of wild populations of emmer wheat
 (Triticum dicoccoides), from different ecogeographical areas
 of Israel, to three herbicides, difenzoquat, chlortoluron and
 metoxuron, commonly used on cultivated wheats, were studied.
 Although cultivated wheats are polymorphic for a response to
 difenzoquat, all families of all populations of the wild
 species were resistant. The species was, however, polymorphic
 for response to both chlortoluron and metoxuron. In addition,
 there appeared to be differentiation between populations in
 the frequencies of resistant and susceptible morphs for these
 herbicides. There was also a close correspondence between the
 responses of individual families to chlortoluron and
 metoxuron, which suggests a common genetic control. The
 implications of these findings for understanding the evolution
 of herbicide resistance, and for developing strategies for
 breeding for resistance in the cultivated species are
 discussed.
 
 
 155                                   NAL Call. No.: 442.8 Z8
 Herbicide response polymorphisms in wild emmer wheat:
 ecological and isozyme correlations.
 Nevo, E.; Snape, J.W.; Lavie, B.; Beiles, A.
 Berlin, W. Ger. : Springer International; 1992.
 Theoretical and applied genetics v. 84 (1/2): p. 209-216;
 1992.  Includes references.
 
 Language:  English
 
 Descriptors: Israel; Triticum dicoccoides; Genetic resources;
 Herbicide resistance; Polymorphism; Metoxuron; Chlorotoluron;
 Phenotypes; Marker genes; Genotypes; Isoenzymes; Alloenzymes;
 Enzyme polymorphism; Genetic markers; Ecotypes; Geographical
 distribution; Gene frequency; Photosynthesis; Plant ecology
 
 Abstract:  We demonstrate that the scores and frequencies of
 chlortoluron (CT) and metoxuron (MX) resistance and
 susceptible phenotypes of wild emmer wheat, Triticum
 dicoccoides, are correlated with ecological factors and
 allozyme markers. Some isozyme markers located on chromosome
 6B (e.g. Adh, Est-4 and Got), which also harbours the CT and
 MX resistance gene, provide good genetic markers for herbicide
 resistance breeding. Significant correlations between
 herbicide and photosynthetic characters suggest that the
 evolution of herbicide resistance polymorphisms may be related
 to the process of photosynthesis in nature and predated
 domestication of cultivated wheat.
 
 
 156                             NAL Call. No.: S494.5.B563N33
 Herbicide tolerance in crops. 1.
 Fehr, W.R.
 Ithaca, N.Y. : National Agricultural Biotechnology Council;
 1991. NABC report / (3): p. 179-198; 1991.  In the series
 analytic: Agricultural biotechnology at the crossroads:
 biological, social and institutional concerns.  Proceedings of
 the National Agricultural Biotechnology Council's third annual
 meeting, May 1991.  Includes references.
 
 Language:  English
 
 Descriptors: Herbicides; Tolerance; Biotechnology
 
 
 157                             NAL Call. No.: QK658.A54 1992
 Herbicide tolerance in maize--genetics and pollen selection.
 Gorla, M.S.; Ferrario, S.; Gianfranceschi, L.; Villa, M.
 New York : Springer-Verlag; 1992.
 Angiosperm pollen and ovules / E. Ottaviano ... [et al.,
 editors]. p. 364-369; 1992.  Includes references.
 
 Language:  English
 
 Descriptors: Maize; Plant breeding; Selective breeding;
 Genetic resistance; Herbicides
 
 
 158                                NAL Call. No.: SB610.2.B74
 Herbicide tolerance in winter oilseed rape.
 Lutman, P.J.W.; Dixon, F.L.
 Surrey : BCPC Registered Office; 1991.
 Brighton Crop Protection Conference-Weeds v. 1: p. 195-202;
 1991.  Includes references.
 
 Language:  English
 
 Descriptors: Brassica napus; Weed control; Metazachlor;
 Tolerance; Pyridate; Fluroxypyr
 
 
 159                                  NAL Call. No.: 79.9 W52R
 Herbicide tolerance of seedling grasses for erosion control in
 a spotted knapweed infested parkland.
 Lass, L.W.; Callihan, R.H.
 S.l. : The Society; 1991.
 Research progress report - Western Society of Weed Science. p.
 24-26; 1991. Meeting held March 12-14, 1991, Seattle,
 Washington.
 
 Language:  English
 
 Descriptors: Centaurea repens; Gramineae; Stand establishment;
 Weed control; Herbicides
 
 
 160                                    NAL Call. No.: SB1.J66
 Herbicide tolerance of selected ericaceous species.
 Skroch, W.A.; Warren, S.L.; Gallitano, L.B.
 Washington, D.C. : Horticultural Research Institute; 1991 Dec.
 Journal of environmental horticulture v. 9 (4): p. 196-198;
 1991 Dec. Includes references.
 
 Language:  English
 
 Descriptors: Ornamental woody plants; Kalmia latifolia;
 Leucothoe walteri; Oxydendrum arboreum; Rhododendron;
 Rhododendron catawbiense; Rhododendron obtusum; Herbicide
 resistance; Herbicide mixtures; Phytotoxicity
 
 
 161                               NAL Call. No.: SB950.2.I3I4
 Herbicide tolerant crops.
 Graham, J.
 Urbana, Ill. : Cooperative Extension Service, Univ of Illinois
 at Urbana-Champaign; 1991.
 Illinois Agricultural Pesticides Conference summaries of
 presentations January 8, 9, 10, 1991, Urbana, Illinois / Univ
 of Illinois at Urbana-Champaign, Coop Ext Serv, in coop with
 the Illinois Natural History Survey. p. 167-169; 1991.
 "Proceedings of the 1991 Illinois Agricultural Pesticides
 Conference," January 8-10, 1991, Urbana, Illinois.
 
 Language:  English
 
 Descriptors: Crops; Herbicide resistance; Genetic engineering
 
 
 162                                  NAL Call. No.: SB951.P49
 Herbicide-insecticide interaction in maize: malathion inhibits
 cytochrome P450-dependent primisulfuron metabolism.
 Kreuz, K.; Fonne-Pfister, R.
 Orlando, Fla. : Academic Press; 1992 Jul.
 Pesticide biochemistry and physiology v. 43 (3): p. 232-240;
 1992 Jul. Includes references.
 
 Language:  English
 
 Descriptors: Zea mays; Herbicide resistance; Sulfonylurea
 herbicides; Interactions; Organophosphorus insecticides;
 Phytotoxicity; Antagonism; Malathion; Metabolism; Metabolic
 detoxification; Cytochrome p-450; Enzyme activity; Microsomes;
 Herbicide mixtures; Pharmacokinetics
 
 Abstract:  Tolerance of maize to sulfonylurea herbicides such
 as primisulfuron has recently been reported to be impaired by
 the use of some organophosphorus insecticides. In an effort to
 elucidate the mechanism of this interaction, the effect of the
 insecticide, malathion, on the metabolism of primisulfuron was
 studied in whole plants, in excised leaves, and in a
 microsomal in vitro system from maize. Foliar application of
 malathion to 7-day-old plants had no influence on leaf uptake
 and translocation of primisulfuron, but caused a decrease in
 the rate of herbicide metabolism. In excised leaves, malathion
 increased the metabolic half-life of primisulfuron. In
 microsomal preparations, malathion inhibited cytochrome P450-
 dependent primisulfuron phenyl- and pyrimidinering
 hydroxylation. Loss of primisulfuron phenyl-ring hydroxylase
 activity was time-dependent, saturable with respect to
 malathion concentration, and attenuated in the absence of
 NADPH. The kinetic data suggest a mechanism-based cytochrome
 P450 inactivation by malathion. The oxoanalogue of malathion,
 malaoxon, did not influence the metabolic half-life of
 primisulfuron in excised leaves and was a poor inhibitor of
 microsomal primisulfuron hydroxylation. Neither insecticide
 had any effect in vitro on total microsomal cytochrome P450
 content. From the present results it may be concluded that
 malathion affects primisulfuron tolerance of maize due to the
 inhibition of cytochrome P450 monooxygenases involved in
 herbicide metabolism.
 
 
 163                                  NAL Call. No.: 381 J825N
 Herbicide-resistant crops focus of biotechnology debate.
 Baum, R.M.
 Washington, D.C. : American Chemical Society; 1993 Mar08.
 Chemical and engineering news v. 71 (10): p. 38-41; 1993
 Mar08.
 
 Language:  English
 
 Descriptors: U.S.A.; Herbicide resistance; Crops; Genetic
 engineering; Usda; Public opinion
 
 
 164                                  NAL Call. No.: QK710.P62
 Herbicide-resistant Indica rice plants from IRRI breeding line
 IR72 after PEG-mediated transformation of protoplasts.
 Datta, S.K.; Datta, K.; Soltanifar, N.; Donn, G.; Potrykus, I.
 Dordrecht : Kluwer Academic Publishers; 1992 Nov.
 Plant molecular biology : an international journal on
 molecular biology, biochemistry and genetic engineering v. 20
 (4): p. 619-629; 1992 Nov. Includes references.
 
 Language:  English
 
 Descriptors: Oryza sativa; Genetic transformation;
 Protoplasts; Direct DNAuptake; Polyethylene glycol; Gene
 transfer; Transgenics; Phosphotransferases; Drug resistance;
 Hygromycin b; Acyltransferases; Herbicide resistance;
 Glufosinate; Regenerative ability; Enzyme activity
 
 Abstract:  The commercially important Indica rice cultivar
 Oryza sativa cv. IR72 has been transformed using direct gene
 transfer to protoplasts. PEG-mediated transformation was done
 with two plasmid constructs containing either a CaMV 35S
 promoter/HPH chimaeric gene conferring resistance to
 hygromycin (Hg) or a CaMV 35S promoter/BAR chimaeric gene
 conferring resistance to a commercial herbicide (Basta)
 containing phosphinothricin (PPT). We have obtained so far 92
 Hg(r) and 170 PPT(r) IR72 plants from protoplasts through
 selection. 31 Hg(r) and 70 PPT(r) plants are being grown in
 the greenhouse to maturity. Data from Southern analysis and
 enzyme assays proved that the transgene was stably integrated
 into the host genome and expressed. Transgenic plants showed
 complete resistance to high doses of the commercial
 formulations of PPT.
 
 
 165                                  NAL Call. No.: 450 P5622
 Herbicide-resistant lines of microalgae: growth and fatty acid
 composition. Cohen, Z.; Reungjitchachawali, M.; Siangdung, W.;
 Tanticharoen, M.; Heimer, Y.M.
 Oxford ; New York : Pergamon Press, 1961-; 1993 Nov.
 Phytochemistry v. 34 (4): p. 973-978; 1993 Nov.  Includes
 references.
 
 Language:  English
 
 Descriptors: Rhodophyta; Spirulina; Algae; Eicosapentaenoic
 acid; Fatty acids; Growth; Herbicide resistance; Lines;
 Linolenic acid
 
 Abstract:  Cell lines of Spirulina platensis and Porphyridium
 cruentum resistant to growth inhibition by the herbicide SAN
 9785 had a significantly higher growth rate than their
 respective wild-type strains. These lines were also shown to
 overproduce gamma-linolenic acid (GLA) and eicosapentaenoic
 acid (EPA), respectively, in the presence and absence of the
 inhibitor, as compared with wild-type cultures under similar
 conditions. The effect was most conspicuous in polar lipids.
 Thus, the proportion of GLA in the galactolipid (GL) fraction
 of the SAN 9785-resistant strain of S. platensis, SRS-1,
 increased in the absence of the inhibitor from 33.3% in the
 wild-type to 39.0%. Similarly, the proportion of EPA in the GL
 fraction of the resistant strain of P. cruentum, SRP,
 increased in the presence of the inhibitor from 29.1 to 45.4%.
 
 
 166                                    NAL Call. No.: 10 J822
 Herbicide-resistant weeds: a worldwide perspective.
 Moss, S.R.; Rubin, B.
 Cambridge : Cambridge University Press; 1993 Apr.
 The Journal of agricultural science v. 120 (pt.2): p. 141-148;
 1993 Apr. Literature review.  Includes references.
 
 Language:  English
 
 Descriptors: Herbicide resistant weeds; Incidence; Literature
 reviews; Models; Resistance mechanisms; Herbicides
 
 
 167                               NAL Call. No.: 275.29 W27Pn
 Herbicide-resistant weeds and their management.
 Mallory-Smith, C.; Thill, D.; Morishita, D.
 Corvallis, Or. : Washington, Oregon, and Idaho State
 Universities, Cooperative Extension Service; 1993.
 PNW [1993?] (437): 4 p.; 1993.
 
 Language:  English
 
 Descriptors: Herbicide resistant weeds; Biotypes; Weed
 control; Herbicides
 
 
 168                                   NAL Call. No.: 79.8 W41
 Herbicides that inhibit acetohydroxyacid synthase.
 Stidham, M.A.
 Champaign, Ill. : Weed Science Society of America; 1991 Jul.
 Weed science v. 39 (3): p. 428-434; 1991 Jul.  Paper presented
 at the "Symposium on Herbicide Mechanism of Action," February
 7, 1990, Montreal, Canada.  Includes references.
 
 Language:  English
 
 Descriptors: Sulfonylurea herbicides; Imidazolinone
 herbicides; Mode of action; Enzyme inhibitors; Ligases;
 Herbicidal properties; Protein synthesis inhibitors; Structure
 activity relationships; Herbicide resistance; Zea mays;
 Resistance mechanisms
 
 Abstract:  Acetohydroxyacid synthase was discovered as the
 site of action of imidazolinone and sulfonylurea herbicides
 over 6 yr ago. In recent years, advances have been made in the
 understanding of this enzyme as a herbicide target site.
 Derivatives of both imidazolinones and sulfonylureas have
 yielded new herbicide chemistry. All of the herbicides display
 unusual "slow-binding" behavior with the enzyme, and this
 behavior may help explain efficacy of the herbicides.
 Resistance to these herbicides has been developed through a
 number of different procedures, and the mechanism of
 resistance is through changes in sensitivity of the enzyme to
 the herbicides. The changes are either selective to only one
 class of chemistry, or broad to a number of classes of
 chemistry. These data support the idea that binding sites for
 the herbicides on the enzyme are only partially overlapping.
 Progress in purification of AHAS from corn includes discovery
 of the existence of the enzyme in monomer and oligomer
 aggregation states. The interaction of the enzyme with the
 herbicides is affected by enzyme aggregation state.
 
 
 169                                     NAL Call. No.: A00109
 Herbicide-tolerant crops dominate testing in the
 industrialized world. Washington, DC : National Biotechnology
 Policy Center of the National Wildlife Federation; 1993 May.
 The gene exchange v. 4 (1): p. 3; 1993 May.
 
 Language:  English
 
 Descriptors: Herbicide resistance; Field tests
 
 
 170                                  NAL Call. No.: 442.8 Z34
 High frequency, heat treatment-induced inactivation of the
 phosphinothricin resistance gene in transgenic single cell
 suspension cultures of Medicago sativa.
 Walter, C.; Broer, I.; Hillemann, D.; Puhler, A.
 Berlin, W. Ger. : Springer International; 1992 Nov.
 M G G : Molecular and general genetics v. 235 (2/3): p.
 189-196; 1992 Nov. Includes references.
 
 Language:  English
 
 Descriptors: Medicago sativa; Genetic transformation;
 Transgenics; Structural genes; Acyltransferases; Glufosinate;
 Herbicide resistance; Gene expression; Cell suspensions;
 Genetic regulation; Heat; Callus; Regenerative ability; Enzyme
 activity
 
 Abstract:  One descendant of the Medicago sativa Ra-3
 transformant T304 was analysed with respect to the somatic
 stability of the synthetic phosphinothricin-N-
 acetyltransferase (pat) gene which was used as a selective
 marker and was under the control of the 5'/3' expression
 signals of the cauliflower mosaic virus (CaMV) gene VI. In
 order to quantify gene instability, we developed a system for
 culturing and regenerating individual cells. Single cell
 suspension cultures derived from T304 and the ancestral non-
 transgenic M. sativa cultivar Ra-3, were established. The
 cells were regenerated into monoclonal calli. In transgenic
 calli, the phosphinothricin (Pt)-resistance phenotype was
 retained after more than 2 months of non-selective growth. In
 contrast, up to 12% of the suspension culture cells grown
 under non-selective conditions and at constant temperature (25
 degrees C) lost the herbicide-resistance phenotype within 150
 days. Surprisingly, a heat treatment (37 degrees C), lasting
 for 10 days, during the culture period resulted in an almost
 complete (95%) loss of the Pt resistance of the suspension
 culture cells. However, the frequency of cell division was
 identical in cultures grown under normal and heat treatment
 conditions. A biochemical test revealed that no
 phosphinothricin-N-acetyltransferase activity was present in
 heat treated, Pt-sensitive cells. The resistance level of the
 Pt-sensitive transgenic cells was equivalent to that of the
 wild-type cells. A PCR analysis confirmed the presence of the
 pat gene in heat treated, Pt-sensitive cells. From these
 results it is concluded that the Pt resistance gene was heat-
 inactivated at a high frequency in the M. sativa suspension
 cultures.
 
 
 171                                  NAL Call. No.: SB610.W39
 History of herbicide--tolerant crops, methods of development
 and current state of the art--emphasis on glyphosate
 tolerance.
 Kishore, G.M.; Padgette, S.R.; Fraley, R.T.
 Champaign, Ill. : The Society; 1992 Jul.
 Weed technology : a journal of the Weed Science Society of
 America v. 6 (3): p. 626-634; 1992 Jul.  Paper presented at
 the Symposium, "Development of Herbicide-Resistant Crop
 Cultivars", Weed Science Society of America, February 6, 1991,
 Louisville, Kentucky.  Literature review.  Includes
 references.
 
 Language:  English
 
 Descriptors: Transgenic plants; Crops; Herbicide resistance;
 Glyphosate; Weed control; Chemical control; Gene transfer;
 Biotechnology; Research; Literature reviews
 
 
 172                                  NAL Call. No.: SB610.W39
 History of identification of herbicide-resistant weeds.
 Holt, J.S.
 Champaign, Ill. : The Society; 1992 Jul.
 Weed technology : a journal of the Weed Science Society of
 America. p. 615-620; 1992 Jul.  Paper presented at the
 Symposium, "Development of Herbicide-Resistant Crop
 Cultivars", Weed Science Society of America, February 6, 1991,
 Louisville, Kentucky.  Includes references.
 
 Language:  English
 
 Descriptors: Herbicide resistant weeds; Herbicide resistance;
 Detection; Biotypes; Cross resistance; Resistance mechanisms;
 Weed control; Chemical control; History
 
 
 173                                     NAL Call. No.: SB1.H6
 ID-BR1: sulfonylurea herbicide-resistant lettuce germplasm.
 Mallory-Smith, C.; Thill, D.C.; Dial, M.J.
 Alexandria, Va. : American Society for Horticultural Science;
 1993 Jan. HortScience v. 28 (1): p. 63-64; 1993 Jan.  Includes
 references.
 
 Language:  English
 
 Descriptors: Lactuca sativa; Lactuca serriola; Germplasm;
 Herbicide resistance; Sulfonylurea herbicides; Plant breeding
 
 
 174                                  NAL Call. No.: 64.8 C883
 Identification and inheritance of metribuzin tolerance in wild
 soybean. Kilen, T.C.; He, G.
 Madison, Wis. : Crop Science Society of America; 1992 May.
 Crop science v. 32 (3): p. 684-685; 1992 May.  Includes
 references.
 
 Language:  English
 
 Descriptors: Glycine max; Wild plants; Metribuzin; Herbicide
 resistance; Germplasm; Diversity; Genetic regulation; Alleles;
 Loci; Gene location; Inheritance; Plant breeding
 
 Abstract:  An economically important agronomic trait that has
 not been evaluated extensively in the wild soy (Glycine soja
 Sieb. & Zucc.) is tolerance to herbicides. Identification and
 genetic characterization of tolerance to a widely used
 herbicide, metribuzin
 [4-amino-6-(1,1-dimethylethyl)-3-
 (methylthio)-1,2,4.triazin-5(4H)-one], in G. soja may help
 provide greater diversity in the gene pool for this trait.
 This study was conducted to identify tolerance to metribuzin
 in the wild soybean and to determine the genetic control of
 the trait. Crosses were made from metribuzin-tolerant G. soja
 selections and metribuzin-sensitive selections of G. max (L.)
 Merr. The F1, F2, and F3 populations from these crosses were
 grown hydroponically, and evaluated for reaction to a
 concentration of 125 microgram L-1 metribuzin. The F1 plants
 were tolerant, the F2 population segregated in a 3 tolerant: 1
 sensitive ratio, and the F2 population segregated in 1
 tolerant: 2 segregating: 1 sensitive ratio, suggesting a
 single dominant gene controlling tolerance. The F2 populations
 from crosses between metribuzin-tolerant G. soja accessions
 and the metribuzin-tolerant cultivar Tracy-M were all
 tolerant. This indicates that tolerance to metribuzin in these
 two wild soybean accessions is controlled by alleles at the
 same locus as the Hm gene in Tracy-M. Therefore, the
 metribuzin tolerance in the wild soybean is probably the same
 as that found in most of the cultivated soybean accessions and
 in most commercial cultivars. The significance of identifying
 tolerance to a currently used herbicide in the wild soybean is
 the suggestion that other useful traits needed in modern
 agriculture may be found in this primitive gene pool.
 
 
 175                                  NAL Call. No.: SB610.W39
 Imazaquin absorption, translocation, and metabolism in flue-
 cured tobacco. Walls, F.R. Jr; Corbin, F.T.; Collins, W.K.;
 Worsham, A.D.; Bradley, J.R. Jr Champaign, Ill. : The Weed
 Science Society of America; 1993 Apr. Weed technology : a
 journal of the Weed Science Society of America v. 7 (2): p.
 370-375; 1993 Apr.  Includes references.
 
 Language:  English
 
 Descriptors: North Carolina; Cabt; Nicotiana tabacum;
 Herbicide resistance; Imazaquin; Leaves; Absorption;
 Translocation; Metabolism; Seedling stage; Source sink
 relations; Roots; Shoots; Foliar application; Soil treatment;
 Weed control; Chemical control; Phytotoxicity
 
 
 176                                  NAL Call. No.: SB951.P49
 Increased detoxification is a mechanism of simazine resistance
 in Lolium rigidum.
 Burnet, M.W.M.; Loveys, B.R.; Holtum, J.A.M.; Powles, S.B.
 Orlando, Fla. : Academic Press; 1993 Jul.
 Pesticide biochemistry and physiology v. 46 (3): p. 207-218;
 1993 Jul. Includes references.
 
 Language:  English
 
 Descriptors: Lolium rigidum; Biotypes; Weeds; Herbicide
 resistance; Susceptibility; Simazine; Resistance mechanisms;
 Metabolic detoxification; Metabolism; Metabolites; Metabolic
 inhibitors; Thylakoids; Oxygen; Uptake; Translocation;
 Heritability
 
 Abstract:  Biotypes of Lolium rigidum Gaud. (annual ryegrass)
 resistant to the triazine herbicides were studied to determine
 the mechanism of resistance. The resistant biotypes have
 different histories of exposure to the herbicide atrazine but
 both exhibit greater resistance to the structurally similar
 triazine herbicide simazine. Simazine resistance is not due to
 a change at the target site, as a similar concentration of
 simazine is required for a 50% reduction in electron transport
 by thylakoids isolated from resistant and susceptible
 biotypes. Uptake of simazine from nutrient solution and
 distribution of simazine between the roots and the shoots are
 similar in resistant and susceptible biotypes. Following
 application to the roots, more than 95% of the absorbed
 simazine was translocated to the shoots in both resistant and
 susceptible biotypes. Resistant biotypes metabolized
 [14C)simazine at a greater rate than susceptible plants when
 simazine was supplied as either a 12-hr pulse or continuously
 over 7 days. Over a 7-day exposure to simazine (3 micromolar),
 susceptible plants accumulated simazine in their shoot
 tissues, whereas resistant plants maintained a low and stable
 amount of simazine by metabolizing simazine at a greater rate
 than the susceptible plants. The primary products of simazine
 metabolism were tentatively identified as N-de-ethyl
 derivatives. Up to eight other minor metabolites were also
 observed. The cytochrome P450 inhibitor 1-aminobenzotriazole
 (ABT) (70 micromolar) in combination with simazine (3
 micromolar) for 7 days caused a greater reduction in dry
 weight of resistant plants than simazine applied alone. ABT
 inhibited the metabolism of simazine by all biotypes whether
 applied as a 12-hr pulse or over a 7-day period. In the
 presence of ABT the amount of simazine in the resistant shoot
 tissue was similar to that in susceptible plants treated with
 simazine alone. The nature of the metabolites and the
 inhibition of metabolism by ABT suggest the involvement of
 oxidative enzymes in the mechanism of resistance to simazine.
 
 
 177                                   NAL Call. No.: 500 N21P
 Increased resistance to oxidation stress in transgenic plants
 that overexpress chloroplastic Cu/Zn superoxide dismutase.
 Gupta, A.S.; Heinen, J.L.; Holaday, A.S.; Burke, J.J.; Allen,
 R.D. Washington, D.C. : The Academy; 1993 Feb15.
 Proceedings of the National Academy of Sciences of the United
 States of America v. 90 (4): p. 1629-1633; 1993 Feb15. 
 Includes references.
 
 Language:  English
 
 Descriptors: Nicotiana tabacum; Transgenics; Chloroplasts;
 Gene expression; Genetic code; Oxidation; Photoinhibition;
 Stress; Superoxide dismutase; Herbicide resistance
 
 Abstract:  Transgenic tobacco plants that express a chimeric
 gene that encodes chloroplast-localized Cu/Zn superoxide
 dismutase (SOD) from pea have been developed. To investigate
 whether increased expression of chloroplast-targeted SOD could
 after the resistance of photosynthesis to environmental
 stress, these plants were subjected to chilling temperatures
 and moderate (500 micromole of quanta per m2 per s) or high
 (1500 micromole of quanta per m2 per s) light intensity.
 During exposure to moderate stress, transgenic SOD plants
 retained rates of photosynthesis approximately 20% higher than
 untransformed tobacco plants, implicating active oxygen
 species in the reduction of photosynthesis during chilling.
 Unlike untransformed plants, transgenic SOD plants were
 capable of maintaining nearly 90% of their photosynthetic
 capacity (determined by their photosynthetic rates at 25
 degrees C) following exposure to chilling at high light
 intensity for 4 hr. These plants also showed reduced levels of
 light-mediated cellular damage from the superoxide-generating
 herbicide methyl viologen. These results demonstrate that SOD
 is a critical component of the active-oxygen-scavenging system
 of plant chloroplasts and indicate that modification of SOD
 expression in transgenic plants can improve plant stress
 tolerance.
 
 
 178                                   NAL Call. No.: 450 P693
 Increased sterol biosynthesis in tobacco calli resistant to a
 triazole herbicide which inhibits demethylation of 14alpha-
 methyl sterols. Schaller, H.; Maillot-Vernier, P.; Belliard,
 G.; Benveniste, P. Berlin : Springer-Verlag; 1992.
 Planta v. 187 (3): p. 315-321; 1992.  Includes references.
 
 Language:  English
 
 Descriptors: Nicotiana tabacum; Callus; Sterols; Biosynthesis;
 Triazole herbicides; Herbicide resistance; Biochemical
 pathways; Methylation
 
 Abstract:  The gamma-keto triazole derivative
 4,4-dimethyl-1-(2-methoxyphenyl)-1-(1,2,4-triazol-1-yl)-1-
 penten-3-one is toxic to Nicotiana tabacum L. cv. Xanthi
 plants or cell cultures. Analysis of the sterol composition of
 treated wild-type plant material demonstrates that this
 herbicide is an inhibitor of the C-14 alpha-methyl
 demethylation process in sterol biosynthesis. Selection
 experiments, consisting of screening large populations of
 microcalli derived from UV-mutagenized tobacco protoplasts for
 resistance to a lethal dose (1 mg.l-1) of the gamma-keto
 triazole, have resulted in the recovery of two groups of
 resistant calli. In the first group, selected calli show a
 sterol composition in the absence or presence of the inhibitor
 very similar to that of wild-type sensitive calli, whereas in
 the second group the main feature of the selected calli is a
 new sterol profile. These calli present an overproduction of
 sterols with a concomitant esterification of overproduced
 metabolites, just as it was demonstrated for calli previously
 selected in our laboratory for resistance to LAB 170250F, a
 triazole fungicide (Maillot-Vernier et al., 1991, Mol. Gen.
 Genet. 231, 33-40).
 
 
 179                                  NAL Call. No.: TA166.T72
 Indiscriminate use of selectable markers--sowing wild oats?.
 Gressel, J.
 New York, N.Y. : Elsevier Science Publishing Co; 1992 Nov.
 Trends in biotechnology v. 10 (11): p. 382; 1992 Nov. 
 Includes references.
 
 Language:  English
 
 Descriptors: Avena fatua; Genetic markers; Marker genes;
 Herbicide resistance; Glufosinate; Gene transfer; Avena
 sativa; Transgenics; Biotechnology
 
 
 180                                  NAL Call. No.: SB951.P49
 Induced microsomal oxidation of diclofop, triasulfuron,
 chlorsulfuron, and linuron in wheat.
 Frear, D.S.; Swanson, H.R.; Thalacker, F.W.
 Orlando, Fla. : Academic Press; 1991 Nov.
 Pesticide biochemistry and physiology v. 41 (3): p. 274-287;
 1991 Nov. Includes references.
 
 Language:  English
 
 Descriptors: Triticum aestivum; Seedlings; Shoots; Metabolic
 detoxification; Diclofop; Chlorsulfuron; Triasulfuron;
 Linuron; Herbicide resistance; Phytotoxicity; Selectivity;
 Oxidation; Microsomes; Enzyme activity; Monophenol
 monooxygenase; Nadh dehydrogenase; Cytochrome p-450;
 Oxygenases; Characterization; Pharmacokinetics
 
 Abstract:  Microsomal fractions from shoot tissues of
 etiolated wheat seedlings catalyzed the oxidation of diclofop,
 chlorsulfuron, triasulfuron, chlortoluron, and linuron.
 Microsomal oxidation products of chlorsulfuron, triasulfuron,
 and linuron were isolated and identified by mass spectrometry
 and cochromatography with reference standards. Oxidation was
 dependent on NADPH and molecular oxygen and was inhibited by
 CO in the presence of oxygen. Triasulfuron hydroxylation was
 inhibited to varying degrees by other known inhibitors of
 cytochrome P-450 enzymes and by several different
 postemergence herbicides. Enzyme activity was increased 2- to
 3-fold by the removal of endogenous inhibitors and stimulated
 an additional 5- to 20-fold by the treatment of germinating
 seedlings with naphthalic anhydride, ethanol, or
 phenobarbital. In contrast to marked increases in
 monooxygenase activities following induction, microsomal
 cytochrome P-450 levels and NADPH cytochrome c reductase
 activities were not increased to a significant extent. Ethanol
 and phenobarbital were more effective than naphthalic
 anhydride as inducers of microsomal hydroxylase activity. The
 combined effect of naphthalic anhydride and ethanol as
 inducers of diclofop and triasulfuron hydroxylases was
 additive. Apparent Km values for triasulfuron, chlorsulfuron,
 and diclofop with constitutive and induced microsomal
 hydroxylases were compared. Differences in the response of
 herbicide monooxygenases to selected inhibitors, inducers, and
 substrates support the hypothesis that wheat microsomes
 contain a number of distinct cytochrome P-450-dependent
 monooxygenases with different substrate specificities and
 kinetic properties. These enzymes serve as important factors
 in the tolerance and selectivity of a broad spectrum of
 herbicides used in wheat production systems.
 
 
 181                             NAL Call. No.: SB349.D44 1992
 Induced plant cell modifications analysis of herbicide-
 resistant tomato cells possessing altered cell wall
 composition..  Induces plant cell wall modifications
 Delmer, Deborah P.; Lamport, D. T. A.
 United States-Israel Binational Agricultural Research and
 Development Fund Bet Dagan, Israel : BARD,; 1992.
 1 v. (various pagings) : ill. ; 29 cm.  Cover title: Induces
 plant cell wall modifications.  Final report.  Project no.
 IS-1386-87.  Includes bibliographical references.
 
 Language:  English
 
 Descriptors: Tomatoes; Plant cell walls
 
 
 182       NAL Call. No.: MdULD3231.M70d Bandaranayake, H.A.D.
 Induction, transformation and characterization of herbicide
 resistance in Nicotiana.
 Bandaranayake, Hema Anura Divale
 University of Maryland at College Park, Dept. of Botany
 1992; 1992.
 vii, 84 leaves : ill. ; 29 cm.  Thesis research directed by
 Dept. of Botany. Includes bibliographical references (leaves
 70-84).
 
 Language:  English
 
 Descriptors: Tobacco; Plants, Effect of herbicides on
 
 
 183                                  NAL Call. No.: SB610.W39
 An industry perspective on herbicide-tolerant crops.
 Giaquinta, R.T.
 Champaign, Ill. : The Society; 1992 Jul.
 Weed technology : a journal of the Weed Science Society of
 America v. 6 (3): p. 653-656; 1992 Jul.  Paper presented at
 the Symposium, "Development of Herbicide-Resistant Crop
 Cultivars", Weed Science Society of America, February 6, 1991,
 Louisville, Kentucky.  Includes references.
 
 Language:  English
 
 Descriptors: Transgenic plants; Crops; Herbicide resistance;
 Biotechnology; Industry; Weed control
 
 
 184                                  NAL Call. No.: 79.8 W412
 Influence of light intensity on growth of triazine-resistant
 rapeseed (Brassica napus).
 Hart, J.J.; Radosevich, S.R.; Stemler, A.
 Oxford : Blackwell Scientific Publications; 1992 Oct.
 Weed research v. 32 (5): p. 349-356; 1992 Oct.  Includes
 references.
 
 Language:  English
 
 Descriptors: Brassica napus; Lines; Selection criteria;
 Herbicide resistance; Triazines; Crossing; Light intensity;
 Growth; Dry matter accumulation; Responses; Greenhouse
 culture; Growth chambers; Photosynthesis; Performance
 
 
 185                                   NAL Call. No.: 23 AU783
 Influence of rainfall and temperature on sensitivity of barley
 (Hordeum vulgare) to Chlorsulfuron.
 Lemerle, D.
 Melbourne : Commonwealth Scientific and Industrial Research
 Organization; 1993.
 Australian journal of agricultural research v. 44 (1): p.
 23-32; 1993. Includes references.
 
 Language:  English
 
 Descriptors: New South Wales; Hordeum vulgare; Cultivars; Crop
 damage; Herbicide resistance; Phytotoxicity; Chlorsulfuron;
 Rain; Temperature
 
 
 186                                   NAL Call. No.: 442.8 Z8
 Inheritance of bipyridyl herbicide resistance in Arctotheca
 calendula and Hordeum leporinum.
 Purba, E.; Preston, C.; Powles, S.B.
 Berlin, W. Ger. : Springer International; 1993 Dec.
 Theoretical and applied genetics v. 87 (5): p. 598-602; 1993
 Dec.  Includes references.
 
 Language:  English
 
 Descriptors: Arctotheca calendula; Hordeum murinum subsp.
 leporinum; Inheritance; Herbicide resistance; Paraquat;
 Diquat; Segregation; Biotypes; Genes; Dominance; Herbicide
 resistant weeds
 
 Abstract:  The mode of inheritance of resistance to bipyridyl
 herbicides in bipyridyl-resistant biotypes of Arctotheca
 calendula and of Hordeum leporinum was investigated. F1 plants
 from reciprocal crosses between diquat-resistant and -
 susceptible plants of A. calendula showed an intermediate
 response to diquat application that was nuclearly inherited.
 Treatment of F2 plants with 100 g ai ha-1 of diquat or 800 g
 ai ha-1 of paraquat killed all homozygous-susceptible plants,
 caused severe injury to heterozygous plants but only slight or
 no injury to homozygous-resistant plants. Back crosses of F1
 to susceptible plants exhibited intermediate and susceptible
 phenotypes. The observed segregation ratios in F2 and test-
 cross populations fitted predicted segregation ratios, 1:2:1
 (R:I:S) and 1:1 (I:S) respectively, showing that bipyridyl
 resistance is conferred by a single incompletely-dominant
 gene. Biotypes of paraquat-resistant and -susceptible H.
 leporinum were crossed reciprocally. F1 plants from reciprocal
 crosses showed an intermediate response to paraquat
 application. The F2 progeny showed segregation ratios that
 fitted the predicted segregation ratio of 1:2:1 (R:I:S) for
 inheritance of resistance being governed by a single
 partially-dominant gene.
 
 
 187                                   NAL Call. No.: 470 C16C
 Inheritance of two mutations conferring glyphosate tolerance
 in the fern Ceratopteris richardii.
 Chun, P.T.; Hickok, L.G.
 Ottawa, Ont. : National Research Council of Canada; 1992 May.
 Canadian journal of botany; Journal canadien de botanique v.
 70 (5): p. 1097-1099; 1992 May.  Includes references.
 
 Language:  English
 
 Descriptors: Ceratopteris; Genotypes; Herbicide resistance;
 Inheritance; Mutations; Glyphosate
 
 
 188                                  NAL Call. No.: SB951.P47
 Inhibition of acetolactate synthase in susceptible and
 resistant biotypes of Stellaria media.
 Devine, M.D.; Marles, M.A.S.; Hall, L.M.
 Essex : Elsevier Applied Science Publishers; 1991.
 Pesticide science v. 31 (3): p. 273-280; 1991.  Includes
 references.
 
 Language:  English
 
 Descriptors: Alberta; Stellaria media; Lyases; Biotypes; Cross
 resistance; Enzyme inhibitors; Herbicide resistance;
 Susceptibility; Chlorsulfuron; Sulfonylurea herbicides; Weed
 control
 
 Abstract:  Acetolactate synthase (ALS) from one susceptible
 and two chlorsulfuron-resistant biotypes of Stellaria media
 (L.) Vill. was assayed in the presence of eight known ALS
 inhibitors. As expected, ALS from the chlorsulfuron-resistant
 biotypes (R1 and R2) showed reduced sensitivity to
 chlorsulfuron and other sulfonylurea herbicides. The patterns
 of cross-resistance varied, however, indicating that the
 alteration in ALS that confers chlorsulfuron resistance does
 not confer the same level of resistance to other sulfonylurea
 herbicides. The resistant biotypes were highly cross-resistant
 to sulfometuron-methyl and DPX-A7881, but less cross-resistant
 to triasulfuron. Both R1 and R2 were highly cross-resistant to
 DTPS (N-[2,6-dichlorophenyl]-5,7-dimethyl-1,2,4-
 triazolo[1,5a]pyrimidine-2-sulfonamide), but only slightly
 cross-resistant to imazamethabenz, an imidazolinone herbicide.
 The differences in the patterns of cross-resistance observed
 presumably reflect differences in the binding affinity of the
 herbicides for the altered ALS. The data presented suggest,
 but do not confirm, that R1 and R2 contain the same ALS
 mutation.
 
 
 189                          NAL Call. No.: SB123.57.I55 1992
 Instability of herbicide resistance in transgenic suspension
 cultures and plants.
 Broer, I.; Droge, W.; Hillemann, D.; Neumann, K.; Walter, C.;
 Puhler, A. Braunschweig, Germany : Biologische Bundesanstalt
 fur Land- und Forstwirtschaft; 1992.
 Proceedings of the 2nd International Symposium on the
 Biosafety Results of Field Tests of Genetically Modified
 Plants and Microorganisms : May 11-14, 1992, Goslar, Germany :
 edited by R. Casper and J. Landsmann. p. 230-238; 1992. 
 Includes references.
 
 Language:  English
 
 Descriptors: Plants; Transgenics; Genetic engineering;
 Herbicide resistance
 
 
 190                                  NAL Call. No.: SB610.W39
 International organization for resistant pest management
 (IOPRM)-- a step toward rational resistance management
 recommendations.
 Lebaron, H.M.; Gressel, J.; Smale, B.C.; Horne, D.M.
 Champaign, Ill. : The Society; 1992 Jul.
 Weed technology : a journal of the Weed Science Society of
 America v. 6 (3): p. 765-770; 1992 Jul.  Includes references.
 
 Language:  English
 
 Descriptors: International organizations; Herbicide resistant
 weeds; Weed control; Pest management; Pest resistance
 
 
 191                                 NAL Call. No.: QH431.G452
 Interspecific hybrids between a transgenic rapeseed (Brassica
 napus) and related species: cytogenetical characterization and
 detection of the transgene.
 Kerlan, M.C.; Chevre, A.M.; Eber, F.
 Ottawa, Ontario, Canada : National Research Council Canada;
 1993 Dec. Genome / v. 36 (6): p. 1099-1106; 1993 Dec. 
 Includes references.
 
 Language:  English
 
 Descriptors: Brassica napus; Brassica oleracea; Brassica
 oleracea var. capitata; Brassica; Brassica nigra; Sinapis
 arvensis; Raphanus raphanistrum; Interspecific hybridization;
 Hybrids; Transgenic plants; Introgression; Reporter genes;
 Acyltransferases; Cytogenetics; Chromosome pairing; Meiosis;
 Glufosinate; Herbicide resistance
 
 Abstract:  In interspecific hybrids produced between a
 transgenic rapeseed, an allotetraploid species, resistant to
 herbicide, phosphinotricin, and five diploid related species.
 the risk for gene introgression in weed genomes was explored
 through cytogenetic and bar gene characterizations. Among the
 75 hybrids studied, most had the expected triploid structure,
 with the exception of B. napus--B. oleracea amphidiploid
 plants and one B. napus--S. arvensis amphidiploid plant. In
 triploid hybrid plants, the reciprocal hybrids did not exhibit
 any difference in their meiotic behavior. The comparison of
 the percentage of chromosome pairing in the hybrids with that
 of haploid rapeseed permit to conclude that allosyndesis
 between AC genomes and related species genomes took place.
 This possibility of recombination was confirmed by the
 presence of multivalent associations in all the interspecific
 hybrids. Nevertheless, in B. napus--B. adpressa hybrids a
 control of chromosome pairing seemed to exist. The possibility
 of amphidiploid plant production directly obtained in the F1
 generation increased the risk of gene dispersal. The B. napus-
 -B. oleracea amphidiploid plant presented a meiotic behavior
 more regular than that of the B. napus--S. arvensis
 amphidiploid plant. Concerning the herbicide bar gene
 characterization, the presence of the gene detected by DNA
 amplification was correlated with herbicide resistance, except
 for two plants. Different hypotheses were proposed to explain
 these results. A classification of the diploid species was
 established regarding their gene dispersal risk based on the
 rate of allosyndesis between chromosomes of AC genomes of
 rapeseed and the genomes of the related species.
 
 
 192                      NAL Call. No.: Videocassette no.1003
 Introduction to genetics and biotechnology DNA technology by
 Paul J. Bottino ; directed/recorded by Ron Young..  NAL
 genetics lecture DNA technology Bottino, P. J.
 National Agricultural Library (U.S.)
 Beltsville, Md.? : National Agricultural Library,; 1991.
 2 videocassettes (190 min.) : sd., col. ; 1/2 in. (NAL lecture
 series ; series no. 1).  VHS.  June 17, 1991.  Title on
 cassette label: NAL genetics lecture. Susan McCarthy,
 Coordinator, Plant Genome Data and Information Center.
 
 Language:  English
 
 Descriptors: Genetics; Restriction enzymes, DNA; Plant genetic
 engineering
 
 Abstract:  Discusses restriction enzymes and how they are used
 to cut DNA, restriction sites, enzyme recognition, bacterial
 plasmids, use of complementary base pairing, enzymology, and
 gel electrophoresis. Also discusses how DNA technology is use
 for plant disease, virus and herbicide resistance and for gene
 therapy.
 
 
 193                                  NAL Call. No.: SB951.P49
 Investigation of the mechanism of diclofop resistance in two
 biotypes of Avena fatua.
 Devine, M.D.; MacIsaac, S.A.; Romano, M.L.; Hall, J.C.
 Orlando, Fla. : Academic Press; 1992 Jan.
 Pesticide biochemistry and physiology v. 42 (1): p. 88-96;
 1992 Jan.  Includes references.
 
 Language:  English
 
 Descriptors: Avena fatua; Biotypes; Physiological races;
 Herbicide resistance; Diclofop; Absorption; Translocation;
 Metabolism; Metabolic detoxification; Pharmacokinetics;
 Metabolites; Phytotoxicity; Enzyme activity; Acetyl-coa
 carboxylase
 
 Abstract:  The mechanism of diclofop resistance was
 investigated in two biotypes of wild oat (Avena fatua L.) that
 show approximately 12-fold resistance to diclofop compared to
 a typical susceptible biotype. Absorption and translocation of
 14C following application of [14C]diclofop-methyl did not
 differ among the three biotypes; approximately 95% of the
 applied diclofop-methyl was absorbed into the foliage 48 hr
 after application, and most of this (> 80%) was retained in
 the treated area in all biotypes. Metabolism of diclofop-
 methyl, examined by TLC and HPLC, did not differ among the
 three biotypes. Although results of the TLC and HPLC analyses
 differed slightly, the amount of free diclofop (acid) was
 generally consistent among the three biotypes. There were no
 apparent differences in the nature of the polar metabolites
 formed in the susceptible and tolerant biotypes. Wheat, which
 is tolerant of diclofop-methyl, metabolized the herbicide
 considerably faster than the three wild oat biotypes. Acetyl-
 coenzyme A carboxylase extracted from the resistance and
 susceptible biotypes was equally sensitive to diclofop in the
 range 10(-7) to 10(-4) M, indicating that diclofop resistance
 is not due to differences at the herbicide target site.
 Further research is required to explain diclofop resistance in
 these wild oat biotypes.
 
 
 194                                    NAL Call. No.: S79 .E3
 Kenaf tolerance to various postemergence herbicides registered
 for other crops grown in the delta of Mississippi.
 Kurtz, M.E.; Weill, S.W.
 State College, Miss. : Mississippi State University,
 Agricultural and Forestry Experiment Station, 1970-; 1993 May.
 Bulletin (997): 7 p.; 1993 May.  Includes references.
 
 Language:  English
 
 Descriptors: Mississippi; Cabt; Hibiscus cannabinus; Herbicide
 resistance; Herbicides; Weed control; Phytotoxicity; Growth
 effects; Field tests
 
 
 195                                NAL Call. No.: SB610.2.B74
 Kinetics of chlorophyll fluorescence decay in triazine-
 resistant and -susceptibile weeds.
 Benyamini, Y.; Schonfeld, M.; Rubin, B.
 Surrey : BCPC Registered Office; 1991.
 Brighton Crop Protection Conference-Weeds v. 3: p. 1103-1110;
 1991.  Meeting held November 18-21, 1991, Brighton, England. 
 Includes references.
 
 Language:  English
 
 Descriptors: Weeds; Chlorophyll; Fluorescence; Herbicide
 resistance; Susceptibility; Weed biology
 
 
 196                                   NAL Call. No.: 450 P692
 Lack of cross-resistance of imazaquin-resistant Xanthium
 strumarium acetolactate synthase to flumetsulam and
 chlorimuron.
 Schmitzer, P.R.; Eilers, R.J.; Cseke, C.
 Rockville, MD : American Society of Plant Physiologists, 1926-
 ; 1993 Sep. Plant physiology v. 103 (1): p. 281-283; 1993 Sep. 
 Includes references.
 
 Language:  English
 
 Descriptors: Xanthium strumarium; Cross resistance; Herbicide
 resistant weeds; Imazaquin; Lyases; Weed control; Chlorimuron;
 Herbicides
 
 Abstract:  Acetolactate synthase (ALS) was isolated from a
 field population of cocklebur (Xanthium strumarium) that
 developed resistance to the herbicide Scepter following three
 consecutive years of application. The active ingredient of
 Scepter, imazaquin, gave an inhibitor concentration required
 to produce 50% inhibition of the enzyme activity that was more
 than 300 times greater for the resistant enzyme than for the
 wild-type cocklebur ALS. Tests with flumetsulam and
 chlorimuron show that the resistant ALS was not cross-
 resistant to these two other classes of ALS inhibitors.
 
 
 197                                     NAL Call. No.: A00109
 The latest on transgenic herbicide-tolerant crops.
 Washington, DC : National Biotechnology Policy Center of the
 National Wildlife Federation; 1991 Jun.
 The gene exchange v. 2 (2): p. 10; 1991 Jun.
 
 Language:  English
 
 Descriptors: U.S.A.; Herbicide resistance; Transgenics; Crops;
 Usda; Field tests
 
 
 198                                    NAL Call. No.: 10 J822
 The location and effects of genes modifying the response of
 wheat to the herbicide difenzoquat.
 Leckie, D.; Snape, J.W.
 Cambridge : Cambridge University Press; 1992 Feb.
 The Journal of agricultural science v. 118 (pt.1): p. 9-15;
 1992 Feb. Includes references.
 
 Language:  English
 
 Descriptors: Triticum; Polyploidy; Gene transfer; Genotypes;
 Herbicide resistance; Susceptibility; Difenzoquat
 
 
 199                                  NAL Call. No.: QK710.P55
 Magnesium deficiency enhances resistance to paraquat toxicity
 in bean leaves. Cakmak, I.; Marschner, H.
 Oxford : Blackwell Scientific Publications; 1992 Oct.
 Plant, cell and environment v. 15 (8): p. 955-960; 1992 Oct. 
 Includes references.
 
 Language:  English
 
 Descriptors: Phaseolus vulgaris; Paraquat; Phytotoxicity;
 Magnesium; Mineral deficiencies; Herbicide resistance; Leaves;
 Light intensity; Oxygen; Free radicals; Chlorophyll;
 Degradation
 
 
 200                                  NAL Call. No.: SB951.P49
 Mechanism of diclofop resistance in an Italian ryegrass
 (Lolium multiflorum Lam.) biotype.
 Gronwald, J.W.; Eberlein, C.V.; Betts, K.J.; Baerg, R.J.;
 Ehlke, N.J.; Wyse, D.L.
 Orlando, Fla. : Academic Press; 1992 Oct.
 Pesticide biochemistry and physiology v. 44 (2): p. 126-139;
 1992 Oct. Includes references.
 
 Language:  English
 
 Descriptors: Oregon; Lolium multiflorum; Biotypes; Herbicide
 resistance; Diclofop; Haloxyfop; Sethoxydim; Quizalofop;
 Cyclohexene oxime herbicides; Herbicide resistant weeds;
 Enzyme activity; Acetyl-coa carboxylase; Resistance
 mechanisms; Pharmacokinetics; Translocation; Metabolism
 
 Abstract:  The biochemical basis for diclofop resistance in an
 Italian ryegrass (Lolium multiflorum Lam.) biotype discovered
 in Oregon was examined. Herbicide rates that inhibited shoot
 growth by 50% (GR50 values) were determined for two
 aryloxyphenoxypropionic acid herbicides (diclofop, haloxyfop)
 and one cyclohexanedione herbicide (sethoxydim). As compared
 to a wild type Italian ryegrass biotype, the GR50 values for
 diclofop, haloxyfop, and sethoxydim were approximately 130-,
 22-, and 2-fold greater, respectively, for the resistant
 biotype. There were little or no differences in the retention,
 absorption, translocation, or metabolism of diclofop-methyl in
 resistant and susceptible biotypes. The susceptibility of
 acetyl-CoA carboxylase (ACCase) to inhibition by selected
 graminicide herbicides was evaluated in extracts from
 etiolated shoots of both resistant and susceptible biotypes.
 The herbicide concentrations that inhibited ACCase activity by
 50% (I50 values) for diclofop, haloxyfop, and quizalofop were
 approximately 28-, 9-, and 10-fold greater, respectively, for
 the enzyme from the resistant biotype. For the
 cyclohexanedione herbicides, sethoxydim and clethodim, the I50
 values for ACCase were similar for both biotypes. It is
 concluded that resistance to diclofop and other
 aryloxyphenoxypropionic acid herbicides in the Italian
 ryegrass biotype from Oregon is due to the presence of a
 tolerant form of ACCase. This modification confers tolerance
 to the aryloxyphenoxypropionic acids but little or no
 tolerance to the cyclohexanediones.
 
 
 201                                   NAL Call. No.: 79.8 W41
 Mechanism of inheritance of diclofop resistance in Italian
 ryegrass (Lolium multiflorum).
 Betts, K.J.; Ehlke, N.J.; Wyse, D.L.; Gronwald, J.W.; Somers,
 D.A. Champaign, Ill. : Weed Science Society of America; 1992
 Apr. Weed science v. 40 (2): p. 184-189; 1992 Apr.  Includes
 references.
 
 Language:  English
 
 Descriptors: Oregon; Lolium multiflorum; Herbicide resistance;
 Herbicide resistant weeds; Diclofop; Biotypes; Inheritance;
 Maternal effects; Phenotypes; Susceptibility; Enzyme activity;
 Acetyl-coa carboxylase
 
 Abstract:  A diclofop-methyl-resistant biotype of Italian
 ryegrass was characterized to determine the expression and
 inheritance of herbicide resistance and whether this trait was
 due to the presence of a diclofop-insensitive form of acetyl-
 coenzyme A carboxylase (ACCase). At the whole plant level, the
 resistant biotype was > 93-fold more resistant to diclofop-
 methyl than the susceptible biotype. Crosses of diclofop-
 resistant and -susceptible plants were performed to produce F1
 plants. No maternal effects were evident in responses of
 reciprocal F1 plants to diclofop. GR50 diclofop rates
 determined for resistant, F1, and susceptible plants were 15,
 6.3, and 0.16 kg ha-1, respectively. F2 populations treated
 with a 7.5 kg ha-1 rate of diclofop exhibited three injury
 response phenotypes 3 wk after treatment: a susceptible (S)
 phenotype which was killed, an intermediate resistance (I)
 phenotype with severe injury, and a resistant (R) phenotype
 with little or no injury. Testcross progeny exhibited only I
 and S phenotypes. Observed segregation of phenotypes in F2 and
 testcross populations conformed to segregation ratios
 predicted for a trait with inheritance controlled by a single
 partially dominant nuclear gene. ACCase activity determined in
 crude cell-free extracts of resistant, F1, and susceptible
 biotypes exhibited I50 values of 50, 20, and 0.7 micromolar
 diclofop, respectively. A positive relationship between the
 injury response phenotype and site of action (ACCase) response
 to diclofop was evident in both F1 and F2 populations. In
 extracts from R, I, and S phenotype F2 plants, 20 micromolar
 diclofop acid inhibited ACCase-mediated incorporation of 14C
 by 27.1, 45.1, and 78.9%, respectively. The ACCase data are
 consistent with the hypothesis that diclofop resistance in
 Italian ryegrass is conferred by a diclofop-insensitive form
 of ACCase.
 
 
 202                                  NAL Call. No.: 450 J8224
 Mechanism of isoxaben tolerance in Agrostis palustris var.
 Penncross. Heim, D.R.; Bjelk, L.A.; James, J.; Schneegurt,
 M.A.; Larrinua, I.M. Oxford : Oxford University Press; 1993
 Jul.
 Journal of experimental botany v. 264 (44): p. 1185-1189; 1993
 Jul.  Includes references.
 
 Language:  English
 
 Descriptors: Agrostis stolonifera var. palustris; Arabidopsis
 thaliana; Isoxaben; Herbicide resistance; Cellulose;
 Carbohydrate metabolism; Uptake; Binding site; Interactions;
 Metabolism; Cell wall components
 
 Abstract:  Previous work has demonstrated that isoxaben
 tolerant mutants of Arabidopsis thaliana var. Columbia are
 most likely altered at the site of isoxaben binding. The
 salient question becomes whether or not species selectivity to
 this herbicide might also be a result of differential target
 site binding. Grasses are generally more tolerant to isoxaben
 than dicots. In this communication we show that Agrostis
 palustris var. Penncross, a grass, is 83-fold more tolerant in
 a soil incorporation test and 170-fold more tolerant to
 inhibition of glucose incorporation into cellulose than is
 Arabidopsis, a dicot. Cell wall fractionation of Agrostis
 shows a specific effect on cellulose biosynthesis. At most, 5-
 fold of the 170-fold tolerance exhibited by Agrostis in terms
 of cellulose biosynthesis can be attributed to decreased
 isoxaben uptake under the test conditions. Furthermore,
 Agrostis is unable to metabolize isoxaben to any significant
 degree. Therefore, we suggest that the major portion of the
 tolerance in Agrostis might be due to differences in isoxaben
 binding.
 
 
 203                                    NAL Call. No.: QK1.A57
 Mechanisms and agronomic aspects of herbicide resistance.
 Holt, J.S.; Powles, S.B.; Holtum, J.A.M.
 Palo Alto, Calif. : Annual Reviews, Inc; 1993.
 Annual review of plant physiology and plant molecular biology
 v. 44: p. 203-209; 1993.  Literature review.  Includes
 references.
 
 Language:  English
 
 Descriptors: Crops; Herbicide resistance; Herbicide resistant
 weeds; Reviews; Plant physiology
 
 
 204                                   NAL Call. No.: SB249.N6
 Mechanisms for resistance of weeds to herbicides.
 Duke, S.O.
 Memphis, Tenn. : National Cotton Council of America, 1991-;
 1993. Proceedings / v. 3: p. 1509-1511; 1993.  Meeting held
 January 10-14, 1993, New Orleans, Louisiana.  Includes
 references.
 
 Language:  English
 
 Descriptors: Weeds; Herbicide resistance
 
 
 205                                   NAL Call. No.: 79.9 W52
 Mechanisms of resistance to acetolactate
 synthase/acetohydroxyacid synthase inhibitors.
 Shaner, D.L.
 Reno, Nev. : The Society; 1991.
 Proceedings - Western Society of Weed Science v. 44: p.
 122-125; 1991. Meeting held March 12-14, 1991, Seattle
 Washington.  Includes references.
 
 Language:  English
 
 Descriptors: Herbicide resistance; Herbicides; Mode of action;
 Enzyme inhibitors; Ligases; Resistance mechanisms
 
 
 206                            NAL Call. No.: SB957.R474 1991
 Mechanisms of resistance to herbicides.
 Dodge, A.D.
 London : Published for SCI by Elsevier Applied Science; 1991.
 Resistance '91, Achievement and Developments in Combating
 Pesticide Resistance / edited by Ian Denholm, Alan L.
 Devonshire, and Derek W. Hollomon. p. 203-217; 1991. 
 Proceedings of the SCI Symposium "Resistance '91: Achievements
 and Developments in Combating Pesticide Resistance," 15-17
 July 1991, Rothamsted Experimental Station, Harpenden, UK. 
 Includes references.
 
 Language:  English
 
 Descriptors: Weed control; Herbicide resistance; Metabolism
 
 
 207                                   NAL Call. No.: 450 P692
 Membrane response to diclofop acid is pH dependent and is
 regulated by the protonated form of the herbicide in roots of
 pea and resistant and susceptible rigid ryegrass.
 DiTomaso, J.M.
 Rockville, MD : American Society of Plant Physiologists, 1926-
 ; 1993 Aug. Plant physiology v. 102 (4): p. 1331-1336; 1993
 Aug.  Includes references.
 
 Language:  English
 
 Descriptors: Pisum sativum; Lolium rigidum; Diclofop; Organic
 acids; Herbicidal properties; Ph; Electrophysiology; Plasma
 membranes; Membrane potential; Roots; Cell walls; Herbicide
 resistance; Biotypes
 
 Abstract:  Electrophysiological studies in roots of pea (Pisum
 sativum L.) and rigid ryegrass (Lolium rigidum Gaud.)
 seedlings were conducted to elucidate the mechanism involved
 in the membrane response to the herbicide diclofop. In pea, a
 dicotyledonous plant insensitive to diclofop, membrane
 depolarization at varying pH values and herbicide
 concentrations increased at higher concentrations of the
 protonated form of diclofop acid (pKa 3.57). In unbuffered
 nutrient solution (pH 5.7), diclofop acid (50 micromolars)
 depolarized the membrane potential (Em) in roots of both
 resistant and susceptible biotypes of rigid ryegrass, whereas
 recovery of Em occurred only in the resistant biotype
 following removal of the herbicide. This differential response
 was correlated with an increase (450%) in the rate of
 acidification of the external solution by the susceptible
 biotype, and the Em differences between biotypes were
 eliminated in solutions buffered at pH 5.0 or 6.0. In
 addition, p-chloromercuribenzene-sulfonic acid did not prevent
 the depolarization of Em by 50 micromolars diclofop acid. It
 is concluded that the differential membrane response to
 diclofop acid in herbicide-resistant and -susceptible biotypes
 of rigid ryegrass is due to pH differences at the cell
 wall/plasmalemma interface. Although the membrane response is
 probably not involved in the primary inhibitory effect of
 diclofop on plant growth, it could reduce the concentration of
 the permeant protonated form of the herbicide and possibly
 could contribute to increased tolerance to diclofop and other
 weak acid herbicides.
 
 
 208                                   NAL Call. No.: 500 N813
 Metabolism of metribuzin in somaclonal variants of tomato.
 Breiland, K.; Davis, D.G.; Swanson, H.R.; Frear, D.S.; Secor,
 G. Grand Forks, N.D. : The Academy; 1991 Apr.
 Proceedings of the North Dakota Academy of Science v. 45: p.
 36; 1991 Apr. Paper presented at the 83rd Annual Meeting,
 April 25-26, 1991, Minot, North Dakota.  Includes references.
 
 Language:  English
 
 Descriptors: Lycopersicon esculentum; Somaclonal variation;
 Cultivars; Herbicide resistance; Metribuzin
 
 
 209                                  NAL Call. No.: 381 J8223
 Metabolism of sulfometuron-methyl in wheat and its possible
 role in wheat intolerance.
 Anderson, J.J.; Swain, R.S.
 Washington, D.C. : American Chemical Society; 1992 Nov.
 Journal of agricultural and food chemistry v. 40 (11): p.
 2279-2283; 1992 Nov.  Includes references.
 
 Language:  English
 
 Descriptors: Triticum aestivum; Sulfonylurea herbicides;
 Metabolism; Metabolic detoxification; Herbicide resistance
 
 Abstract:  [phenyl-(U)-(14)C]Sulfometuron-methyl was
 metabolized in excised wheat (sensitive to sulfometuron-
 methyl) to [(14)C]methyl 2-[[[[(4-(hydroxymethyl)-6-
 methylpyrimindin-2-yl)amino]
 carbonyl]amino]sulfonyl]benzoate (HM-SM) and its carbohydrate
 conjugate. This metabolic pathway is consistent with
 sulfometuron-methyl metabolism in tolerant species such as
 Bermuda grass. Sulfometuron-methyl was metabolized at a slower
 rate than metsulfuron-methyl in wheat. When plantswere exposed
 to [(14)C]methyl 4-hydroxy-2-[[[[(4-methoxy-6-methyl-1,3,5-
 triazin-2-yl)ami no]carbonyl]amino] sulfonyl]benzoate (HP-MM)
 and [(14)C]HM-SM the primary hydroxylated wheat metabolites of
 metsulfuron-methyl and sulfometuron-methyl, respectively), the
 rate of glucose conjugation of HP-MM was much faster than the
 rate of glucose conjugation of HM-SM. Along with their parent
 compounds, both HM-SM and HP-MM are potent inhibitors of wild
 mustard acetolactate synthase. These results indicate that
 wheat intolerance to sulfometuron-methyl but tolerance to the
 structurally closely related (metsulfuron-methyl) reflects not
 only a reduced ability to hydroxylate the parent molecule but
 also a reduced ability to conjugate the primary toxic
 metabolite to a nontoxic moiety.
 
 
 210                                  NAL Call. No.: QK710.P55
 Mode of action of paraquat in leaves of paraquat-resistant
 Conyza canadensis (L.) Cronq.
 Lehoczki, E.; Laskay, G.; Gaal, I.; Szigeti, Z.
 Oxford : Blackwell Scientific Publications; 1992 Jun.
 Plant, cell and environment v. 15 (5): p. 531-539; 1992 Jun. 
 Includes references.
 
 Language:  English
 
 Descriptors: Conyza canadensis; Paraquat; Herbicidal
 properties; Herbicide resistance; Herbicide resistant weeds;
 Biotypes; Phytotoxicity; Photosynthesis; Chlorophyll;
 Fluorescence; Ethanol production; Oxygen; Gas production;
 Light; Leaves; Light intensity
 
 
 211                            NAL Call. No.: SB957.R474 1991
 Modelling herbicide resistance--a study of ecological fitness.
 Mortimer, A.M.; Ulf-Hansen, P.F.; Putwain, P.D.
 London : Published for SCI by Elsevier Applied Science; 1991.
 Resistance '91, Achievement and Developments in Combating
 Pesticide Resistance / edited by Ian Denholm, Alan L.
 Devonshire, and Derek W. Hollomon. p. 148-164; 1991. 
 Proceedings of the SCI Symposium "Resistance '91: Achievements
 and Developments in Combating Pesticide Resistance," 15-17
 July 1991, Rothamsted Experimental Station, Harpenden, UK. 
 Includes references.
 
 Language:  English
 
 Descriptors: Alopecurus myosuroides; Herbicide resistance
 
 
 212                                    NAL Call. No.: 472 N42
 Modified wheat paves the way to bumper harvest.
 Coghlan, A.
 London, Eng. : New Science Publications; 1992 Jul27.
 New scientist v. 134 (1827): p. 19; 1992 Jul27.
 
 Language:  English
 
 Descriptors: Florida; Triticum aestivum; Genetic engineering;
 Herbicide resistance
 
 
 213                   NAL Call. No.: LU378.76 L930d 1991 sath
 The molecular basis of imidazolinone herbicide resistance in
 arabidopsis thalian var. columbia.
 Sathasivan, Kanagasabapathi,
 1991; 1991.
 x, 67 leaves : ill. ; 29 cm.  Vita.  Abstract.  Includes
 bibliographical references (leaves 60-62).
 
 Language:  English
 
 Descriptors: Plants, Effect of herbicides on; Herbicides;
 Imidazoline
 
 
 214                                   NAL Call. No.: 450 P692
 Molecular basis of imidazolinone herbicide resistance in
 Arabidopsis thaliana var Columbia.
 Sathasivan, K.; Haughn, G.W.; Murai, N.
 Rockville, Md. : American Society of Plant Physiologists; 1991
 Nov. Plant physiology v. 97 (3): p. 1044-1050; 1991 Nov. 
 Includes references.
 
 Language:  English
 
 Descriptors: Arabidopsis thaliana; Imidazolinone herbicides;
 Herbicide resistance; Plant breeding; Genetic transformation;
 Gene transfer; Mutants; Genetic variation
 
 Abstract:  Acetolactate synthase (ALS), the first enzyme in
 the biosynthetic pathway of leucine, isoleucine, and valine,
 is inhibited by imidazolinone herbicides. To understand the
 molecular basis of imidazolinone resistance, we isolated the
 ALS gene from an imazapyr-resistant mutant GH90 of Arabidopsis
 thaliana. DNA sequence analysis of the mutant ALS gene
 demonstrated a single-point mutation from G to A at nucleotide
 1958 of the ALS-coding sequence. This would result in Ser to
 Asn substitution at residue 653 near the carboxyl terminal of
 the matured ALS. The mutant ALS gene was introduced into
 tobacco using Agrobacterium-mediated transformation.
 Imidazolinone-resistant growth of transformed calli and leaves
 of transgenic plants was 100-fold greater than that of
 nontransformed control plants. The relative levels of
 imidazolinone-resistant ALS activity correlated with the
 amount of herbicide-resistant growth in the leaves of
 transgenic plants. Southern hybridization analysis confirmed
 the existence of transferred ALS gene in the transformant
 showing high imazapyr resistance. The results demonstrate that
 the mutant ALS gene confers resistance to imidazolinone
 herbicides. This is the first report, to our knowledge, of the
 molecular basis of imidazolinone resistance in plants.
 
 
 215                                  NAL Call. No.: QK710.P62
 The molecular basis of resistance to the herbicide
 norflurazon. Chamovitz, D.; Pecker, I.; Hirschberg, J.
 Dordrecht : Kluwer Academic Publishers; 1991 Jun.
 Plant molecular biology : an international journal on
 fundamental research and genetic engineering v. 16 (6): p.
 967-974; 1991 Jun.  Includes references.
 
 Language:  English
 
 Descriptors: Synechococcus; Genes; Cloning; Nucleotide
 sequences; Enzymes; Norflurazon; Herbicide resistance; Amino
 acid sequences; Models; Plants; Restriction mapping; Mutations
 
 Abstract:  We have cloned and sequenced a gene, pds, from the
 cyanobacterium Synechococcus PCC7942 that is responsible for
 resistance to the bleaching herbicide norflurazon. A point
 mutation in that gene, leading to an amino acid substitution
 from valine to glycine in its polypeptide product, was found
 to confer this resistance. Previous studies with herbicide-
 resistant mutants have indicated that this gene encodes
 phytoene desaturase (PDS), a key enzyme in the biosynthesis of
 carotenoids. A short amino acid sequence that is homologous to
 conserved motifs in the binding sites for NAD(H) and NADP(H)
 was identified in PDS, suggesting the involvement of these
 dinucleotides as cofactors in phytoene desaturation.
 
 
 216                                  NAL Call. No.: SB610.W39
 Monitoring the occurrence of sulfonylurea-resistant prickly
 lettuce (Lactuca serriola).
 Alcocer-Ruthling, M.; Thill, D.C.; Mallory-Smith, C.
 Champaign, Ill. : The Society; 1992 Apr.
 Weed technology : a journal of the Weed Science Society of
 America v. 6 (2): p. 437-440; 1992 Apr.  Includes references.
 
 Language:  English
 
 Descriptors: Idaho; Lactuca serriola; Herbicide resistant
 weeds; Sulfonylurea herbicides; Herbicide resistance;
 Metsulfuron; Sulfometuron; Surveys; Biotypes; Population
 dynamics
 
 
 217                                  NAL Call. No.: 64.8 C883
 Monogenic dominant sulfonylurea resistance in sugarbeet from
 somatic cell selection.
 Saunders, J.W.; Acquaah, G.; Renner, K.A.; Doley, W.P.
 Madison, Wis. : Crop Science Society of America; 1992 Nov.
 Crop science v. 32 (6): p. 1357-1360; 1992 Nov.  Includes
 references.
 
 Language:  English
 
 Descriptors: Beta vulgaris; Herbicide resistance;
 Chlorsulfuron; Inheritance; Cell culture; Culture media;
 Somatic mutations; Dominance; Genes; Somaclonal variation
 
 Abstract:  Injury to sugarbeet, Beta vulgaris L., from
 sulfonylurea herbicide residues from preceding cropping years
 has kindled interest in developing resistant cultivars. This
 study was conducted to obtain chlorsulfuron (2-chloro-N-[[(4-
 methoxy-6-methyl-1,3,5-triazin-2-yl)amino]carbonyl]
 benzenesulfonamide) resistance from cell cultures and to
 determine its inheritance and magnitude. Utilizing annual
 diploid sugarbeet clone REL-1, dispersed suspension cultures
 were initiated from callus induced on leaf disks cultured on a
 modified Murashige and Skoog (MS) agar medium + 1.0 mg L-1 N6-
 benzyladenine (BA) and placed in the liquid form of the same
 medium. Unmutagenized cell clusters were plated on solid
 medium containing 2.8 micromolar chlorsulfuron in MS + 1.0 mg
 L-1 BA. A single colony arose, from which shoots were
 regenerated. Shoots were resistant to 28 nM chlorsulfuron, a
 concentration that killed similar shoots of REL-1. Resistance
 (designated Sur) was inherited as a monogenic dominant. In
 vitro shoot resistance to chlorsulfuron was 300 to 1000-fold
 greater than in REL-1. Resistance was also expressed in leaf
 disk expansion in vitro with MS + 1.0 mg L-1 BA.
 
 
 218                                  NAL Call. No.: 442.8 Z34
 Multiple resistance to sulfonylureas and imidazolinones
 conferred by an acetohydroxyacid synthase gene with separate
 mutations for selective resistance.
 Hattori, J.; Rutledge, R.; Labbe, H.; Brown, D.; Sunohara, G.;
 Miki, B. Berlin, W. Ger. : Springer International; 1992 Mar.
 M G G : Molecular and general genetics v. 232 (2): p. 167-173;
 1992 Mar. Includes references.
 
 Language:  English
 
 Descriptors: Arabidopsis thaliana; Nicotiana tabacum; Genetic
 transformation; Transgenics; Genes; Oxo-acid-lyases; Alleles;
 Mutants; Herbicide resistance; Chlorsulfuron; Imidazolinone
 herbicides; Nucleotide sequences; Enzyme activity; Amino acid
 sequences; Induced mutations
 
 Abstract:  The acetohydroxyacid synthase (AHAS) gene from the
 Arabidopsis thaliana mutant line GH90 carrying the
 imidazolinone resistance allele imr1 was cloned. Expression of
 the AHAS gene under the control of the CaMV 35S promoter in
 transgenic tobacco resulted in selective imidazolinone
 resistance, confirming that the single base-pair change found
 near the 3' end of the coding region of this gene is
 responsible for imidazolinone resistance. A chimeric AHAS gene
 containing both the imr1 mutation and the csr1 mutation,
 responsible for selective resistance to sulfonylurea
 herbicides, was constructed. It conferred on transgenic
 tobacco plants resistance to both sulfonylurea and
 imidazolinone herbicides. The data illustrate that a multiple-
 resistance phenotype can be achieved in an AHAS gene through
 combinations of separate mutations, each of which individually
 confers resistance to only one class of herbicides.
 
 
 219                                    NAL Call. No.: Q11.J68
 Mutant weeds of Iowa. V. S-triazine resistant Setaria faberi
 Herrm. Thornhill, R.; Dekker, J.
 Cedar Falls, Iowa : The Academy; 1993 Mar.
 The Journal of the Iowa Academy of Science : JIAS v. 100 (1):
 p. 13-14; 1993 Mar.  Includes references.
 
 Language:  English
 
 Descriptors: Iowa; Setaria faberi; Herbicide resistant weeds;
 Mutants; Triazine herbicides
 
 
 220                                   NAL Call. No.: QH301.J6
 A mutation in the alpha 1-tubulin gene of Chlamydomonas
 reinhardtii confers resistance to anti-microtubule herbicides.
 James, S.W.; Silflow, C.D.; Stroom, P.; Lefebvre, P.A.
 Cambridge : The Company of Biologists Limited; 1993 Sep.
 Journal of cell science v. 106 (pt.1): p. 209-218; 1993 Sep. 
 Includes references.
 
 Language:  English
 
 Descriptors: Chlamydomonas reinhardtii; Induced mutations;
 Tubulin; Structural genes; Alleles; Gene mapping; Linkage
 groups; Herbicide resistance; Amiprofos-methyl; Oryzalin;
 Microtubules; Semidominance; Segregation; Nucleotide sequences
 
 
 221                                   NAL Call. No.: 442.8 Z8
 Mutations in corn (Zea mays L.) conferring resistance to
 imidazolinone herbicides.
 Newhouse, K.; Singh, B.; Shaner, D.; Stidham, M.
 Berlin, W. Ger. : Springer International; 1991.
 Theoretical and applied genetics v. 83 (1): p. 65-70; 1991. 
 Includes references.
 
 Language:  English
 
 Descriptors: Zea mays; Induced mutations; Oxo-acid-lyases;
 Alleles; Semidominant genes; Enzyme activity; Herbicide
 resistance; Imazethapyr; Imazaquin; Sulfometuron; Inheritance;
 Crossing; Inbred lines
 
 Abstract:  Three corn (Zea mays L.) lines resistant to
 imidazolinone herbicides were developed by in vitro selection
 and plant regeneration. For all three lines, resistance is
 inherited as a single semidominant allele. The resistance
 alleles from resistant lines XA17, XI12, and QJ22 have been
 crossed into the inbred line B73, and in each case homozygotes
 are tolerant of commercial use rates of imidazolinone
 herbicides. All resistant selections have herbicide-resistant
 forms of acetohydroxyacid synthase (AHAS), the known site of
 action of imidazolinone herbicides. The herbicide-resistant
 phenotypes displayed at the whole plant level correlate
 directly with herbicide insensitivity of the AHAS activities
 of the selections. The AHAS activities from all three
 selections have normal feedback regulation by valine and
 leucine, and plants containing the mutations display a normal
 phenotype.
 
 
 222                                    NAL Call. No.: 450 N42
 Natural tolerance of cyanobacteria to the herbicide
 glyphosate. Powell, H.A.; Kerby, N.W.; Rowell, P.
 Cambridge : Cambridge University Press; 1991 Nov.
 The New phytologist v. 119 (3): p. 421-426; 1991 Nov. 
 Includes references.
 
 Language:  English
 
 Descriptors: Anabaena variabilis; Glyphosate; Phytotoxicity;
 Herbicide resistance
 
 
 223                            NAL Call. No.: SB957.R474 1991
 The needs for new herbicide-resistant crops.
 Gressel, J.
 London : Published for SCI by Elsevier Applied Science; 1991.
 Resistance '91, Achievement and Developments in Combating
 Pesticide Resistance / edited by Ian Denholm, Alan L.
 Devonshire, and Derek W. Hollomon. p. 283-294; 1991. 
 Proceedings of the SCI Symposium "Resistance '91: Achievements
 and Developments in Combating Pesticide Resistance," 15-17
 July 1991, Rothamsted Experimental Station, Harpenden, UK. 
 Includes references.
 
 Language:  English
 
 Descriptors: Plant breeding; Genetic resistance; Herbicide
 resistance
 
 
 224                                  NAL Call. No.: SB951.P47
 Negative cross-resistance to bentazone and pyridate in
 atrazine-resistant Amaranthus cruentus and Amaranthus hybridus
 biotypes.
 Prado, R. de; Sanchez, M.; Jorrin, J.; Dominguez, C.
 Essex : Elsevier Applied Science Publishers; 1992.
 Pesticide science v. 35 (2): p. 131-136; 1992.  Includes
 references.
 
 Language:  English
 
 Descriptors: Spain; Amaranthus cruentus; Amaranthus hybridus;
 Herbicide resistance; Cross resistance; Atrazine; Cyanazine;
 Acetochlor; Alachlor; Bentazone; Propachlor; Pyridate; Mcpa;
 Phytotoxicity; Photosynthesis; Inhibition; Chloroplasts;
 Chlorophyll
 
 Abstract:  Plants of Amaranthus cruentus and Amaranthus
 hybridus resistant to atrazine and cyanazine were found in
 maize fields in north-eastern Spain. Both resistant biotypes
 survived doses of 5 kg ha-1 of atrazine and 2-4 kg ha-1 of
 cyanazine but were controlled by lower doses of bentazone and
 pyridate than were susceptible biotypes. Such a negative
 cross-resistance was not found for chloroacetamides and MCPA.
 Chlorophyll fluorescence studies revealed that atrazine,
 bentazone, cyanazine and pyridate (10 mg litre-1) caused
 inhibition of photosynthetic electron transport in susceptible
 leaves, while in resistant plants, atrazine and cyanazine had
 no effect. Conversely, bentazone and pyridate inhibited
 photosynthesis to a greater extent in resistant than in
 susceptible biotypes. Isolated chloroplast membranes from
 resistant biotypes showed resistance factors of 366 and 501 to
 atrazine and 39 and 60 to cyanazine for A. hybridus and A.
 cruentus, respectively. Bentazone and pyridate were found to
 be more effective in chloroplasts of the resistant biotypes
 than those of the susceptible plants. It is suggested that
 enhanced susceptibility to bentazone and pyridate in triazine-
 resistant A. cruentus and A. hybridus biotypes may be
 associated with the alteration of the D-1 polypeptide subunit
 of photosystem II, as found in triazine-resistant plants.
 
 
 225                                NAL Call. No.: SB610.2.B74
 Nitrodiphenyl ether and phenylimide resistance of a tobacco
 biotype is due to enhanced inducibility of its antioxidant
 systems.
 Gullner, G.; Kiraly, L.; Komives, T.
 Surrey : BCPC Registered Office; 1991.
 Brighton Crop Protection Conference-Weeds v. 3: p. 1111-1118;
 1991.  Meeting held November 18-21, 1991, Brighton, England. 
 Includes references.
 
 Language:  English
 
 Descriptors: Nicotiana; Antioxidants; Biotypes; Herbicide
 resistance
 
 
 226                                  NAL Call. No.: SB951.P49
 A novel pattern of herbicide cross-resistance in a
 trifluralin-resistant biotype of green foxtail [Setaria
 viridis (L.) Beauv.].
 Smeda, R.J.; Vaughn, K.C.; Morrison, I.N.
 Orlando, Fla. : Academic Press; 1992 Mar.
 Pesticide biochemistry and physiology v. 42 (3): p. 227-241;
 1992 Mar. Includes references.
 
 Language:  English
 
 Descriptors: Manitoba; Setaria viridis; Biotypes; Herbicide
 resistance; Herbicide resistant weeds; Cross resistance;
 Trifluralin; Herbicides; Dinitroaniline herbicides; Resistance
 mechanisms; Propyzamide; Terbucarb; Amiprofos-methyl; Propham;
 Chlorthal-dimethyl; Barban; Chlorpropham
 
 Abstract:  A trifluralin-resistant (R) biotype of Setaria
 viridis is found in areas of Manitoba, Canada where
 trifluralin is utilized its the principal or sole herbicide.
 In this study, we examine the cross-resistance pattern of this
 biotype to other mitotic disrupter herbicides utilizing growth
 measurements and electron microscopy to monitor the
 resistance. Compared to a trifluralin-susceptible (S) biotype,
 the R biotype is cross-resistant to all dinitroaniline
 herbicides tested, with I50 R/S ratios [the concentration of
 herbicide required to inhibit root growth of the R biotype by
 50% divided by the concentration which induces the same effect
 for the S biotype] ranging from 1.6 to 14.8. This R biotype is
 also cross-resistant at about the same level to
 amiprophosmethyl and dithiopyr, but exhibits no resistance to
 pronamide, sindone B, barban, or the microtubule stabilizer
 taxol. The highest level of resistance is to the structurally
 unrelated herbicides DCPA (I50, R/S > 50) and terbutol (I50
 R/S = 13.4). This is the first reported incidence of
 resistance to these two herbicides. Ultrastructural
 observations show herbicide-induced abnormalities are either
 reduced or absent in the R biotype. The S biotype is actually
 less susceptible to chlorpropham and propham (R/S I50) = 0.7)
 than the R biotype. The high level of resistance to the
 phragmoplast-disrupting microtubule herbicide DCPA, as well as
 terbutol, and a lower level of resistance to a number of other
 tubulin-interacting microtubule disrupters, indicate that the
 R biotype may contain an alteration in a cytoskeletal protein
 that stabilizes phragmoplast microtubule arrays.
 
 
 227                                  NAL Call. No.: QD435.D57
 Nucleotide sequence of a 2kb plasmid from Pseudomonas cepacia
 implicated in the degradation of phenylcarbamate herbicides.
 Gaubier, P.; Vega, D.; Cooke, R.
 Chur ; New York : Harwood Academic Publishers, 1990-; 1992.
 DNA sequence : the journal of DNA sequencing and mapping v. 2
 (4): p. 269-271; 1992.  Includes references.
 
 Language:  English
 
 Descriptors: Pseudomonas cepacia; Plasmids; Nucleotide
 sequences; Herbicide resistance; Carbamate herbicides;
 Microbial degradation; Amino acid sequences
 
 Abstract:  The complete nucleotide sequence of a very small
 plasmid whose presence and level in Pseudomonas cepacia have
 been linked to herbicide resistance is presented. The
 structural features of the plasmid are discussed.
 
 
 228                                  NAL Call. No.: QK710.P62
 Nucleotide sequence of the phytoene desaturase gene from
 Synechocystis sp. PCC 6803 and characterization of a new
 mutation which confers resistance to the herbicide
 norflurazon.
 Martinez-Ferez, I.M.; Vioque, A.
 Dordrecht : Kluwer Academic Publishers; 1992 Mar.
 Plant molecular biology : an international journal on
 molecular biology, biochemistry and genetic engineering v. 18
 (5): p. 981-983; 1992 Mar. Includes references.
 
 Language:  English
 
 Descriptors: Cyanobacteria; Genes; Enzymes; Nucleotide
 sequences; Mutations; Herbicide resistance; Norflurazon; Amino
 acid sequences
 
 
 229                                   NAL Call. No.: 450 P692
 On the mechanism of resistance to paraquat in Hordeum glaucum
 and H. leporinum: Delayed inhibition of photosynthetic O2
 evolution after paraquat application.
 Preston, C.; Holtum, J.A.M.; Powles, S.B.
 Rockville, MD : American Society of Plant Physiologists, 1926-
 ; 1992 Oct. Plant physiology v. 100 (2): p. 630-636; 1992 Oct. 
 Includes references.
 
 Language:  English
 
 Descriptors: Hordeum glaucum; Hordeum murinum subsp.
 leporinum; Paraquat; Herbicide resistance; Herbicide resistant
 weeds; Photosynthesis; Oxygen; Gas production; Biotypes;
 Translocation; Leaves; Diquat
 
 Abstract:  The mechanism of resistance to paraquat was
 investigated in biotypes of Hordeum glaucum Steud. and H.
 leporinum Link. with high levels of resistance. Inhibition of
 photosynthetic O2 evolution after herbicide application was
 used to monitor the presence of paraquat at the active site.
 Inhibition of photosynthetic O2 evolution after paraquat
 application was delayed in both resistant biotypes compared
 with the susceptible biotypes; however, this differential was
 more pronounced in the case of H. glaucum than in H.
 leporinum. Similar results could be obtained with the related
 herbicide diquat. Examination of the concentration dependence
 of paraquat-induced inhibition of evolution showed that the
 resistant H. glaucum biotype was less affected by herbicide
 compared with the susceptible biotype 3 h after treatment at
 most rates. The resistant H. leporinum biotype, in contrast,
 was as inhibited as the susceptible biotype except at the
 higher rates. In all cases photosynthetic evolution was
 dramatically inhibited 24 h after treatment. Measurement of
 the amount of paraquat transported to the young tissue of
 these plants 24 h after treatment showed 57% and 53%
 reductions in the amount of herbicide transported in the case
 of the resistant H. glaucum and H. leporinum biotypes,
 respectively, compared with the susceptible biotypes. This was
 associated with 62% and 66% decreases in photosynthetic
 evolution of young leaves in the susceptible H. glaucum and H.
 leporinum biotypes, respectively, a 39% decrease in activity
 for the resistant H. leporinum biotype, but no change in the
 resistant H. glaucum biotype. Photosynthetic evolution of leaf
 slices from resistant H. glaucum was not as inhibited by
 paraquat compared with the susceptible biotype; however, those
 of resistant and susceptible biotypes of H. leporinum were
 equally inhibited by paraquat. Paraquat resistance in these
 two biotypes appears to be a consequence of reduced movement
 of the herbicide in the resistant plants; however, the
 mechanism involved is not the same in H. glaucum as in H.
 leporinum.
 
 
 230                                   NAL Call. No.: 442.8 Z8
 The origin and evolution of weed beets: consequences for the
 breeding and release of herbicide-resistant transgenic sugar
 beets.
 Boudry, P.; Morchen, M.; Saumitou-Laprade, P.; Vernet, P.; Van
 Dijk, H. Berlin, W. Ger. : Springer International; 1993 Dec.
 Theoretical and applied genetics v. 87 (4): p. 477-478; 1993
 Dec.  Includes references.
 
 Language:  English
 
 Descriptors: France; Cabt; Beta vulgaris; Beta vulgaris var.
 saccharifera; Weeds; Biotypes; Evolution; Mitochondrial  DNA;
 Chloroplasts; Dna; Restriction fragment length polymorphism;
 Annual habit; Alleles; Dominance; Pollination; Hybridization;
 Cultivars; Life cycle; Weed biology; Maternal effects;
 Chloroplast genetics; Genotypes; Mitochondrial genetics;
 Cytoplasmic male sterility
 
 Abstract:  Populations of weed beets have expanded into
 European sugar beet production areas since the 1970s, thereby
 forming a serious new weed problem for this crop. We sampled
 seeds in different French populations and studied
 mitochondrial DNA, chloroplast DNA and life-cycle variability.
 Given the maternal inheritance of the mitochondrial and
 chloroplastic genomes and the nuclear determinism of the
 annual habit, we were able to determine the maternal origin
 and evolution of these weed beet populations. Our study shows
 that they carry the dominant allele "B" for annual habit at
 high frequency. The main cytoplasmic DNA type found in
 northern weed beet populations is the cytoplasmic male-sterile
 type characteristic of sugar beets. We were able to determine
 that these populations arise from seeds originating from the
 accidental pollinations of cultivated beets by adventitious
 beets in the seed production area, which have been transported
 to the regions where sugar beets are cultivated. These seeds
 are supposedly the origin of the weed forms and a frequently
 disturbed cultivated environment has selected for annual habit
 and early flowering genotypes. We discuss the consequences of
 the weed beet populations for the breeding, seed production
 and release of herbicide-resistant transgenic sugar beets.
 
 
 231                                     NAL Call. No.: SB1.H6
 Ornamental grass tolerance to postemergence grass herbicides.
 Hubbard, J.; Whitwell, T.
 Alexandria, Va. : The American Society for Horticultural
 Science; 1991 Dec. HortScience : a publication of the American
 Society for Horticultural Science v. 26 (12): p. 1507-1509;
 1991 Dec.  Includes references.
 
 Language:  English
 
 Descriptors: Grasses; Ornamental herbaceous plants; Herbicide
 resistance; Calamagrostis; Cortaderia; Eragrostis; Erianthus;
 Miscanthus; Sorghastrum; Spartina; Panicum; Sethoxydim;
 Fenoxaprop; Fluazifop-p; Phytotoxicity; Application rates;
 Abiotic injuries
 
 Abstract:  Twelve ornamental grasses from the genera
 Calamagrostis, Cortaderia, Eragrostis, Erianthus, Miscanthus,
 Sorghastrum, Spartina, Panicum, and Pennisetum were evaluated
 for tolerance to the postemergence herbicides fenoxaprop-
 ethyl, fluazifop-P, and sethoxydim at 0.4 kg a.i./ha.
 Calamagrostis was uninjured by fenoxaprop-ethyl as measured by
 visual injury ratings, height, and foliage dry weight.
 Greenhouse studies evaluated the tolerance of three
 Calamagrostis cultivars to fenoxaprop-ethyl rates of 0.4 to
 3.2 kg a.i./ha with no observed visual injury from any
 treatment. However, the expansion rate of the youngest
 Calamagrostis leaf was reduced linearly with increasing
 herbicide rates each day after application. The highest rate
 (3.2 kg a.i./ha) reduced the leaf expansion rate by 1 day and
 all other rates by 3 days after treatment. Leaf expansion rate
 differed between Calamagrostis cultivars at different times
 after herbicide treatment. Dry weight of Calamagrostis
 arundinacea 'Karl Foerster' was reduced at 4 weeks after
 treatment but not at 10 weeks after treatment.
 
 
 232                                  NAL Call. No.: 442.8 Z34
 Overproduction by gene amplification of the multifunctional
 arom protein confers glyphosate tolerance to a plastid-free
 mutant of Euglena gracilis. Reinbothe, S.; Ortel, B.;
 Parthier, B.
 Berlin, W. Ger. : Springer International; 1993 Jun.
 Molecular & general genetics : MGG v. 239 (3): p. 416-424;
 1993 Jun.  Includes references.
 
 Language:  English
 
 Descriptors: Euglena gracilis; Amplification; Genes; Plant
 proteins; Glyphosate; Herbicide resistance; Enzyme activity;
 Alkyl (aryl) transferases; Alcohol oxidoreductases; Kinases;
 Messenger  RNA; Plastids; Mutants; Amino acid metabolism;
 Amino acids
 
 Abstract:  Cells of the plastid-free mutant line of Euglena
 gracilis var. bacillaris, W10BSmL, can be adapted to
 glyphosate [N-(phosphonomethyl)glycine] by gradually
 increasing the concentration of the herbicide in the culture
 medium. The molecular basis of glyphosate tolerance is the
 selective ca. ten-fold overproduction of the multifunctional
 arom protein catalyzing steps 2-6 in the pre-chorismate
 pathway. Determination of 5-enolpyru-vylshikimate-3-phosphate
 (EPSP) synthase (E.C.2.5.1.19), shikimate:NADP+ oxidoreductase
 (E.C.1.1.1.25) and shikimate kinase (E.C.2.7.1.71) activities
 after non-denaturing gel electrophoresis, in combination with
 two-dimensional separations, revealed an increase in all three
 enzyme activities associated with overproduction of a 165 kDa
 protein in cells adapted to 6 mM glyphosate. Further evidence
 for an involvement of the multifunctional arom protein in
 aromatic amino acid synthesis in the plastid-free W10BSmL
 cells was obtained by Northern hybridization with ARO1-, aroA-
 , aroL- and aroE-specific Saccharomyces cerevisiae gene probes
 encoding the entire arom protein or parts of the EPSP
 synthase, shikimate: NADP+ oxidoreductase and shikimate kinase
 domains, respectively. Overproduction in adapted relative to
 control cells of a 5.3 kb transcript that cross-hybridized
 with all of the different probes could be demonstrated. The
 elevated content of the arom transcript correlated with a
 selective amplification of two out of five genomic sequences
 that hybridized with the S. cerevisiae ARO1 gene probe in
 Southern blots. One of the amplified genomic fragments is
 assumed to encode the previously identified monofunctional 59
 kDa EPSP synthase, which is thought to be an organellar
 protein, that accumulates to a certain extent in its
 enzymatically active precursor form of 64.5 kDa in the
 plastid-free W10BSmL cells.
 
 
 233                                   NAL Call. No.: 450 P692
 Overproduction of gamma-linolenic and eicosapentaenoic acids
 by algae. Cohen, Z.; Didi, S.; Heimer, Y.M.
 Rockville, Md. : American Society of Plant Physiologists; 1992
 Feb. Plant physiology v. 98 (2): p. 569-572; 1992 Feb. 
 Includes references.
 
 Language:  English
 
 Descriptors: Spirulina; Algae; Biosynthesis; Linolenic acid;
 Eicosapentaenoic acid; Genetic regulation; Cell lines;
 Herbicide resistance; Plant breeding; Selection; High yielding
 varieties
 
 Abstract:  The pharmaceutical interest and limited
 availability of gamma-linolenic acid (GLA) and
 eicosapentaenoic acid (EPA) prompted the search for genetic
 means for increasing the production of these fatty acids from
 algal sources. Cell lines of Spirulina platensis and
 Porphyridium cruentum resistant to the growth inhibition of
 the herbicide Sandoz 9785 were selected by serial transfers of
 the culture in the presence of increasing concentrations of
 the herbicide. The resistant cell lines of S. platensis
 overproduced GLA and those of P. cruentum overproduced EPA and
 were stable for at least 50 generations in the absence of the
 inhibitor.
 
 
 234                                   NAL Call. No.: 100 L939
 Overtop applications of Buctril controls broadleaf weeds in
 transgenic cotton. Crawford, S.H.
 Baton Rouge, La. : The Station; 1993.
 Louisiana agriculture - Louisiana Agricultural Experiment
 Station v. 36 (1): p. 23; 1993.
 
 Language:  English
 
 Descriptors: Louisiana; Gossypium hirsutum; Weed control;
 Bromoxynil; Transgenics; Herbicide resistance; Field tests
 
 
 235                                 NAL Call. No.: SB950.A1P3
 Oxyflurofen tolerance and weed control in young papaya.
 Nishimoto, R.K.
 London : Taylor & Francis Ltd., 1993-; 1993 Jul.
 International journal of pest management v. 39 (3): p.
 366-369; 1993 Jul. Includes references.
 
 Language:  English
 
 Descriptors: Hawaii; Cabt; Carica papaya; Herbicide
 resistance; Age of trees; Plant height; Susceptibility;
 Chemical control; Weed control; Bidens pilosa; Oxyfluorfen;
 Phytotoxicity; Abiotic injuries
 
 
 236                                  NAL Call. No.: SB951.P49
 Paraquat resistance and its inheritance in seed germination of
 the foliar-resistant biotypes of Erigeron canadensis L. and E.
 sumatrensis Retz. Yamasue, Y.; Kamiyama, K.; Hanioka, Y.;
 Kusanagi, T.
 Orlando, Fla. : Academic Press; 1992 Sep.
 Pesticide biochemistry and physiology v. 44 (1): p. 21-27;
 1992 Sep.  Includes references.
 
 Language:  English
 
 Descriptors: Erigeron sumatrensis; Conyza canadensis;
 Biotypes; Herbicide resistant weeds; Paraquat; Herbicide
 resistance; Inheritance; Seed germination; Foliar application;
 Genes; Pharmacokinetics
 
 Abstract:  Seeds of the foliar-resistant biotypes of Erigeron
 canadensis L. and E. sumatrensis Retz. to paraquat (1,1'-
 dimethyl-4,4'-bipyridinium ion) were studied with respect to
 resistance at germination. Threshold concentrations of the
 herbicide in foliar susceptibility of seedlings were 10(-4)
 and 10(-6) M for the resistant and susceptible biotypes of E.
 canadensis, respectively. The concentrations in seed
 susceptibility at germination were 10(-5) and 10(-7) M for the
 respective biotypes. Seeds of the resistant biotype of E.
 sumatrensis showed less resistance at seed germination than
 those of E. canadensis. The resistant and susceptible biotypes
 of E. canadensis were reciprocally crossed to make a
 comparison in inheritance between the foliar resistance and
 seed resistance at germination. In the F2 generation, the
 ratios of foliar-resistant and susceptible seedlings at 10(-5)
 M fitted well to a 3:1 ratio, indicating that the resistance
 was controlled by a single nuclear gene. In seed resistance,
 three-fourths of the F2 seeds were resistant at 10(-5) M,
 suggesting that a single gene also controlled the resistance.
 These results suggested the possibility that a common
 mechanism of paraquat resistance exists between the
 photosynthetic and nonphotosynthetic organs.
 
 
 237                                  NAL Call. No.: QK725.P54
 Paraquat tolerance in a photomixotrophic culture of
 Chenopodium rubrum. Bhargava, S.
 Berlin, W. Ger. : Springer International; 1993.
 Plant cell reports v. 12 (4): p. 230-232; 1993.  Includes
 references.
 
 Language:  English
 
 Descriptors: Chenopodium rubrum; Cell cultures; Paraquat;
 Herbicide resistance; Weed biology; Growth; Chemical
 composition; Chlorophyll; Photosystem i; Enzyme activity;
 Superoxide dismutase; Peroxidase; Catalase; Lines; Genetic
 variation; Metabolic detoxification
 
 Abstract:  A paraquat tolerant line of Chenopodium rubrum has
 been compared with paraquat susceptible cultures, in terms of
 growth, chlorophyll content, photosystem I partial reactions,
 and the activities of some enzymes involved in detoxification
 of harmful oxygen radicals. Results indicate that paraquat
 tolerance is manifested through increased activity of
 superoxide dismutase, peroxidase and catalase, in the tolerant
 line, only in the presence of paraquat. The behaviour of the
 paraquat tolerant and susceptible cultures in the absence of
 paraquat is quite similar.
 
 
 238                                   NAL Call. No.: 79.8 W41
 Photoacoustic spectroscopy as a tool for monitoring herbicide
 effects on triazine-resistant and -susceptible biotypes of
 black nightshade (Solanum nigrum).
 Fuks, B.; Homble, F.; Van Eycken, F.; Figeys, H.; Lannoye,
 R.L. Champaign, Ill. : Weed Science Society of America; 1992
 Jul. Weed science v. 40 (3): p. 371-377; 1992 Jul.  Includes
 references.
 
 Language:  English
 
 Descriptors: Solanum nigrum; Biotypes; Herbicide resistant
 weeds; Atrazine; Diuron; Herbicide resistance; Detection;
 Monitoring; Spectroscopy; Photosynthesis
 
 Abstract:  Photoacoustic spectroscopy was used to study
 effects of atrazine and diuron on excised leaves of triazine-
 susceptible (S) and -resistant (R) biotypes of black
 nightshade. Changes of oxygen and photothermal components were
 compared to photochemical fluorescence quenching obtained by
 fluorimetry. After 1 h incubation in an aqueous solution of
 atrazine (0 to 200 micromole), oxygen component of the
 photoacoustic signal was strongly decreased in the S biotype
 while the R biotype was not affected. Also, reoxidation of the
 primary quinone acceptor (QA(-1)) of photosystem (PS) II of
 the S biotype was lower than that of the R biotype. With
 diuron treatments, changes in the characteristics of these
 biophysical signals were the same in both R and S biotypes.
 Both oxygen component and photochemical fluorescence quenching
 were decreased in treated leaves of the R and S biotypes. By
 using modulated oxygen and heat emissions, and the ratio of
 the initial inflection point (I) to the fluorescence maximum
 (P) as herbicide bioassay indicators, we showed that the
 photoacoustic spectroscopy was also a reliable technique for
 whole plant studies. Inhibition of photosynthesis was maximal
 2 d after onset of treatment with atrazine (200 micromole).
 Inhibitors of PSII did not induce a significant increase of
 heat emission in leaves which otherwise showed phytotoxic
 symptoms after treatment. By using the photoacoustic
 technique, it was possible to obtain useful information on
 photosynthetic activity under herbicide stress, suggesting
 that pulsed oxygen emitted by leaves could be used to quantify
 susceptibility or to detect resistance to many types of
 photosynthetic inhibitors in weeds and crop plants.
 
 
 239                                   NAL Call. No.: 450 P692
 Physiological basis for differential sensitivities of plant
 species to protoporphyrinogen oxidase-inhibiting herbicides.
 Sherman, T.D.; Becerril, J.M.; Matsumoto, H.; Duke, M.V.;
 Jacobs, J.M.; Jacobs, N.J.; Duke, S.O.
 Rockville, Md. : American Society of Plant Physiologists; 1991
 Sep. Plant physiology v. 97 (1): p. 280-287; 1991 Sep. 
 Includes references.
 
 Language:  English
 
 Descriptors: Abutilon theophrasti; Cucumis sativus; Brassica
 hirta; Chenopodium album; Amaranthus retroflexus; Medicago
 sativa; Fagopyrum tataricum; Ipomoea lacunosa; Cassia
 obtusifolia; Datura stramonium; Spinacia oleracea; Herbicide
 resistance; Porphyrins; Biosynthesis; Acifluorfen;
 Phytotoxicity; Weed control; Herbicidal properties
 
 Abstract:  With a leaf disc assay, 11 species were tested for
 effects of the herbicide acifluorfen on porphyrin accumulation
 in darkness and subsequent electrolyte leakage and
 photobleaching of chlorophyll after exposure to light.
 Protoporphyrin IX (Proto IX) was the only porphyrin that was
 substantially increased by the herbicide in any of the
 species. However, there was a wide range in the amount of
 Proto IX accumulation caused by 0.1 millimolar acifluorfen
 between species. Within species, there was a reduced effect of
 the herbicide in older tissues. Therefore, direct quantitative
 comparisons between species are difficult. Nevertheless, when
 data from different species and from tissues of different age
 within a species were plotted, there was a curvilinear
 relationship between the amount of Proto IX caused to
 accumulate during 20 hours of darkness and the amount of
 electrolyte leakage or chlorophyll photobleaching caused after
 6 and 24 hours of light respectively, following the dark
 period. Herbicidal damage plateaued at about 10 nanomoles of
 Proto IX per gram of fresh weight. Little difference was found
 between in vitro acifluorfen inhibition of protoporphyrinogen
 oxidase (Protox) of plastid preparations of mustard, cucumber,
 and morning glory, three species with large differences in
 their susceptibility at the tissue level. Mustard, a highly
 tolerant species, produced little Proto IX in response to the
 herbicide, despite having a highly susceptible Protox.
 Acifluorfen blocked carbon flow from delta-aminolevulinic acid
 to protochlorophyllide in mustard, indicating that it inhibits
 Protox in vivo. Increasing delta-aminolevulinic acid
 concentrations (33-333 micromolar) supplied to mustard with
 0.1 millimolar acifluorfen increased Proto IX accumulation and
 herbicidal activity, demonstrating that mustard sensitivity to
 Proto IX was similar to other species. Differential
 susceptibility to acifluorfen of the species examined in this
 study appears to be due in large part to differences in Proto
 IX accumulation in response to the herbicide.  In some cases,
 differences in Proto IX accumlation appear to be due to
 differences in activity of the porphyrin pathway.
 
 
 240                                   NAL Call. No.: 79.8 W41
 Phytoene desaturase, the essential target for bleaching
 herbicides. Sandmann, G.; Schmidt, A.; Linden, H.; Boger, P.
 Champaign, Ill. : Weed Science Society of America; 1991 Jul.
 Weed science v. 39 (3): p. 474-479; 1991 Jul.  Paper presented
 at the "Symposium on Herbicide Mechanism of Action," February
 7, 1990, Montreal, Canada.  Includes references.
 
 Language:  English
 
 Descriptors: Fluridone; Norflurazon; Flurtamone; Herbicides;
 Mode of action; Herbicidal properties; Enzyme inhibitors;
 Phytoene; Biosynthesis; Biochemical pathways; Herbicide
 resistance; Molecular genetics; Genes; Cyanobacteria; Cloning;
 Mutants
 
 Abstract:  Many bleaching herbicides with different core
 structures inhibit phytoene desaturase (PD), a membrane-bound
 enzyme in the carotenogenic pathway catalyzing the hydrogen
 abstraction step at the first C40 precursor of beta-carotene.
 Prospects are good that new PD-active herbicides will be
 discovered by screening for bleaching activity. Accordingly,
 interest in PD enzymology and molecular genetics has
 increased. Although active carotenogenic cell-free systems are
 available, no isolation of PD has been achieved since the
 enzyme cannot be detected in its isolated form due to complete
 loss of activity. A portion of the Rhodobacter PD gene was
 incorporated into an appropriate plasmid which could be
 expressed in E. coli. This system was used to produce an
 antibody specific against PD from higher plants as well as
 Rhodobacter. All PDs assayed had an apparent molecular weight
 of 52 to 55 kDa. A Rhodobacter gene probe hybridized with a
 3.1 kbBamHI fragment from Aphanocapsa which allowed us to
 sequence the PD gene from this cyanobacterium. Its DNA
 sequence matched with the apparent molecular weight of the PD
 band in the western blot, and a fusion-gene product was found
 to be immunoreactive with the Rhodobacter PD antibody,
 Anacystis mutants were produced exhibiting cross-resistance
 against nornurazon and fluorochloridone. Apparently, this
 resistance is due to an altered PD with concurrent decrease of
 inhibitor binding affinity. Cloning of the resistant gene into
 the wild type is in progress.
 
 
 241                                   NAL Call. No.: 79.8 W41
 Plant cell and tissue culture techniques for weed science
 research. Smeda, R.J.; Weller, S.C.
 Champaign, Ill. : Weed Science Society of America; 1991 Jul.
 Weed science v. 39 (3): p. 497-504; 1991 Jul.  Paper presented
 at the "Symposium on New Techniques adn Advances in Weed
 Physiology and Molecular Biology," February 6, 1991,
 Louisville, Kentucky.  Includes references.
 
 Language:  English
 
 Descriptors: Weeds; Weed biology; Laboratory methods; Tissue
 culture; Cell culture; Screening; Herbicide resistance;
 Metabolism; Herbicides; Mode of action; Uptake; Translocation;
 In vitro selection
 
 Abstract:  Tissue and cell culture offer weed scientists many
 opportunities to research herbicide effects on plants. This
 review will discuss examples in which plant cells grown in
 vitro have been used to study herbicide action. Plant cell and
 tissue culture have many advantages over the use of whole
 plants; however, several disadvantages that exist are
 discussed. Cell cultures can be established for most plant
 species and provide a relatively homogeneous system for
 studying herbicide action. Responses of plant cells to
 herbicides are usually correlated with responses at the whole
 plant level, and cells have the advantage of posing fewer
 physical barriers to herbicide uptake and translocation. Cell
 culture techniques discussed include: screening candidate
 herbicide compounds; investigating herbicide efficacy,
 mechanism of action, metabolism, and uptake; and ascertaining
 mechanisms of herbicide resistance, selecting for resistance,
 and regenerating crops.
 
 
 242                                  NAL Call. No.: QK725.P54
 A plant selectable marker gene based on the detoxification of
 the herbicide dalapon.
 Buchanan-Wollaston, V.; Snape, A.; Cannon, F.
 Berlin, W. Ger. : Springer International; 1992.
 Plant cell reports v. 11 (12): p. 627-631; 1992.  Includes
 references.
 
 Language:  English
 
 Descriptors: Nicotiana plumbaginifolia; Leaves; Agrobacterium
 tumefaciens; Genetic transformation; Gene transfer; Marker
 genes; Selective breeding; Dalapon; Herbicide resistance;
 Phytotoxicity; Enzymes; Degradation; Plasmids; Pseudomonas
 putida
 
 Abstract:  A gene from Pseudomonas putida coding for a
 dehalogenase capable of degrading 2,2 dichloropropionic acid
 (2,2DCPA). the active ingredient of the herbicide dalapon, has
 been isolated and characterised. In plant transformation
 experiments the gene was shown to confer resistance to 2,2DCPA
 at a tissue culture level where 2,2DCPA could be used to
 select for transformants. At the whole plant level,
 transformed plants showed resistance to 2,2DCPA at
 concentrations up to 5 times the recommended dose rate of
 dalapon when it was sprayed on their leaves. At lower
 concentrations, the herbicide caused a non-lethal yellowing of
 sensitive plants which clearly distinguished them from
 resistant plants. The mode of action of chlorinated aliphatic
 acids is not known but they probably affect many enzyme
 pathways. The results described here are the first example of
 engineering a plant resistant to a herbicide that does not
 have one specific enzyme as its target site. This gene has
 several advantages as a marker in plant breeding and genetic
 studies. For example, the herbicide is readily available and
 has low toxicity, transformants can be selected at both the
 tissue culture and the whole plant level, a large number of
 transformed plants can easily be screened even in the field,
 and there is a very low probability of selecting spontaneous
 mutants.
 
 
 243                                   NAL Call. No.: 450 P692
 Pleiotropy in triazine-resistant Brassica napus. Ontogenetic
 and diurnal influences on photosynthesis.
 Dekker, J.H.; Burmester, R.G.
 Rockville, MD : American Society of Plant Physiologists, 1926-
 ; 1992 Dec. Plant physiology v. 100 (4): p. 2052-2058; 1992
 Dec.  Includes references.
 
 Language:  English
 
 Descriptors: Brassica napus; Pleiotropy; Mutations; Structural
 genes; Herbicide resistance; Triazine herbicides;
 Photosynthesis; Chloroplast genetics; Diurnal variation; Crop
 growth stage; Biotypes
 
 Abstract:  Studies were conducted that supported the
 hypothesis that the mutation to the psbA plastid gene that
 confers S-triazine resistance (R) in Brassica napus also
 results in an altered diurnal pattern of photosynthetic carbon
 assimilation (A) relative to that of the susceptible (S) wild
 type, and that these patterns change over the ontogeny of a
 plant. Photosynthetic photon flux density, under closely
 controlled environmental conditions, was incrementally
 increased and decreased on either side of the midday maxima of
 1150 to 1300 micromoles quanta m-2 s-1. In all experiments, A
 approximately tracked the increasing and decreasing diurnal
 light levels. Younger (3- to 4-leaf) R plants had greater
 photosynthetic rates early and late in the diurnal light
 period, whereas those of S plants were greater during midday
 as well as during the photoperiod as a whole. These relative
 photosynthetic characteristics of R and S plants changed in
 several ways with ontogeny. As the plants aged during the
 vegetative phase of development, S plants gradually
 assimilated more carbon in the early, and then in the late,
 part of the day. At the end of the vegetative phase of
 development, R plant carbon assimilation was less relative to
 S plants at most times of the day, and was never greater. This
 relationship between the two biotypes dramatically changed
 with the onset of the reproductive phase (8 1/2 to 9 1/2 leaf)
 of plant development: R plants assimilated more carbon than S
 plants during all periods of the diurnal light period with the
 exception of the late part of the day. In addition to these
 differences in A, R plant stomatal function differed from that
 in S plants. R plant leaves were always cooler than S plant
 leaves under the same environmental and diurnal conditions.
 Correlated with this difference in leaf temperature were equal
 or greater total conductances to water vapor and intercellular
 CO2 partial pressures in R compared to S leaves in most
 instances. These studies indicate a more complex pattern of
 photosynthetic carbon assimilation than previously observed.
 The photosynthetic superiority of one biotype relative to the
 other was a function of the time of day and the age of the
 plant. These studies also suggest that R plants may have an
 adaptive advantage over S plants in certain unfavorable
 ecological niches independent of the presence of S-triazine
 herbicides, such as cool, low-light environments early and
 late in the day, as well as late in the plants' development.
 This advantage could result in R biotypes appearing in
 populations of a species in greater numbers than plastidic
 mutation alone could cause.
 
 
 244                                   NAL Call. No.: 450 P692
 Pollen expression of herbicide target site resistance genes in
 annual ryegrass (Lolium rigidum).
 Richter, J.; Powles, S.B.
 Rockville, MD : American Society of Plant Physiologists, 1926-
 ; 1993 Jul. Plant physiology v. 102(3): p. 1037-1041; 1993
 Jul.  Includes references.
 
 Language:  English
 
 Descriptors: Lolium rigidum; Herbicide resistant weeds;
 Herbicide resistance; Sulfometuron; Triasulfuron; Imazapyr;
 Diclofop; Haloxyfop; Sethoxydim; Pollen; Screening; Gene
 expression; Structural genes; Oxo-acid-lyases; Acetyl-coa
 carboxylase; Bitypes; Pollen germination
 
 Abstract:  Herbicide resistance can occur either through
 target-site insensitivity or by nontarget site-based
 mechanisms. Two herbicide-resistant biotypes of Lolium rigidum
 Gaud., one resistant to acetolactate synthase (ALS)-inhibiting
 herbicides (biotype WLR1) and the other resistant to acetyl
 CoA carboxylase (ACCase)-inhibiting herbicides (biotype WLR96)
 through target-site insensitivity at the whole plant and
 enzymic levels, were found to express this resistance in the
 pollen. Pollen produced by resistant biotypes grew uninhibited
 when challenged with herbicide, whereas that from a
 susceptible biotype was inhibited. A third biotype, SLR31,
 resistant to ACCase-inhibiting and certain ALS-inhibiting
 herbicides at the whole plant level through nontarget site-
 based mechanisms, did not exhibit this expression in the
 pollen. The technique described may form the basis for a rapid
 screen for certain nuclear-encoded, target site-based
 herbicide-resistance mechanisms.
 
 
 245                                 NAL Call. No.: SB317.5.H6
 Potential benefits and risks of herbicide-resistant crops
 produced by biotechnology.
 Dyer, W.E.; Hess, F.D.; Holt, J.S.; Duke, S.O.
 New York, NY : John Wiley & Sons, Inc. Press; 1993.
 Horticultural reviews v. 15: p. 367-408; 1993.  Includes
 references.
 
 Language:  English
 
 Descriptors: Herbicide resistance; Crops; Biotechnology;
 Detoxification; Selection; Screening; Hybridization; Gene
 transfer; Environmental protection; Economic impact; Reviews
 
 
 246                                   NAL Call. No.: 100 T31P
 'Prairie' buffalograss response to selected pre-and post-
 emergence herbicides--update.
 Marcum, K.B.; Engelke, M.C.
 College Station, Tex. : The Station; 1992 Sep.
 PR - Texas Agricultural Experiment Station (5002): p. 65-66;
 1992 Sep.  In the series analytic: Texas turfgrass research-
 -1992.
 
 Language:  English
 
 Descriptors: Texas; Buchloe dactyloides; Herbicide resistance;
 Herbicides; Application rates; Crop damage
 
 
 247                                  NAL Call. No.: QH301.N32
 Producing herbicide tolerant populus using genetic
 transformation mediated by Agrobacterium tumefaciens C58: a
 summary of recent research. Riemenschnedier, D.E.; Haissig,
 B.E.
 New York, N.Y. : Plenum Press; 1991.
 NATO ASI series : Series A : Life sciences v. 210: p. 247-263;
 1991.  In the series analytic: Woody plant biotechnology /
 edited by M.R. Ahuja. Proceedings of a Workshop at the
 Institute of Forest Genetics, USDA Forest Service, October
 15-19, 1989, Placerville, California.  Literature review. 
 Includes references.
 
 Language:  English
 
 Descriptors: Populus alba; Populus grandidentata; Crosses;
 Cultivars; Genetic transformation; Glyphosate; Herbicide
 resistance; Agrobacterium tumefaciens; Literature reviews
 
 
 248                                   NAL Call. No.: 442.8 Z8
 Production and characterization of asymmetric somatic hybrids
 between Arabidopsis thaliana and Brassica napus.
 Bauer-Weston, B.; Keller, W.; Webb, J.; Gleddie, S.
 Berlin, W. Ger. : Springer International; 1993 Apr.
 Theoretical and applied genetics v. 86 (2/3): p. 150-158; 1993
 Apr.  Includes references.
 
 Language:  English
 
 Descriptors: Arabidopsis thaliana; Brassica napus; Somatic
 hybridization; Intergeneric hybridization; Protoplast fusion;
 X radiation; Gene transfer; In vitro selection; Herbicide
 resistance; Chlorsulfuron; Hybrids; Plant morphology; Plant
 breeding
 
 Abstract:  Cell suspension-derived protoplasts of a
 chlorsulfuron-resistant (GH50) strain of Arabidopsis thaliana
 cv Columbia were X-irradiated at 60 or 90 krad, to facilitate
 the elimination of GH50 donor chromosomes in fusion products.
 Irradiated GH50 protoplasts were fused, with polyethylene
 glycol, to protoplasts derived from stem epidermal strips of
 Brassica napus cv Westar. Chlorsulfuron-resistant colonies
 were selected in vitro and then transferred to shoot and root
 regeneration medium. Seventeen hybrid lines were regenerated
 in vitro, and eight were successfully established in the
 greenhouse, where they flowered. These eight asymmetric
 hybrids were intermediate in vegetative morphology between
 Arabidopsis and Brassica. The flowers from these hybrids were
 male-sterile with abnormal petal and pistil structures.
 Zymograms for phosphoglucomutase, esterase, and peroxidase
 showed the presence of all parental isozymes in each of the
 hybrids tested. Nuclear hybridity was also confirmed for the
 ribosomal RNA genes using a wheat rDNA probe; however, the
 chloroplast genome in each of the hybrids was derived solely
 from the Brassica parent. All selected somatic hybrids were
 capable of rooting at levels of chlorsulfuron which were
 inhibitory to unfused Brassica plantlets. The degree of
 herbicide resistance in the hybrid shoots is presently being
 evaluated.
 
 
 249                            NAL Call. No.: S494.5.B563B554
 Promoting crop protection by genetic engineering and
 conventional plant breeding: problems and prospects.
 Woolhouse, H.W.
 Wallingford, Oxford, UK : CAB International; 1992.
 Biotechnology in agriculture v. 7: p. 249-256; 1992.  In the
 series analytic: Plant genetic manipulation for crop
 protection / edited by A.M.R. Gatehouse, V.A. Hilder and
 Boulter, D.
 
 Language:  English
 
 Descriptors: Crops; Genetic engineering; Genetic improvement;
 Plant breeding; Defense mechanisms; Insect control; Varietal
 resistance; Plant viruses; Herbicide resistance; Mixed
 cropping; Gene mapping; Breeding programs
 
 
 250                                 NAL Call. No.: 442.8 IN82
 Properties and uses of photoautotrophic plant cell cultures.
 Widholm, J.M.
 San Diego, Calif. : Academic Press; 1992.
 International review of cytology v. 132: p. 109-175; 1992. 
 Includes references.
 
 Language:  English
 
 Descriptors: Plants; Cell cultures; Growth; Photosynthesis;
 Cell differentiation; Metabolism; Molecular biology; Genetic
 engineering; Herbicide resistance
 
 
 251                                  NAL Call. No.: QH301.N32
 PS II inhibitor binding, Q(B)-mediated electron flow and rapid
 degradation are separable properties of the D1 reaction centre
 protein.
 Jansen, M.A.K.; Driesenaar, A.R.J.; Kless, H.; Malkin, S.;
 Mattoo, A.K.; Edelman, M.
 New York, N.Y. : Plenum Press; 1992.
 NATO ASI series : Series A : Life sciences v. 226: p. 303-311;
 1992.  In the series analytic: Regulation of chloroplast
 biogenesis / edited by J.H. Argyroudi-Akoyunoglou. Proceedings
 of a NATO Advanced Research Workshop, July 28-August 3, 1991,
 Crete, Greece.  Includes references.
 
 Language:  English
 
 Descriptors: Spirodela oligorhiza; Mutants; Herbicide
 resistance; Light; Photosystem ii; Plant proteins;
 Biodegradation; Cytochromes; Electron transfer
 
 
 252                                   NAL Call. No.: 450 P693
 Purification and properties of a glyphosate-tolerant 5-
 enolpyruvylshikimate 3-phosphate synthase from the
 cyanobacterium Anabaena variabilis. Powell, H.A.; Kerby N.W.;
 Rowell, P.; Mousdale, D.M.; Coggins, J.R. Berlin : Springer-
 Verlag; 1992.
 Planta v. 188 (4): p. 484-490; 1992.  Includes references.
 
 Language:  English
 
 Descriptors: Anabaena variabilis; Alkyl (aryl) transferases;
 Purification; Enzyme activity; Glyphosate; Herbicide
 resistance; Tolerance
 
 Abstract:  5-Enolpyruvylshikimate 3-phosphate (EPSP) synthase
 (3-phosphoshikimate 1-carboxyvinyltransferase; EC 2.5.1.9)
 from the glyphosate-tolerant cyanobacterium Anabaena
 variabilis (ATCC 29413) was purified to homogeneity. The
 enzyme had a similar relative molecular mass to other EPSP
 synthases and showed similar kinetic properties except for a
 greatly elevated K(i) for the herbicide glyphosate
 (approximately ten times higher than that of enzymes from
 other sources). With whole cells, the monoisopropylamine salt
 of glyphosate was more toxic than the free acid but the
 effects of the free acid and monoisopropylamine salt on
 purified EPSP synthase were identical.
 
 
 253                                     NAL Call. No.: S51.E2
 Purple nutsedge control with imazaquin in bermudagrass turf.
 Johnson, B.J.; Murphy, T.R.
 Athens, Ga. : The Stations; 1992 Feb.
 Research bulletin - University of Georgia, Agricultural
 Experiment Stations (408): 12 p.; 1992 Feb.  Includes
 references.
 
 Language:  English
 
 Descriptors: Georgia; Cynodon dactylon; Cyperus rotundus;
 Imazaquin; Lawns and turf; Weed control; Field tests;
 Herbicides; Herbicide resistance
 
 
 254                                   NAL Call. No.: 100 F663
 Pursuit: advantages and disadvantage in lettuce production.
 Dusky, J.A.; Al-Henaid, J.
 Belle Glade, Fla. : The Center; 1993 Feb.
 Belle Glade EREC research report EV - Florida University
 Agricultural Research and Education Center (1993-2): p.
 127-132; 1993 Feb.  Paper presented at the Lettuce Research
 Workshop, February 4, 1993, Belle Glade, Florida.
 
 Language:  English
 
 Descriptors: Florida; Lactuca sativa; Imazethapyr; Weed
 control; Amaranthus spinosus; Amaranthus lividus; Herbicide
 resistance; Application rates; Bioassays; Soil analysis;
 Rotations; Application date; Crop yield
 
 
 255                                  NAL Call. No.: SB951.P49
 Pyridate is not a two-site inhibitor, and may be more prone to
 evolution of resistance than other phenolic herbicides.
 Gressel, J.; Evron, Y.
 Orlando, Fla. : Academic Press; 1992 Oct.
 Pesticide biochemistry and physiology v. 44 (2): p. 140-146;
 1992 Oct. Includes references.
 
 Language:  English
 
 Descriptors: Lactuca sativa; Pyridate; Mode of action;
 Pharmacodynamics; Photosynthesis; Herbicide resistance;
 Photosystem ii; Inhibitors; Binding site
 
 Abstract:  Target site resistance has evolved to only those
 herbicides affecting a single system. Extensive resistance has
 evolved to photosystem II inhibitors, especially atrazine, but
 not to the phenolic-type herbicides (e.g., dinoseb), which
 both affect photosystem II and purportedly uncouple
 mitochondrial phosphorylation and photophosphorylation.
 Pyridate, which has been classified as a "phenolic"-type
 herbicide, is highly effective in controlling triazine-
 resistant weeds. We demonstrate here that the active de-S-
 octyl derivative of pyridate does not have this second target
 site; photophosphorylation was only affected at 100 times
 greater concentration than photosystem II activity. From this
 point of view, pyridate may be more prone to evolution of
 resistance than phenolic-type herbicides with two sites of
 action.
 
 
 256                                   NAL Call. No.: 23 AU783
 Radiometry accurately measures chlorsulfuron injury to barley.
 Lemerle, D.; Fisher, J.A.; Hinkley, R.B.
 Melbourne : Commonwealth Scientific and Industrial Research
 Organization; 1993.
 Australian journal of agricultural research v. 44 (1): p.
 13-21; 1993. Includes references.
 
 Language:  English
 
 Descriptors: New South Wales; Hordeum vulgare; Cultivars; Crop
 damage; Herbicide resistance; Phytotoxicity; Chlorsulfuron
 
 
 257                                  NAL Call. No.: QK710.P63
 A rapid assay for chloroplast-encoded triazine resistance in
 higher plants. Cheung, W.Y.; Cote, J.C.; Benoit, D.L.; Landry,
 B.S.
 Athens, Ga. : International Society for Plant Molecular
 Biology, University of Georgia; 1993 Jun.
 Plant molecular biology reporter - ISPMB v. 11 (2): p.
 142-155; 1993 Jun. Includes references.
 
 Language:  English
 
 Descriptors: Plant breeding; Genetic analysis; Chloroplasts;
 Genetic code; Triazine herbicides; Herbicide resistance;
 Laboratory methods; Rapid methods; Polymerase chain reaction;
 Dna amplification
 
 
 258                                  NAL Call. No.: SB610.W39
 Rapid diagnosis of ALS/AHAS-resistant weeds.
 Gerwick, B.C.; Mireles, L.C.; Eilers, R.J.
 Champaign, Ill. : The Weed Science Society of America; 1993
 Apr. Weed technology : a journal of the Weed Science Society
 of America v. 7 (2): p. 519-524; 1993 Apr.  Includes
 references.
 
 Language:  English
 
 Descriptors: Herbicide resistant weeds; Biotypes; Detection;
 Assays; Herbicide resistance; Mode of action; Ligases; Enzyme
 inhibitors; Imazaquin; Abutilon theophrasti; Xanthium
 strumarium; Amaranthus retroflexus; Chenopodium album; Sorghum
 bicolor; Isomerases; Acetoin; Plant composition
 
 
 259                                   NAL Call. No.: 79.8 W41
 Rapid germination of sulfonylurea-resistant Kochia seoparia L.
 accessions is associated with elevated seed levels of branched
 chain amino acids. Dyer, W.E.; Chee, P.W.; Fay, P.K.
 Champaign, Ill. : Weed Science Society of America; 1993 Jan.
 Weed science v. 41 (1): p. 18-22; 1993 Jan.  Includes
 references.
 
 Language:  English
 
 Descriptors: Kochia scoparia; Herbicide resistance;
 Susceptibility; Sulfonylurea herbicides; Seed germination;
 Soil temperature; Free amino acids; Isoleucine; Valine;
 Leucine; Enzymes; Enzyme activity
 
 Abstract:  Field observations indicate that sulfonylurea-
 resistant kochia may germinate at lower soil temperatures
 and/or germinate more rapidly than susceptible kochia in the
 absence of herbicide. To investigate this possibility, seeds
 from three resistant and two susceptible kochia accessions
 were germinated at temperatures ranging from 4.6 to 13.2
 degrees C on thermal gradient plates. At 4.6 and 13.2 degrees
 C, germination rates of all resistant accessions were higher
 than susceptible accessions, while germination rates of one
 resistant accession were higher than susceptible accessions at
 7.2 and 10.5 degrees C. Percent germination of all resistant
 accessions was significantly higher than susceptible
 accessions after 48 h at 4.6 degrees C. At higher
 temperatures, percent germination of some resistant accessions
 was higher after 12 or 24 h, but germination of all accessions
 was similar at later times. HPLC analysis revealed that seeds
 from resistant accessions contained about 2-fold higher free
 levels of branched chain amino acids than seeds from
 susceptible accessions. The results indicate that mutations
 conferring resistance to sulfonylurea herbicides in these
 kochia accessions may concomitantly reduce or abolish
 acetolactate synthase sensitivity to normal feedback
 inhibition patterns, resulting in elevated levels of branched
 chain amino acids available for cell division and growth
 during early germination.
 
 
 260                                  NAL Call. No.: SB951.P49
 Rapid metabolic inactivation is the basis for cross-resistance
 to chlorsulfuron in diclofop-methyl-resistant rigid ryegrass
 (Lolium rigidum) biotype SR4/84.
 Cotterman, J.C.; Saari, L.L.
 Orlando, Fla. : Academic Press; 1992 Jul.
 Pesticide biochemistry and physiology v. 43 (3): p. 182-192;
 1992 Jul. Includes references.
 
 Language:  English
 
 Descriptors: Lolium rigidum; Biotypes; Herbicide resistant
 weeds; Herbicide resistance; Diclofop; Cross resistance;
 Chlorsulfuron; Metabolism; Metabolic detoxification;
 Pharmacokinetics; Oxo-acid-lyases; Enzyme activity;
 Metabolites
 
 Abstract:  Experiments were conducted to determine the
 mechanism of cross-resistance to chlorsulfuron
 (2-chloro-N-[[(4-methoxy-6-methyl-1,3,5-triazin-2-
 yl)amino]carbonyl] benzenesulfonamide) in diclofop-methyl
 (methyl
 (+/-)-2-[4-(2,4-dichlorophenoxy)phenoxy]propanoic acid)-
 resistant rigid ryegrass (Lolium rigidum Gaudin). In excised
 shoots and roots, [14C]chlorsulfuron was metabolized with a
 half-life of 1 and 3 hr, respectively, in the resistant
 biotype (SR4/84) versus 4 and 13 hr respectively, in the
 susceptible biotype (SRS2). Based on coelution with standards
 in high performance liquid chromatography (HPLC) and treatment
 with beta-glucosidase followed by HPLC, the major
 chlorsulfuron metabolite in shoots and roots of both biotypes
 was identified as the herbicidally-inactive glucose conjugate
 of hydroxy-chlorsulfuron. Acetolactate synthase (ALS, the
 target enzyme of chlorsulfuron) isolated from both biotypes
 was inhibited to the same degree by chlorsulfuron. The glucose
 conjugate of hydroxy-chlorsulfuron was inactive at the enzyme
 level, as it required greater than or equal to 36-fold higher
 concentrations compared to chlorsulfuron to inhibit the ALS
 from both biotypes. When [14C]chlorsulfuron was applied to the
 leaf surface, approximately 50% was absorbed within 48 hr by
 both biotypes. Of the radioactivity absorbed, less than 10%
 was translocated out of the treated leaf in either biotype.
 Based on these results, chlorsulfuron resistance in SR4/84 is
 due to enhanced metabolic inactivation of the herbicide,
 specifically to the glucose conjugate, compared to the
 sensitive biotype. Resistance is not due to reduced
 sensitivity of ALS or increased uptake or translocation in
 SR4/84.
 
 
 261                                   NAL Call. No.: QH442.B5
 Rapid production of transgenic wheat plants by direct
 bombardment of cultured immature embryos.
 Vasil, V.; Srivastava, V.; Castillo, A.M.; Fromm, M.E.; Vasil,
 I.K. New York, N.Y. : Nature Publishing,; 1993 Dec.
 Bio/technology v. 11 (13): p. 1553-1558; 1993 Dec.  Includes
 references.
 
 Language:  English
 
 Descriptors: Triticum aestivum; Genetic transformation; Plant
 embryos; Transgenic plants; Reporter genes; Beta-
 glucuronidase; Acyltransferases; Herbicide resistance; Plasmid
 vectors; Inheritance; Segregation; Glufosinate; Callus;
 Embryogenesis; In vitro selection
 
 
 262                                  NAL Call. No.: SB610.W39
 Rationale for developing herbicide-resistant crops.
 Burnside, O.C.
 Champaign, Ill. : The Society; 1992 Jul.
 Weed technology : a journal of the Weed Science Society of
 America v. 6 (3): p. 621-625; 1992 Jul.  Paper presented at
 the Symposium, "Development of Herbicide-Resistant Crop
 Cultivars", Weed Science Society of America, February 6, 1991,
 Louisville, Kentucky.  Includes references.
 
 Language:  English
 
 Descriptors: Transgenic plants; Crops; Herbicide resistance;
 Genotypes; Biotechnology; Weed control; Risk
 
 
 263                                  NAL Call. No.: 64.8 C883
 Recurrent selection for glyphosate tolerance in birdsfoot
 trefoil. Boerboom, C.M.; Ehlke, N.J.; Wyse, D.L.; Somers, D.A.
 Madison, Wis. : Crop Science Society of America; 1991 Sep.
 Crop science v. 31 (5): p. 1124-1129; 1991 Sep.  Includes
 references.
 
 Language:  English
 
 Descriptors: Lotus corniculatus; Weed control; Cirsium
 arvense; Chemical control; Glyphosate; Herbicide resistance;
 Selection criteria; Recurrent selection; Enzyme activity;
 Ligases
 
 Abstract:  Glyphosate [N-(phosphonomethyl)glycine] tolerant
 birdsfoot trefoil (Lotus corniculatus L.) would allow
 selective herbicide control of Canada thistle [Cirsium arvense
 (L.) Scop.] and other dicot weeds in seed production fields.
 The objectives of this research were to determine if recurrent
 selection can increase the level of glyphosate tolerance in
 birdsfoot trefoil and if increased glyphosate tolerance is
 associated with increased 5-enolpyruvylshikimate 3-phosphate
 (EPSP) synthase activity. Two cycles of selection for
 glyphosate tolerance were made in three birdsfoot trefoil
 germplasms, Leo', Norcen', and MU-81' by selecting seedlings
 following treatment with 0.56 kg ae/ha (kg acid equivalents
 per hectare) of glyphosate. To evaluate tolerance, seedings
 with eight leaves of the selected and parental populations
 were either untreated or treated with 0.56 kg ae/ha of
 glyphosate plus surfactant in a greenhouse. Shoot fresh
 weights were measured 14 days after treatment (DAT) and
 regrowth was measured 35 DAT. Treated shoot weights of the
 three C2 populations were from 44 to 85% greater than their C0
 populations, indicating increased glyphosate tolerance. The
 evaluation of regrowth weights also showed 44 to 127%
 increases in the C0 populations. Tolerant plants from C2
 populations had greater EPSP synthase-specific activity (the
 primary site of action of glyphosate) than susceptible C0
 plants. This suggested that tolerance was at least partially
 conferred by increased EPSP synthase activity. Genetic
 variance should allow continued progress from selection for
 increased glyphosate tolerance in birdsfoot trefoil.
 
 
 264                                  NAL Call. No.: QK725.P54
 Regeneration of herbicide resistant transgenic rice plants
 following microprojectile-mediated transformation of
 suspension culture cells. Cao, J.; Duan, X.L.; McElroy, D.;
 Wu, R.
 Berlin, W. Ger. : Springer International; 1992.
 Plant cell reports v. 11 (11): p. 586-591; 1992.  Includes
 references.
 
 Language:  English
 
 Descriptors: Oryza sativa; Cell suspensions; Genetic
 transformation; Dna; Gene transfer; Plasmids; Herbicide
 resistance; Glufosinate; Gene expression; Selection; Gene
 mapping; Nucleotide sequences
 
 Abstract:  Suspension cells of Oryza sativa L. (rice) were
 transformed, by microprojectile bombardment, with plasmids
 carrying the coding region of the Streptomyces hygroscopicus
 phosphinothricin acetyl transferase (PAT) gene (bar) under the
 control of either the 5' region of the rice actin 1 gene
 (Act1) or the cauliflower mosaic virus (CaMV) 35S promoter.
 Subsequently regenerated plants display detectable PAT
 activity and are resistant to BASTA, a phosphinothricin (PPT)-
 based herbicide. DNA gel blot analyses showed that PPT
 resistant rice plants contain a bar-hybridizing restriction
 fragment of the expected size. This report shows that
 expression of the bar gene in transgenic rice plants confers
 resistance to PPT-based herbicide by suppressing an increase
 of ammonia in plants after spraying with the herbicide.
 
 
 265                           NAL Call. No.: QK882.P5577 1993
 Regulation of electron transport at the acceptor side of
 photosystem II by herbicides, bicarbonate and formate.
 Rensen, J.S. van
 Dordrecht : Kluwer Academic Publishers; 1993.
 Photosynthesis : photoreactions to plant productivity / edited
 by Yash Pal Abrol, Prasanna Mohanty, Govindjee. p. 157-180;
 1993.  Literature review. Includes references.
 
 Language:  English
 
 Descriptors: Photosynthesis; Photosystem ii; Electron
 transfer; Quinones; Herbicides; Herbicidal properties; Formic
 acid; Organic anions; Carbon; Anions; Herbicide resistance;
 Binding site; Literature reviews; Plant proteins
 
 Abstract:  The photosystem II reaction center can be
 considered as a water-plastoquinone oxido-reductase. Using
 four photons it transfers four electrons from two molecules of
 water to plastoquinone producing molecular oxygen and two
 molecules of doubly reduced plastoquinone. Our understanding
 of the structure and function of this complex has greatly
 increased during the recent years. The basis of the reaction
 center of photosystem II is formed by the D1 and D2 proteins,
 both having a molecular mass of about 32 kDa. The D1 protein
 contains not only the binding site for the physiological
 electron carrier QB, but also the binding sites for several
 classes of herbicides and for bicarbonate and formate. Both
 the diuron-type and the phenol-type herbicides act by
 replacing the physiological electron carrier QB from its
 binding site at the D1 protein. Because the herbicides cannot
 be reduced, the electron flow is interrupted between the
 primary electron acceptor of photosystem II QA, and the
 plastoquinone pool. There appears a relation between the
 residence time of a herbicide at the D1 protein and its
 activity as an inhibitor of electron flow. Incubation of
 isolated chloroplasts with formate, while flushing them with
 nitrogen gas, results in full inhibition of electron flow
 activity, which can be restored by addition of bicarbonate.
 This antagonistic action of formate and bicarbonate is located
 at the D1 protein and affects electron flow between QA and the
 plastoquinone pool. The advances in this field should
 encourage future work on the mechanism of the action of
 formate and bicarbonate at the molecular level as well as on
 their action in vivo. The study of triazine-resistance in
 weeds and herbicide-resistance in algae and photosynthetic
 bacteria has resulted in the recognition of a common binding
 niche for QB, herbicides, formate and bicarbonate at the D1
 protein including the hydrophobic transmembrane helices IV and
 V and the parallel helix connecting these on the matrix side
 of the D1 protein.
 
 
 266                                   NAL Call. No.: 450 P692
 Regulation of photosynthesis in trizaine-resistant and -
 susceptible Brassica napus.
 Dekker, J.H.; Sharkey, T.D.
 Rockville, Md. : American Society of Plant Physiologists; 1992
 Mar. Plant physiology v. 98 (3): p. 1069-1073; 1992 Mar. 
 Includes references.
 
 Language:  English
 
 Descriptors: Brassica napus; Photosynthesis; Regulation;
 Triazines; Net assimilation rate; Chlorophyll; Fluorescence;
 Temperature; Biotypes; Herbicide resistance
 
 Abstract:  The response of photosynthetic carbon assimilation
 and chlorophyll fluorescence quenching to changes in
 intercellular CO2 partial pressure (C(i)), O2 partial
 pressure, and leaf temperature (15-35 degrees C) in triazine-
 resistant and -susceptible biotypes of Brassica napus were
 examined to determine the effects of the changes in the
 resistant biotype on the overall process of photosynthesis in
 intact leaves. Three categories of photosynthetic regulation
 were observed. The first category of photosynthetic response,
 ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco)-
 limited photosynthesis, was observed at 15, 25, and 35 degrees
 C leaf temperatures with low C(i). When the carbon
 assimilation rate was Rubisco-limited, there was little
 difference between the resistant and susceptible biotypes, and
 Rubisco activity parameters were similar between the two
 biotypes. A second category, called feedback-limited
 photosynthesis, was evident at 15 and 25 degrees C above 300
 microbars C(i). The third category, photosynthetic electron
 transport-limited photosynthesis, was evident at 25 and 35
 degrees C at moderate to high CO2. At low temperature, when
 the response curves of carbon assimilation to C(i) indicated
 little or no electron transport limitation, the carbon
 assimilation rate was similar in the resistant and susceptible
 biotypes. With increasing temperature, more electron
 transport-limited carbon assimilation was observed, and a
 greater difference between resistant and susceptible biotypes
 was observed. These observations reveal the increasing
 importance of photosynthetic electron transport in controlling
 the overall rate of photosynthesis in the resistant biotype as
 temperature increases. Photochemical quenching of chlorophyll
 fluorescence (q(p)) in the resistant biotype never exceeded
 60%, and triazine resistance effects were more evident when
 the susceptible biotype had greater than 60% q(p), but not
 when it had less than 60% q(p).
 
 
 267                                   NAL Call. No.: 79.8 W41
 Relationship of leaf surface characteristics to acifluorfen
 tolerance in tomato (Lycopersicon esculentum) and related
 species.
 Ricotta, J.A.; Masiunas, J.B.
 Champaign, Ill. : Weed Science Society of America; 1992 Jul.
 Weed science v. 40 (3): p. 402-407; 1992 Jul.  Includes
 references.
 
 Language:  English
 
 Descriptors: Lycopersicon esculentum; Weed control; Solanum;
 Genotypes; Herbicide resistance; Screening; Acifluorfen;
 Leaves; Cuticle; Waxes; Trichomes; Density; Stomata
 
 Abstract:  Fourteen tomato genotypes, eastern black
 nightshade, and 35 Lycopersicon accessions were screened for
 tolerance to acifluorfen. Tolerant and susceptible genotypes
 occurred in most species. Fifteen genotypes were chosen for
 further study depending on their fresh weight after
 acifluorfen treatment. Over all 15 genotypes, there was no
 correlation between trichome density and acifluorfen
 tolerance; however, in L. esculentum, cultivars with the most
 trichomes were the most tolerant. There was an inverse
 relationship between stomata density and tolerance. Amount and
 composition of epicuticular wax and cuticle thickness did not
 correlate to acifluorfen tolerance.
 
 
 268                                   NAL Call. No.: 450 P693
 Relationships among the herbicide and functional sites of
 acetohydroxy acid synthase from Chlorella emersonii.
 Landstein, D.; Arad, S.M.; Barak, Z.; Chipman, D.M.
 Berlin ; New York : Springer-Verlag, 1925-; 1993.
 Planta v. 191 (1): p. 1-6; 1993.  Includes references.
 
 Language:  English
 
 Descriptors: Chlorella; Oxo-acid-lyases; Enzyme activity;
 Inhibition; Sulfometuron; Mutants; Herbicide resistance;
 Anilide herbicides; Imidazolinone herbicides; Binding site;
 Amino acid sequences
 
 Abstract:  The properties of acetohydroxy acid synthase (AHAS,
 EC 4.1.3.18) from wild-type Chlorella emersonii (var.
 Emersonii, CCAP-211/11n) and two spontaneous sulfometuron
 methyl (SMM)-resistant mutants were examined. The AHAS from
 both mutants was resistant to SMM and cross-resistant to
 imazapyr (IM) and the triazolopyrimidine sulfonanilide
 herbicide XRD-498 (TP). The more-SMM-resistant mutant had AHAS
 with altered catalytic parameters (Km, specificity), but
 unchanged sensitivity to the feedback inhibitors valine and
 leucine. The second mutant enzyme was less sensitive to the
 feedback inhibitors, but had otherwise unchanged kinetic
 parameters. Inhibition-competition experiments indicated that
 the three herbicides (SMM, IM, TP) bind in a mutually
 exclusive manner, but that valine can bind simultaneously with
 SMM or TP. The three herbicide classes apparently bind to
 closely overlapping sites. We suggest that the results with C.
 emersonii and other organisms can all be explained if there
 are separate binding sites for herbicides, feedback inhibitors
 and substrates.
 
 
 269                                  NAL Call. No.: QH301.A76
 Residual herbicides for newly planted farm woodlands: efficacy
 and tree tolerance.
 Britt, C.P.
 Wellesbourne, Warwick : The Association of Applied Biologists;
 1992. Aspects of applied biology (29): p. 211-218; 1992.  In
 the series analytic: Vegetation management in forestry,
 amenity and conservation areas. Paper presented at the
 conference of the Association, April 7-9, 1992, University of
 York, England.  Includes references.
 
 Language:  English
 
 Descriptors: England; Acer pseudoplatanus; Fraxinus excelsior;
 Prunus avium; Survival; Weed control; Weeds; Farm woodlands;
 Herbicide mixtures; Herbicide residues; Herbicide resistance
 
 
 270                                  NAL Call. No.: SB957.R47
 Resistance of giant foxtail (Setaria faberi Herrm.) and large
 crabgrass [Digitaria sanguinalis (L.) Scop.] biotypes to
 acetyl-coenzyme A carboxylase inhibitors.
 Wiederholt, R.J.; Stoltenberg, D.E.
 East Lansing, Mich. : Pesticide Research Center, Michigan
 State University,; 1993.
 Resistant pest management v. 5 (2): p. 17-18; 1993.
 
 Language:  English
 
 Descriptors: Wisconsin; Cabt; Setaria faberi; Digitaria
 sanguinalis; Biotypes; Herbicide resistant weeds; Herbicide
 resistance; Enzyme inhibitors; Acetyl coenzyme a
 
 
 271                                  NAL Call. No.: SB610.W39
 Resistance of Palmer amaranth (Amaranthus palmeri) to the
 dinitroaniline herbicides.
 Gossett, B.J.; Murdock, E.C.; Toler, J.E.
 Champaign, Ill. : The Society; 1992 Jul.
 Weed technology : a journal of the Weed Science Society of
 America v. 6 (3): p. 587-591; 1992 Jul.  Includes references.
 
 Language:  English
 
 Descriptors: South Carolina; Amaranthus palmeri; Biotypes;
 Trifluralin; Herbicide resistance; Susceptibility; Cross
 resistance; Herbicides; Application rates; Weed control;
 Chemical control
 
 
 272                                  NAL Call. No.: SB610.W39
 Resistance of selected ornamental grasses to graminicides.
 Catanzaro, C.J.; Skroch, W.A.; Burton, J.D.
 Champaign, Ill. : The Weed Science Society of America; 1993
 Apr. Weed technology : a journal of the Weed Science Society
 of America v. 7 (2): p. 326-330; 1993 Apr.  Includes
 references.
 
 Language:  English
 
 Descriptors: Ornamental plants; Panicum virgatum; Festuca
 ovina; Pennisetum alopecuroides; Festuca; Erianthus; Herbicide
 resistance; Fenoxaprop; Fluazifop-p; Quizalofop; Sethoxydim;
 Phytotoxicity
 
 
 273                                   NAL Call. No.: 450 P692
 Resistance to acetolactate synthase-inhibiting herbicides in
 annual ryegrass (Lolium rigidum) involves at least two
 mechanisms.
 Christopher, J.T.; Powles, S.B.; Holtum, J.A.M.
 Rockville, MD : American Society of Plant Physiologists, 1926-
 ; 1992 Dec. Plant physiology v. 100 (4): p. 1909-1913; 1992
 Dec.  Includes references.
 
 Language:  English
 
 Descriptors: Lolium rigidum; Herbicide resistant weeds;
 Chlorsulfuron; Sulfonylurea herbicides; Imidazolinone
 herbicides; Oxo-acid-lyases; Enzyme activity; Cross
 resistance; Diclofop; Herbicidal properties; Metabolism;
 Biotypes
 
 Abstract:  WLR1, a biotype of Lolium rigidum Gaud. that had
 been treated with the sulfonylurea herbicide chlorsulfuron in
 7 consecutive years, was found to be resistant to both the
 wheat-selective and the nonselective sulfonylurea and
 imidazolinone herbicides. Biotype SLR31, which became cross-
 resistant to chlorsulfuron following treatment with the
 aryloxyphenoxypropionate herbicide diciofop-methyl, was
 resistant to the wheat-selective, but not the nonselective,
 sulfonylurea and imidazolinone herbicides. The concentrations
 of herbicide required to reduce in vitro acetolactate synthase
 (ALs) activity 50% with respect to control assays minus
 herbicide for biotype WLR1 was greater than those for
 susceptible biotype VLR1 by a factor of >30, >30, 7, 4, and 2
 for the herbicides chlorsulfuron, sulfometuron-methyl,
 imazapyr, imazathapyr, and imazamethabenz, respectively. ALS
 activity from biotype SLR31 responded in a similar manner to
 that of the susceptible biotype VLR1. The resistant biotypes
 metabolized chlorsulfuron more rapidly than the susceptible
 biotype. Metabolism of 50% of [phenyl-U-14C] chlorsulfuron in
 the culms of two-leaf seedlings required 3.7 h in biotype
 SLR31, 5.1 h in biotype WLR1, and 7.1 h in biotype VLR1. In
 all biotypes the metabolism of chlorsulfuron in the culms was
 more rapid than that in the leaf lamina. Resistance to ALS
 inhibitors in L. rigidum may involve at least two mechanisms,
 increased metabolism of the herbicide and/or a herbicide-
 insensitive ALS.
 
 
 274                                   NAL Call. No.: 79.8 W41
 Resistance to aryloxyphenoxypropionate herbicides in two wild
 oat species (Avena fatua and Avena sterilis ssp. ludoviciana).
 Mansooji, A.M.; Holtum, J.A.; Boutsalis, P.; Matthews, J.M.;
 Powles, S.B. Champaign, Ill. : Weed Science Society of
 America; 1992.
 Weed science v. 40 (4): p. 599-605; 1992.  Includes
 references.
 
 Language:  English
 
 Descriptors: Australia; Avena fatua; Avena sterilis subsp.
 ludoviciana; Herbicide resistant weeds; Herbicide resistance;
 Cross resistance; Diclofop; Biotypes; Fluazifop; Haloxyfop;
 Fenoxaprop; Quizalofop; Propaquizafop; Sethoxydim; Cycloxydim;
 Tralkoxydim
 
 Abstract:  Resistance to the methyl ester of diclofop, an
 aryloxyphenoxypropionate graminicide, was shown for a wild oat
 (Avena fatua) population from Western Australia, and marked
 resistance to a range of aryloxyphenoxypropionate and
 cyclohexanedione graminicides was detected in a winter wild
 oat (Avena sterilis ssp. ludoviciana) population from South
 Australia. The A. sterilis biotype exhibited high levels of
 resistance to the aryloxyphenoxypropionate herbicides
 diclofop, fluazifop, haloxyfop, fenoxaprop, quizalofop,
 propaquizafop, and quinfurop and low levels of resistance to
 the cyclohexanedione herbicides sethoxydim, tralkoxydim, and
 cycloxydim. Ratios of LD50 values for responses of resistant
 and susceptible A. sterilis to the aryloxyphenoxypropionate
 herbicides were between 20 for propaquizafop and > 1,000 for
 fluazifop, and were between 2.5 and 3 for the cyclohexanedione
 herbicides. The LD50 value for diclofop for the A. fatua
 biotype was 442 g ai ha-1 which was 2.7-fold that of a
 susceptible control. Thirty-three percent of the plants
 survived at the registered rate of application.
 
 
 275                                   NAL Call. No.: 450 P692
 Resistance to the herbicide paraquat and increased tolerance
 to photoinhibition are not correlated in several weed species.
 Preston, C.; Holtum, J.A.M.; Powles, S.B.
 Rockville, Md. : American Society of Plant Physiologists; 1991
 May. Plant physiology v. 96 (1): p. 314-318; 1991 May. 
 Includes references.
 
 Language:  English
 
 Descriptors: Australia; Hordeum glaucum; Conyza bonariensis;
 Hordeum murinum subsp. leporinum; Arctotheca calendula;
 Herbicide resistant weeds; Paraquat; Biotypes;
 Photoinhibition; Resistance
 
 Abstract:  Photoinhibition was examined in paraquat-resistant
 and paraquat-susceptible biotypes of Hordeum glaucum Steud.,
 Hordeum leporinum Link., Arctotheca calendula (L.) Levyns.,
 and Conyza bonariensis (L.) Cronq. Plants were photoinhibited
 at low temperature, and the extent of photoinhibition
 determined by O2 evolution and 77 K fluorescence. No
 difference in the degree of photoinhibition was detected
 between paraquat-resistant and paraquat-susceptible biotypes
 for any of the species examined. C. bonariensis plants were
 also photoinhibited by treatment without CO2 at either 21%
 (volume/volume) O2 or 4% (volume/volume) O2, and again no
 difference was observed between the paraquat-resistant and
 paraquat-susceptible biotypes in reduction of the ratio of
 variable fluorescence to maximal fluorescence. This is in
 contrast to a recent report (MAK Jansen, Y Shaaltiel, D
 Kazzes, 0 Canaani, S Malkin, J Gressel, [1989] Plant Physiol
 91: 1174-1178 in which it was claimed that a paraquat-
 resistant biotype of C. bonariensis was more tolerant of
 photoinhibition than a paraquat-susceptible biotype. We
 conclude that paraquat-resistant biotypes of these plant
 species are not more tolerant of photoinhibition when compared
 with the paraquat-susceptible biotypes.
 
 
 276                                  NAL Call. No.: 64.8 C883
 Resistance to the sulfonylurea herbicides chlorsulfuron,
 amidosulfuron, and DPX-R9674 in transgenic flue-cured tobacco.
 Brandle, J.E.; Labbe, H.; Zilkey, B.F.; Miki, B.L.
 Madison, Wis. : Crop Science Society of America; 1992 Jul.
 Crop science v. 32 (4): p. 1049-1053; 1992 Jul.  Includes
 references.
 
 Language:  English
 
 Descriptors: Canada; Nicotiana tabacum; Herbicide resistance;
 Sulfonylurea herbicides; Transgenics; Agrobacterium; Genetic
 transformation; Genotypes; Application rates; Seedlings;
 Treatment; Selection criteria; Gene expression; Genetic
 analysis
 
 Abstract:  Only one herbicide is currently available for
 preemergence broadleaf weed control in flue-cured tobacco
 (Nicotiana tabacum L.) grown in Canada. The high cost of
 registration, coupled with the small crop size, has resulted
 in few new products becoming available. Herbicide resistance
 introduced into tobacco by Agrobacterium-mediated
 transformation formation may allow the use of products with
 existing or impending registrations. We used two new, low-
 residual sulfonylurea herbicides: amidosulfuron (3-(4, 6-
 dimethoxyprymidin-2-yl)-l-(N-methyl-N-methylsulfonyl-
 aminosulfonylurea) and DPX-R9674, which is a mixture of
 thifensulfuron
 (methyl-3-[[[[(4-methoxy-6-methyl-1,3,5-triazin-2-yl)amino)
 carbonyl] amino] sulfonyl]-2-thiophenecarboxylate) and
 tribenuron (methyl
 2[[[[N-4-methoxy-6-methyl-1,3,5-triazin-2-yl) methylaminol
 carbonyl] amino] sulfonyl] benzoate). These two and
 chlorsulfuron
 (2-chloro-N-[(4-methoxy-6-methyl-1,3,5-triazin-2-yl)
 aminocarbonyl] benzenesulfonamide) were applied to two
 transgenic tobacco genotypes harboring the csr1-1 gene for
 chlorsulfuron resistance and compared with an untransformed
 control. Our purpose was to determine if transgenic seedlings
 were resistant to DPX-R9674 and amidosulfuron. The experiment
 was a factorial in a completely randomized design with 25
 replications. The three herbicides were applied to the
 transgenic and control seedlings at three rates. The
 transgenic seedlings had significantly higher leaf area, top
 dry weight, and root dry weight than the untransformed control
 when sprayed with any of the three herbicides. Seedlings were
 highly resistant to amidosulfuron and chlorsulfuron.
 Resistance to DPX-R9674 in the transgenic seedlings was
 minimal, which was unexpected, considering that an analysis of
 AHAS activity revealed high levels of cross-resistance to
 chlorsulfuron, DPX-R9674, and amidosulfuron. It is possible
 that DPX-R9674 is metabolized into products that are
 herbicidally active at different AHAS binding sites. One of
 transgenic lines was more resistant to herbicide application
 than the other indicating that selection for maximum gene
 expression among transgenic lines is necessary part of
 transgenic cultivar development.  It  was conclued that DPX-
 R9674 would not be suitable for use with transgenic crops
 harboring the csr1-1 gene for chlorsulfuron resistance.  The
 other low-residual sulfonylurea, amidosulfuron, was more
 promising.
 
 
 277                                   NAL Call. No.: 79.8 W41
 Response of a chlorsulfuron-resistant biotype of Kochia
 scoparia to sulfonylurea and alternative herbicides.
 Friesen, L.F.; Morrison, I.N.; Rashid, A.; Devine, M.D.
 Champaign, Ill. : Weed Science Society of America; 1993 Jan.
 Weed science v. 41 (1): p. 100-106; 1993 Jan.  Includes
 references.
 
 Language:  English
 
 Descriptors: Manitoba; Cabt; Kochia scoparia; Biotypes;
 Chlorsulfuron; Herbicide resistance; Herbicide resistant
 weeds; Cross resistance; Susceptibility; Herbicides; Weed
 control
 
 Abstract:  Kochia growing on an industrial site where
 chlorsulfuron was applied repeatedly over several seasons was
 confirmed to be resistant to chlorsulfuron and several other
 acetolactate synthase (ALS) -inhibiting herbicides. In growth
 room experiments, resistant (R) plants were 2 to > 180 times
 more resistant to five sulfonylurea herbicides and one
 imidazolinone herbicide (imazethapyr) than susceptible (S)
 plants, as measured by the ratio of dosages required to
 inhibit shoot dry matter accumulation by 50% (GR50 R/S).
 Similarly, in vitro assays of ALS activity indicated that from
 3 to 30 times more herbicide was required to inhibit the
 enzyme from R plants than from S plants. Results of ALS enzyme
 assays indicated that R kochia was approximately equally
 resistant to metsulfuron, triasulfuron, and thifensulfuron,
 and 2.5 times more resistant to tribenuron than
 thifensulfuron. However, the response of R kochia growing in a
 spring wheat crop in the field was not consistent with results
 of the ALS enzyme assays. In field experiments, thifensulfuron
 at 32 g ai ha-1 had little effect on R kochia. In contrast,
 metsulfuron, triasulfuron, and tribenuron at 8 g ha-1 did not
 reduce R kochia seedling densities, but caused severe stunting
 such that 2 mo after treatment the shoot biomass of plants in
 untreated plots was four times greater than in sprayed plots.
 Herbicides with alternative modes of action including
 fluroxypyr, bromoxynil/MCPA ester, dichlorprop/2,4-D ester,
 and 2,4-D ester provided good control of R kochia in the
 field. Quinclorac did not reduce kochia densities, but
 surviving plants were stunted. To delay or avoid development
 of ALS inhibitor-resistant kochia populations, these
 alternative herbicides applied alone or in tank mixtures could
 be incorporated into a herbicide rotation.
 
 
 278                                  NAL Call. No.: SB610.W39
 Response of common bean (Phaseolus vulgaris) cultivars to
 metobromuron. Park, S.J.; Hamill, A.S.
 Champaign, Ill. : The Weed Science Society of America; 1993
 Jan. Weed technology : a journal of the Weed Science Society
 of America v. 7 (1): p. 70-75; 1993 Jan.  Includes references.
 
 Language:  English
 
 Descriptors: Ontario; Cabt; Phaseolus vulgaris; Cultivars;
 Varietal susceptibility; Metobromuron; Herbicide resistance;
 Screening; Phytotoxicity; Crop damage; Seedling stage;
 Application rates
 
 
 279                                   NAL Call. No.: 79.8 W41
 Response of corn (Zea mays L.) inbreds and hybrids to
 sulfonylurea herbicides. Green, J.M.; Ulrich, J.F.
 Champaign, Ill. : Weed Science Society of America; 1993 Jul.
 Weed science v. 41 (3): p. 508-516; 1993 Jul.  Includes
 references.
 
 Language:  English
 
 Descriptors: Zea mays; Inbred lines; Hybrids; Herbicide
 resistance; Sulfonylurea herbicides; Chlorimuron; Metsulfuron;
 Tribenuron; Sulfometuron; Phytotoxicity; Varietal
 susceptibility; Recessive genes; Plant breeding
 
 Abstract:  Extensive field and greenhouse studies were done to
 characterize varietal response of three recently
 commercialized sulfonylurea corn herbicides: nicosulfuron,
 primisulfuron, and thifensulfuron. Most of the 94 varieties
 tested were highly tolerant to these herbicides. The 37
 inbreds represented all major inbred families now used in
 hybrid seed production as well as several sensitive
 experimentals. Twenty-one defined hybrids from these inbreds
 as well as 36 commercially coded hybrids were also tested.
 Sensitive inbreds produced tolerant hybrids when crossed with
 tolerant inbreds. Sensitive hybrids occurred when both parents
 were sensitive. Genetic analysis of sensitive by tolerant
 crosses showed that sensitivity is controlled by a single
 recessive gene. Nicosulfuron had the widest corn safety margin
 and fewest sensitive varieties. Dose response analysis showed
 varieties can vary more than 40 000-fold in sensitivity. Only
 corn varieties with the AHAS-modified XA-17 gene showed any
 change in enzyme sensitivity. This gene overcame sensitivity
 to sulfonylureas, even when the organophosphate insecticide
 terbufos was present. Thus, breeders have three options to
 eliminate sulfonylurea sensitivity: backcross sensitive
 inbreds with tolerant, always use at least one tolerant hybrid
 parent, or use the XA-17 gene.
 
 
 280                                  NAL Call. No.: SB610.W39
 Response of quackgrass (Elytrigia repens) biotypes to
 primisulfuron. Gillespie, G.R.; Vitolo, D.B.
 Champaign, Ill. : The Weed Science Society of America; 1993
 Apr. Weed technology : a journal of the Weed Science Society
 of America v. 7 (2): p. 411-416; 1993 Apr.  Includes
 references.
 
 Language:  English
 
 Descriptors: New York; Cabt; Ohio; Cabt; Pennsylvania; Cabt;
 Minnesota; Cabt; Massachusetts; Cabt; North Dakota; Cabt;
 Elymus repens; Biotypes; Weed biology; Herbicide resistant
 weeds; Provenance; Herbicide resistance; Sulfonylurea
 herbicides; Weed control; Chemical control; Application rates;
 Additives
 
 
 281                                   NAL Call. No.: 500 T25A
 Response of several cucumber cultivar seedlings to
 ethalfluralin and pendimethalin in vitro.
 Kennedy, J.M.; Caponetti, J.D.; Jeffery, L.S.
 Hixson, Tenn. : The Academy; 1991 Jul.
 Journal of the Tennessee Academy of Science v. 66 (3): p.
 111-114; 1991 Jul. Includes references.
 
 Language:  English
 
 Descriptors: Cucumis sativus; Cultivars; Seedlings; Injuries;
 Herbicide resistance; Ethalfluralin; Pendimethalin
 
 
 282                        NAL Call. No.: ArUSB608.R5B42 1991
 Rice response to rotational crop herbicides.
 Beaty, Jackie Dwayne
 1991; 1991.
 x, 47 leaves ; 28 cm.  May 1991.  Includes bibliographical
 references (leaf 16).
 
 Language:  English
 
 Descriptors: Rice; Herbicide resistance; Crop rotation
 
 
 283                                  NAL Call. No.: SB951.P49
 Role of glutathione and glutathione S-transferase in the
 selectivity of acetochlor in maize and wheat.
 Jablonkai, I.; Hatzios, K.K.
 Orlando, Fla. : Academic Press; 1991 Nov.
 Pesticide biochemistry and physiology v. 41 (3): p. 221-231;
 1991 Nov. Includes references.
 
 Language:  English
 
 Descriptors: Zea mays; Triticum aestivum; Roots; Shoots; Plant
 composition; Chemical composition; Glutathione; Enzyme
 activity; Glutathione transferase; Metabolic detoxification;
 Acetochlor; Selectivity; Hybrid varieties; Cultivars; Varietal
 susceptibility; Genotypes; Genetic variation; Seedlings;
 Phytotoxicity; Herbicide resistance; Pharmacokinetics
 
 Abstract:  The role of shoot and root glutathione (GSH)
 content and glutathione S-transferase (GST) activity in the
 response of the 'A632 X A635' and 'Anjou SC256' hybrids of
 maize (Zea mays L.) and of 'Jubilejnaja 50' wheat (Triticum
 aestivum L.) to the chloroacetanilide herbicide acetochlor was
 evaluated. The concentrations of root-applied acetochlor
 causing a 50% inhibition of plant shoot height were 20
 micromoles for the tolerant 'A632 X A635' maize, 1 micromole
 for the sensitive 'Anjou SC256' maize, and 0.1 micromoles for
 the very sensitive 'Jubilejnaja 50' wheat. The nonprotein
 thiol (mainly GSH) level in the roots of the tolerant 'A632 X
 A635' maize hybrid was 2-fold greater than that found in the
 roots of the sensitive maize hybrid and of wheat. Pretreatment
 with 10 micromoles of acetochlor induced the root nonprotein
 thiol levels of all three genotypes. The highest induction of
 root thiol content compared to controls was observed at 48 hr
 after acetochlor treatment and was 2.23-fold in the tolerant
 maize and 1.72-fold for the sensitive wheat. GST activities of
 etiolated maize and wheat seedlings were evaluated using both
 CDNB (1-chloro-2,4-dinitrobenzene) and [14C]-acetochlor as
 substrates. GST(CDNB) activity was greater in the roots than
 in the shoots of both maize hybrids. The shoot activity of
 both maize genotypes was similar, but the tolerant 'A632 X
 A635' maize had slightly higher root GST(CDNB) activity. In
 the sensitive wheat, similar shoot and root activities were
 observed. GST(CDNB) activity in roots of the maize hybrids and
 of wheat was enhanced by 70-100% at 48 hr after pretreatment
 with 10 micromoles of acetochlor. Shoot GST(CDNB) activity of
 maize or wheat was not induced significantly by acetochlor
 pretreatment. Root and shoot GST(acetochlor) activities of the
 maize hybrids and wheat were much lower than GST(CDNB)
 activities. Root GST(acetochlor) activities of the two maize
 hybrids were greater and more inducible by acetochlor
 pretreatment than those of the sensitive wheat.  These results
 demonstrate the important role of endogenous levels of GSH and
 of GST activity in chloroacetanilide herbicide detoxication
 and selectivity.
 
 
 284                                   NAL Call. No.: 450 P692
 S1 destabilization and higher sensitivity to light in
 metribuzin-resistant mutants.
 Perewoska, I.; Etienne, A.L.; Miranda, T.; Kirilovsky, D.
 Rockville, MD : American Society of Plant Physiologists, 1926-
 ; 1994 Jan. Plant physiology v. 104 (1): p. 235-245; 1994 Jan. 
 Includes references.
 
 Language:  English
 
 Descriptors: Cyanobacteria; Photosystem ii; Redox potential;
 Electron transfer; Quinones; Binding proteins; Herbicide
 resistance; Metribuzin; Mutants; Mutations; Photoinhibition;
 Light; Stress; Amino acid sequences; Structural genes
 
 Abstract:  Mutations in the secondary quinone electron
 acceptor pocket of the D1 protein conferring a modification on
 the donor side of photosystem II (PSII) have been
 characterized by gene cloning and sequencing in two
 metribuzin-resistant mutants of Synechocystis PCC 6714. The
 mutations induce different herbicide resistances: in M30, a
 point mutation at the codon 248, isoleucine to threonine,
 results in resistance only to metribuzin; in a single
 mutation, Ala251Val, confers metribuzin, atrazine, and ioxynil
 resistance. As with other herbicide-resistant mutants, and
 present modifications in the electron transfer between the
 primary quinone electron acceptor and (QA) and QB. In
 addition, they have a modified oscillatory pattern of oxygen
 emission: after dark adaptation, the maximum oscillation is
 shifted by one flash. Both mutants have a higher concentration
 of the redox state in the dark-adapted state than the wild
 type. The mutations render the oxygen-evolving system more
 accessible to cell reductants. The mutation Ala251Val also
 confers to PSII an increased sensitivity to high light. We
 have already demonstrated that underlight stress a double
 mutant, AzV (Ala251Val, Phe211Ser), lost the ability to
 recover the PSII activity sooner than the wild type. Here, we
 confirm that the modification of the alanine-251 is
 responsible for this specific sensitivity to high light. We
 conclude that specific mutations of the QB pocket modify the
 behavior of the cells under light stress and have an effect on
 the structure of the D1 protein in the other side of the
 membrane.
 
 
 285                                  NAL Call. No.: SB610.W39
 Seed biology of sulfonylurea-resistant and -susceptible
 biotypes of prickly lettuce (Lactuca serriola).
 Alcocer-Ruthling, M.; Thill, D.C.; Shafii, B.
 Champaign, Ill. : The Weed Science Society of America; 1992
 Oct. Weed technology : a journal of the Weed Science Society
 of America v. 6 (4): p. 858-864; 1992 Oct.  Includes
 references.
 
 Language:  English
 
 Descriptors: Idaho; Cabt; Lactuca serriola; Biotypes;
 Sulfonylurea herbicides; Herbicide resistance; Susceptibility;
 Competitive ability; Seed longevity; Seed germination;
 Fecundity
 
 
 286                                  NAL Call. No.: QK725.P54
 Selection of atrazine tolerant soybean calli and expression of
 that tolerance in regenerated plants.
 Wrather, J.A.; Freytag, A.H.
 Berlin, W. Ger. : Springer International; 1991.
 Plant cell reports v. 10 (1): p. 44-47; 1991.  Includes
 references.
 
 Language:  English
 
 Descriptors: Glycine max; Plant breeding; In vitro selection;
 Atrazine; Herbicide resistance; Callus; Regenerative ability;
 Phytotoxicity; Selection
 
 Abstract:  Lines of soybean [Glycine max (L.)] tolerant of
 atrazine were developed by an in vitro and in vivo atrazine
 challenge. Cotyledonary node plus epicotyl explants from
 mature germinated seed of soybean introduction PI 438489B were
 cultured on RV-5 medium containing 48 mg active ingredient
 (a.i.)/l atrazine for one month. Most of the explants (66%) on
 medium containing atrazine, and 10% on medium without atrazine
 died. Explants surviving exposure to atrazine callused and
 organogenically regenerated shoots developed. Soil around R0
 plants regenerated from atrazine tolerant shoots and
 nonatrazine challenged shoots (controls) were subsequently
 tested in vivo for atrazine tolerance. All controls died.
 Seeds were collected from atrazine tolerant R0 plants. Two
 weeks after planting, emerged R1 seedlings were tested in vivo
 for atrazine tolerance as the R0 plants were. This procedure
 was repeated on the R2 plants. All nonatrazine selected
 control plants died when exposed to this herbicide. Atrazine
 tolerant R2 plants were maintained in atrazine amended soil
 and appeared as healthy and vigorous as the control growing in
 atrazine free soil.
 
 
 287                                  NAL Call. No.: QK710.P63
 Selective agents and marker genes for use in transformation of
 monocotyledonous plants.
 Wilmink, A.; Dons, J.J.M.
 Athens, Ga. : International Society for Plant Molecular
 Biology, University of Georgia; 1993 Jun.
 Plant molecular biology reporter - ISPMB v. 11 (2): p.
 165-185; 1993 Jun. Literature review.  Includes references.
 
 Language:  English
 
 Descriptors: Monocotyledons; Genetic transformation;
 Selection; Marker genes; Antibiotics; Resistance; Herbicide
 resistance; Gene expression; Vectors; Literature reviews
 
 
 288                                   NAL Call. No.: 79.8 W41
 Semidominant nature of monogenic sulfonylurea herbicide
 resistance in sugarbeet (Beta vulgaris).
 Hart, S.E.; Saunders, J.W.; Penner, D.
 Champaign, Ill. : Weed Science Society of America; 1993 Jul.
 Weed science v. 41 (3): p. 317-324; 1993 Jul.  Includes
 references.
 
 Language:  English
 
 Descriptors: Beta vulgaris; Herbicide resistance; Inheritance;
 Sulfonylurea herbicides; Chlorimuron; Semidominance;
 Semidominant genes; Lines; Homozygosity; Heterozygosity;
 Enzyme activity; Enzyme inhibitors
 
 Abstract:  Greenhouse and laboratory studies were conducted to
 determine the degree of dominance of the monogenic
 sulfonylurea herbicide resistance trait in diploid sugarbeet
 by comparing the response of homozygous and heterozygous
 resistant sugarbeet to primisulfuron, thifensulfuron, and
 chlorimuron on the whole plant and acetolactate synthase (ALS)
 enzyme level. Progeny tests suggested that the monogenic
 sulfonylurea herbicide resistance was semidominant.
 Subsequently, heterozygous resistant (R-1) and homozygous
 resistant (R-2) sugarbeet lines were sprayed with increasing
 rates of primisulfuron, thifensulfuron, and chlorimuron, and
 herbicide rates required for 50% growth reduction (GR50) were
 determined. GR50 values were also determined for homozygous
 susceptible sugarbeet lines (S-1 and S-2). The GR50 values
 indicated that the R-2 sugarbeet was 377, 269, and 144 times
 more resistant to primisulfuron, thifensulfuron, and
 chlorimuron, respectively, than susceptible S-2 sugarbeet. In
 contrast, R-1 sugarbeet was only 107, 76, and 57 times more
 resistant to primisulfuron, thifensulfuron, and chlorimuron,
 respectively, than S-1 sugarbeet, indicating at least a
 twofold difference in the magnitude of resistance between
 homozygous resistant and heterozygous resistant sugarbeet
 lines. ALS enzyme activity analysis were consistentwith whole
 plant results. Thus, based on these two, maximum crop
 resistance can be obtained by developing homozygous resistant
 cultivars.
 
 
 289                                    NAL Call. No.: 450 M99
 Sensitivity of field strains of Gibberella fujikuroi (Fusarium
 section Liseola) to benomyl and hygromycin B.
 Yan, K.; Dickman, M.B.; Xu, J.R.; Leslie, J.F.
 Bronx, N.Y. : The New York Botanical Garden; 1993 Mar.
 Mycologia v. 85 (2): p. 206-213; 1993 Mar.  Includes
 references.
 
 Language:  English
 
 Descriptors: Gibberella fujikuroi; Plant pathogenic fungi;
 Benomyl; Hygromycin b; Resistance; Herbicide resistance;
 Strain differences; Genetic regulation
 
 
 290                                   NAL Call. No.: 450 P692
 A serine-to-threonine substitution in the triazine herbicide-
 binding protein in potato cells results in atrazine resistance
 without impairing productivity. Smeda, R.J.; Hasegawa, P.M.;
 Goldsbrough, P.B.; Singh, N.K.; Weller, S.C. Rockville, MD :
 American Society of Plant Physiologists, 1926-; 1993 Nov.
 Plant physiology v. 103 (3): p. 911-917; 1993 Nov.  Includes
 references.
 
 Language:  English
 
 Descriptors: Solanum tuberosum; Cells; Selection criteria;
 Herbicide resistance; Atrazine; Genes; Mutations; Thylakoids;
 Membranes; Proteins; Quinones; Photosystem ii; Photosynthesis;
 Electron transfer
 
 Abstract:  A mutation of the psbA gene was identified in
 photoautotrophic potato (Solanum tuberosum L. cv Superior X
 U.S. Department of Agriculture line 66-142) cells selected for
 resistance to
 6-chloro-N-ethyl-N'-(1-methylethyl)-1,3, 5-triazine-2,4-
 diamine (atrazine). Photoaffinity labeling with 6-azido-N-
 ethyl-N'-(1-methylethyl)-1,3, 5-triazine-2,4-diamine detected
 a thylakoid membrane protein with a Mr of 32,000 in
 susceptible, but not in resistant, cells. This protein was
 identified as the secondary quinone acceptor of photosystem II
 (QB) protein. Atrazine resistance in selected cells was
 attributable to a mutation from AGT (serine) to ACT
 (threonine) in codon 264 of the psbA gene that encodes the QB
 protein. Although the mutant cells exhibited extreme levels of
 resistance to atrazine, no concomitant reductions in
 photosynthetic electron transport or cell growth rates
 compared to the unselected cells were detected. This is in
 contrast with the losses in productivity observed in atrazine-
 resistant mutants that contain a glycine-264 alteration.
 
 
 291                                  NAL Call. No.: SB951.P49
 A similar metabolism of chlorotoluron in cell suspension
 cultures from near-isogenic susceptible and tolerant lines of
 wheat.
 Cabanne, F.; Snape, J.W.
 Orlando, Fla. : Academic Press; 1993 Sep.
 Pesticide biochemistry and physiology v. 47 (1): p. 51-59;
 1993 Sep.  Includes references.
 
 Language:  English
 
 Descriptors: Triticum aestivum; Lines; Varietal
 susceptibility; Herbicide resistance; Metabolism;
 Chlorotoluron; Metabolites; Mode of action; Cell culture; In
 vitro
 
 Abstract:  The metabolism of the herbicide chlorotoluron was
 followed in cell suspension cultures of wheat. The cultures
 originated from plants of the susceptible variety Corin, the
 tolerant variety Clement, and six near-isogenic lines, 9S,
 10S, 16S, 17T, 18T, and 24T [susceptible (S) and tolerant (T),
 respectively]. The six lines had the genetic background of the
 susceptible variety Chinese Spring, but the three lines 17T,
 18T, and 24T contained a gene for tolerance (Sul) transferred
 from the variety Cappelle-Desprez. The cultures from Corin and
 Clement produced identical patterns of metabolites which were
 also identical to those found in plants. The rate of
 metabolism of the herbicide was slightly higher in the cell
 culture of Clement (T) than in Corin (S), as reported for the
 corresponding plants. Patterns of metabolites were similar in
 the cell cultures from the six isogenic lines. The rate of
 metabolism was the same in 9S, 10S, 16S, 18T, and 24T, and
 lower in 17T, so that a differential rate of metabolism was
 not found between T and S cell cultures. The occurrence of a
 differential rate of metabolism as the primary mechanism of
 varietal selectivity of wheat to chlorotoluron is discussed.
 
 
 292                                  NAL Call. No.: QH301.N32
 Site directed mutagenesis of a chloroplast encoded protein.
 Przibilla, E.; Yamamoto, R.
 New York, N.Y. : Plenum Press; 1992.
 NATO ASI series : Series A : Life sciences v. 226: p. 561-565.
 ill; 1992.  In the series analytic: Regulation of chloroplast
 biogenesis / edited by J.H. Argyroudi-Akoyunoglou. Proceedings
 of a NATO Advanced Research Workshop, July 28-August 3, 1991,
 Crete, Greece.  Includes references.
 
 Language:  English
 
 Descriptors: Chlamydomonas reinhardtii; Genetic engineering;
 Mutants; Thylakoids; Herbicide resistance; Phenolic compounds
 
 
 293                             NAL Call. No.: S494.5.B563B56
 Somaclonal selection for tolerance to streptomycin and
 herbicides through rice cell culture.
 Kinoshita, T.; Mori, K.; Mikami, T.
 Berlin, W. Ger. : Springer-Verlag; 1991.
 Biotechnology in agriculture and forestry (14): p. 383-404;
 1991.  In the series analtyic: Rice / edited by Y.P.S. Bajaj. 
 Includes references.
 
 Language:  English
 
 Descriptors: Oryza sativa; Cell culture; Somaclonal variation;
 In vitro selection; Herbicide resistance; Streptomycin;
 Resistance; Salt tolerance
 
 
 294                                  NAL Call. No.: SB610.W39
 Soybean (Glycine max) cultivar tolerance to chlorimuron and
 imazaquin with varying hydroponic solution pH.
 Newsom, L.J.; Shaw, D.R.
 Champaign, Ill. : The Society; 1992 Apr.
 Weed technology : a journal of the Weed Science Society of
 America v. 6 (2): p. 382-388; 1992 Apr.  Includes references.
 
 Language:  English
 
 Descriptors: Glycine max; Cultivars; Varietal susceptibility;
 Herbicide resistance; Chlorimuron; Imazaquin; Crop damage;
 Phytotoxicity; Ph; Nutrient solutions; Hydroponics
 
 
 295                                  NAL Call. No.: SB610.W39
 Soybean (Glycine max) response to chlorimuron and imazaquin as
 influenced by soil moisture.
 Newsom, L.J.; Shaw, D.R.
 Champaign, Ill. : The Society; 1992 Apr.
 Weed technology : a journal of the Weed Science Society of
 America v. 6 (2): p. 389-395; 1992 Apr.  Includes references.
 
 Language:  English
 
 Descriptors: Mississippi; Glycine max; Cultivars; Varietal
 susceptibility; Herbicide resistance; Chlorimuron; Imazaquin;
 Phytotoxicity; Environmental factors; Soil water content; Crop
 yield; Yield losses; Crop damage
 
 
 296                                    NAL Call. No.: S79 .E3
 Soybean response to quinclorac and triclopyr.
 Barrentine, W.L.; Street, J.E.
 State College, Miss. : Mississippi State University,
 Agricultural and Forestry Experiment Station, 1970-; 1993 Mar.
 Bulletin (995): 12 p.; 1993 Mar.  Includes references.
 
 Language:  English
 
 Descriptors: Mississippi; Cabt; Glycine max; Quinclorac;
 Triclopyr; Herbicide resistance; Oryza sativa; Drift; Crop
 yield; Field tests; Application rates; Injuries
 
 
 297                                  NAL Call. No.: QK725.P54
 Stably transformed herbicide resistant callus of sugarcane via
 microprojectile bombardment of cell suspension cultures and
 electroporation of protoplasts. Chowdhury, M.K.U.; Vasil, I.K.
 Berlin, W. Ger. : Springer International; 1992.
 Plant cell reports v. 11 (10): p. 494-498; 1992.  Includes
 references.
 
 Language:  English
 
 Descriptors: Saccharum; Genetic transformation; Gene transfer;
 Cell suspensions; Callus; Protoplasts; Electroporation;
 Plasmids; Herbicide resistance
 
 Abstract:  Stably transformed callus of a hybrid sugarcane
 cultivar (Saccharum species hybrid, CP72-1210) was achieved
 following high velocity microprojectile bombardment of
 suspension culture cells, and electroporation of protoplasts.
 A three-day old cell suspension culture (SC88) was bombarded
 with gold particles coated with pBARGUS plasmid DNA containing
 the B-glucuronidase (GUS) reporter gene and the bar selectable
 gene that confers resistance to the herbicide basta. The
 pBARGUS plasmid was also electroporated into the protoplasts
 of another cell line (SCPP). Colonies resistant to basta were
 recovered from both sources. Stable integration of the bar
 gene in the resistant cell lines was confirmed by Southern
 analysis. In addition, phosphinothricin acetyltransferase
 (PAT) activity was also demonstrated in the transformed cell
 lines.
 
 
 298                                   NAL Call. No.: 100 F663
 Strategies in breeding herbicide resistant lettuce.
 Nagata, R.T.; Dusky, J.A.; Torres, A.C.; Cantliffe, D.J.;
 Feri, R.J.; Bewick, T.A.
 Belle Glade, Fla. : The Center; 1993 Feb.
 Belle Glade EREC research report EV - Florida University
 Agricultural Research and Education Center (1993-2): p.
 97-104; 1993 Feb.  Paper presented at the Lettuce Research
 Workshop, February 4, 1993, Belle Glade, Florida.  Includes
 references.
 
 Language:  English
 
 Descriptors: Florida; Lactuca sativa; Herbicide resistance;
 Plant breeding; Weed control; Glyphosate; Sulfonylurea
 herbicides; Gene splicing; Backcrossing
 
 
 299                                   NAL Call. No.: 500 N21P
 Structure and topological symmetry of the glyphosate target 5-
 enol-pyruvylshikimate-3-phosphate synthase: A distinctive
 protein fold. Stallings, W.C.; Abdel-Meguid, S.S.; Lim, L.W.;
 Shieh, H.S.; Dayringer, H.E.; Leimgruber, N.K.; Stegeman,
 R.A.; Anderson, K.S.; Sikorski, J.A.; Padgette, S.R.; Kishore,
 G.M.
 Washington, D.C. : The Academy; 1991 Jun01.
 Proceedings of the National Academy of Sciences of the United
 States of America v. 88 (11): p. 5046-5050; 1991 Jun01. 
 Includes references.
 
 Language:  English
 
 Descriptors: Glyphosate; Herbicide resistance; Plant
 physiology; Lyases; Amino acids; Aromatic acids; Biosynthesis;
 Escherichia coli; X radiation
 
 Abstract:  5-enol-Pyruvylshikimate -3-phosphate synthase (EPSP
 synthase; phosphoenolpyruvate:3-phosphoshikimate 1-
 carboxyvinyltransferase, EC 2.5.1.19) is an enzyme on the
 pathway toward the synthesis of aromatic amino acids in
 plants, fungi, and bacteria and is the target of the broad-
 spectrum herbicide glyphosate. The three-dimensional structure
 of the enzyme from Escherichia coli has been determined by
 crystallographic techniques. The polypeptide backbone chain
 was traced by examination of an electron density map
 calculated at 3-A resolution. The two-domain structure has a
 distinctive fold and appears to be formed by 6-fold
 replication of a protein folding unit comprising two parallel
 helices and a four-stranded sheet. Each domain is formed from
 three of these units, which are related by an approximate
 threefold symmetry axis; in each domain three of the helices
 are completely buried by a surface formed from the three beta-
 sheets and solvent-accessible faces of the other three
 helices. The domains are related by an approximate dyad, but
 in the present crystals the molecule does not display pseudo-
 symmetry related to the symmetry of point group 32 because its
 approximate threefold axes are almost normal. A possible
 relation between the three-dimensional structure of the
 protein and the linear sequence of its gene will be described.
 The topological threefold symmetry and orientation of each of
 the two observed globular domains may direct the binding of
 substrates and inhibitors by a helix macrodipole effect and
 implies that the active site is located near the interdomain
 crossover segments. The structure also suggests a rationale
 for the glyphosate tolerance conferred by sequence
 alterations.
 
 
 300                                   NAL Call. No.: 381 J824
 Structure of an mdr-like gene from Arabidopsis thaliana:
 evolutionary implications.
 Dudler, R.; Hertig, C.
 Baltimore, Md. : American Society for Biochemistry and
 Molecular Biology; 1992 Mar25.
 The Journal of biological chemistry v. 267 (9): p. 5882-5888;
 1992 Mar25. Includes references.
 
 Language:  English
 
 Descriptors: Arabidopsis thaliana; Glycoproteins; Structural
 genes; Cloning; Nucleotide sequences; Amino acid sequences;
 Introns; Exons; Evolution; Herbicide resistance
 
 Abstract:  Multidrug resistance of mammalian tumor cells is
 caused by the enhanced expression of P-glycoproteins. These
 proteins are encoded by mdr genes and mediate the energy-
 dependent efflux of a variety of lipophilic drugs from cells.
 To test whether in plants mdr-like genes might be involved in
 certain cases of cross-resistance to different herbicides, we
 have cloned and characterized a gene from Arabidopsis
 thaliana, atpgp1, encoding a putative P-glycoprotein
 homologue. Like the mammalian P-glycoproteins, with which it
 shares extensive sequence homology and a similar organization
 in structural domains, this protein is internally duplicated.
 Seven of the nine introns in the atpgp1 gene match introns in
 the mammalian mdr genes to within a few nucleotides, and the
 positions of these suggest that P-glycoprotein genes evolved
 by duplication and subsequent fusion of an intron-containing
 primordial gene prior to the evolutionary separation of plants
 and mammals. The atpgp1 gene gives rise to transcripts present
 in all plant parts but particularly abundant in inflorescence
 axes.
 
 
 301                                  NAL Call. No.: QK710.P62
 Structure of the amplified 5-enolpyruvylshikimate-3-phosphate
 synthase gene in glyphosate-resistant carrot cells.
 Suh, H.; Hepburn, A.G.; Kriz, A.L.; Widholm, J.M.
 Dordrecht : Kluwer Academic Publishers; 1993 May.
 Plant molecular biology v. 22 (2): p. 195-205; 1993 May. 
 Includes references.
 
 Language:  English
 
 Descriptors: Daucus carota; Structural genes; Amplification;
 Alkyl (aryl) transferases; Glyphosate; Herbicide resistance;
 Cell lines; Nucleotide sequences; Restriction mapping;
 Repetitive  DNA
 
 Abstract:  The structure of amplified 5-
 enolpyruvylshikimate-3-phosphate synthase (EPSPS) DNA of
 carrot suspension-cultured cell lines selected for glyphosate
 resistance was analysed to determine the mechanism of gene
 amplification in this plant system. Southern hybridization of
 the amplified DNA digested with several restriction enzymes
 probed with a petunia EPSPS cDNA clone showed that there were
 differences in fragment sizes in the amplified DNA from one
 highly resistant cell line in comparison with the parental
 line. Cloning of the EPSPS gene and 5' flanking sequences was
 carried out and two different DNA structures were revealed. A
 13 kb clone contained only one copy of the EPSPS gene while a
 16 kb clone contained an inverted duplication of the gene.
 Southern blot analysis with a carrot DNA probe showed that
 only the uninverted repeated DNA structure was present in all
 of the cell lines during the selection process and the
 inverted repeat (IR) was present only in highly amplified DNA.
 The two structures were present in about equal amounts in the
 highly amplified line, TC 35G, where the EPSPS gene was
 amplified about 25-fold. The presence of the inverted repeat
 (IR) was further verified by re-sistance to S1 nuclease
 hydrolysis after denaturation and rapid renaturation, showing
 foldback DNA with the IR length being 9.5 kb. The junction was
 also sequenced. Mapping of the clones showed that the size of
 the amplified carrot EPSPS gene itself is about 3.5 kb. This
 is the first report of an IR in amplified DNA of a target
 enzyme gene in selected plant cells.
 
 
 302                                  NAL Call. No.: SB951.P47
 Structure-activity relationships of triazinone herbicides on
 resistant weeds and resistant Chlamydomonas reinhardtii.
 Oettmeier, W.; Hilp, U.; Draber, W.; Fedtke, C.; Schmidt, R.R.
 Essex : Elsevier Applied Science Publishers; 1991.
 Pesticide science v. 33 (4): p. 399-409; 1991.  Includes
 references.
 
 Language:  English
 
 Descriptors: Amaranthus retroflexus; Chenopodium album;
 Chlamydomonas reinhardtii; Mutants; Herbicide resistance;
 Herbicide resistant weeds; Atrazine; Metribuzin; Structure
 activity relationships; Photosystem ii; Inhibition; Wild
 strains
 
 Abstract:  Weeds resistant to the s-triazine herbicide
 atrazine also show resistance to the triazinone herbicide
 metribuzin. However, with highly lipophilic triazinones,
 thylakoids isolated from atrazine-resistant Amaranthus
 retroflexus (mutation at position Ser264 of the photosystem II
 D-1 reaction centre protein) in general show a higher pI(50)
 value in photosystem II electron transport than those from the
 wild type (i.e. negative cross-resistance;
 'supersensitivity'). A quantitative structure-activity
 relationship (QSAR) can be established, wherein the
 lipophilicity of the compound plays a major role. In in-vivo
 experiments, it was found that the triazinone DRW2698 killed
 resistant Amaranthus retroflexus and Chenopodium album whereas
 the wild type was almost unaffected. Triazinones were further
 investigated in five different mutants of Chlamydomonas
 reinhardtii (mutations in the D-1 protein at positions Ser264,
 Ala251, Leu275, Phe255 and Val219). Inhibitory activity of all
 triazinones was generally enhanced in the Phe255 mutant but
 decreased in the Val219 mutant. In the other mutants,
 biological activity was decreased when position 3 of the
 triazinone was substituted by CH3, OCH3, SCH3, NHCH3 or
 N(CH3)2. However, negative cross-resistance was again observed
 when this position was occupied by free thiol. It is therefore
 suggested that these two groups of triazinones orient
 themselves differently within the herbicide binding niche of
 the photosystem II D-1 protein.
 
 
 303                                   NAL Call. No.: 450 P692
 A sulfonylurea herbicide resistance gene from Arab idopsis
 thaliana as a new selectable marker for producti on of fertile
 transgenic rice plants. Li, Z.; Hayashimoto, A.; Murai, N.
 Rockville, MD : American Society of Plant Physiologists, 1926-
 ; 1992 Oct. Plant physiology v. 100 (2): p. 662-668; 1992 Oct. 
 Includes references.
 
 Language:  English
 
 Descriptors: Arabidopsis thaliana; Oryza sativa; Marker genes;
 Oxo-acid-lyases; Mutations; Mutants; Genetic transformation;
 Transgenic plants; In vitro selection; Herbicide resistance;
 Chlorsulfuron; Direct DNAuptake; Protoplasts
 
 Abstract:  A mutant acetolactate synthase (ALS) gene, csr1-1,
 isolated from sulfonylurea herbicide-resistant Arabidopsis
 thaliana, was placed under control of a cauliflower mosaic
 virus 35S promoter (35S). Rice protoplasts were transformed
 with the 35S/ALS chimeric gene and regenerated into fertile
 transgenic rice (Oryza sativa) plants. The 35S/ALS gene was
 expressed effectively as demonstrated by northern blot
 hybridization analysis, and conferred to transformed calli at
 least 200-fold greater chlorsulfuron resistance than
 nontransformed control calli. Effective selection of 35S/ALS-
 transformed protoplasts was achieved at extremely low
 chlorsulfuron concentrations of 10 nm. The results
 demonstrated that the 35S/ALS gene is an alternative
 selectable marker for rice protoplast transformation and
 fertile transgenic rice production. The results also suggest
 that the mutant form of Arabidopsis ALS enzyme operates
 normally in rice cells. Thus, the mechanism of protein
 transport to chloroplast and ALS inhibition by chlorsulfuron
 is apparently conserved among plant species as diverse as
 Arabidopsis (dicotyledon) and rice (monocotyledon).
 
 
 304                                  NAL Call. No.: SB951.P49
 Sulfonylurea herbicide resistance in common chickweed,
 perennial ryegrass, and Russian thistle.
 Saari, L.L.; Cotterman, J.C.; Smith, W.F.; Primiani, M.M.
 Orlando, Fla. : Academic Press; 1992 Feb.
 Pesticide biochemistry and physiology v. 42 (2): p. 110-118;
 1992 Feb. Includes references.
 
 Language:  English
 
 Descriptors: Stellaria media; Lolium perenne; Salsola iberica;
 Herbicide resistance; Chlorsulfuron; Sulfometuron;
 Triasulfuron; Imazapyr; Biotypes; Herbicide resistant weeds;
 Dry matter accumulation; Resistance mechanisms; Enzyme
 activity; Ligases; Metabolic detoxification; Pharmacokinetics
 
 Abstract:  Sulfonylurea herbicide resistance was demonstrated
 in two broadleaf species, common chickweed (Stellaria media
 [L]. Vill.) and Russian thistle (Salsola iberica Sennen &
 Pau), and in one grass species, perennial ryegrass (Lolium
 perenne L.), in greenhouse tests by determining the
 sulfonylurea and imidazolinone herbicide rates required to
 reduce the dry weight accumulation of resistant and
 susceptible weed biotypes. The herbicide resistance in each of
 the three weed biotypes was due to an acetolactate synthase
 (ALS) enzyme that was less sensitive to inhibition by ALS-
 inhibiting herbicides, including five sulfonylurea, one
 imidazolinone, and one dichlorosulfonanilide herbicides. The
 Km (pyruvate) and specific activity values associated with ALS
 isolated from the resistant biotypes were similar in magnitude
 to those obtained with ALS isolated from susceptible biotypes.
 Both susceptible and resistant biotypes of each weed species
 metabolized radiolabeled sulfonylurea herbicides at similar
 rates, indicating that herbicide metabolism was not
 contributing to the differential plant response of the
 biotypes to ALS-inhibiting herbicides.
 
 
 305                                     NAL Call. No.: SB1.H6
 Sweet corn to cultivars respond differentially to the
 herbicide nicosulfuron. Stall, W.M.; Bewick, T.A.
 Alexandria, Va. : American Society for Horticultural Science;
 1992 Feb. HortScience v. 27 (2): p. 131-133; 1992 Feb. 
 Includes references.
 
 Language:  English
 
 Descriptors: Zea mays; Cultivars; Sweetcorn; Sulfonylurea
 herbicides; Application rates; Herbicide resistance; Varietal
 susceptibility; Genes; Phytotoxicity; Herbicide mixtures;
 Terbufos; Chlorpyrifos
 
 Abstract:  Twelve sweet corn (Zea mays L. var. rugosa Bonaf.)
 cultivars were tested for response to nicosulfuron at rates of
 0, 18, 36, and 72 g a.i./ha. Weight of marketable ears
 indicated that five cultivars were intolerant to the
 herbicide. Three of the cultivars that were intolerant
 contained the shrunken-2 endosperm mutant (sh2) and two
 contained the sugary enhancer endosperm mutant (se). Cultivars
 that were most tolerant of nicosulfuron contained the sh2
 gene. Incorporation of terbufos insecticide before planting
 led to decreased marketable yield when nicosulfuron was
 applied at 36 g.ha-1 in all cultivars tested. Chlorpyrifos
 insecticide incorporated before planting did not affect
 tolerance to nicosulfuron. Neither soil-applied insecticide
 affected yield when nicosulfuron was not applied.
 
 
 306                                  NAL Call. No.: SB610.W39
 Sweet corn (Zea mays) hybrid tolerance to nicosulfuron.
 Morton, C.A.; Harvey, R.G.
 Champaign, Ill. : The Society; 1992 Jan.
 Weed technology : a journal of the Weed Science Society of
 America v. 6 (1): p. 91-96; 1992 Jan.  Includes references.
 
 Language:  English
 
 Descriptors: Wisconsin; Zea mays; Hybrids; Screening;
 Herbicide resistance; Sulfonylurea herbicides; Phytotoxicity;
 Growth rate; Crop damage; Varietal susceptibility
 
 
 307                                     NAL Call. No.: HD1.A3
 Systems approaches to quantify crop-weed interactions and
 their application in weed management.
 Kropff, M.J.; Lotz, L.A.P.
 Essex : Elsevier Applied Science Publishers; 1992.
 Agricultural systems v. 40 (1/3): p. 265-282; 1992.  In the
 special issue: Systems approaches for agricultural development
 / edited by P.S. Teng and F. Penning de Vries. Proceedings of
 an international symposium held December 2-9, 1991, Bangkok,
 Thailand.  Includes references.
 
 Language:  English
 
 Descriptors: Plant interaction; Pest management; Crop
 management; Integrated control; Yield losses; Plant density;
 Systems approach; Simulation models; Growth models; Herbicide
 resistance; Weed control; Weed competition; Leaf area
 
 
 308                                  NAL Call. No.: SB610.W39
 Technology transfer for herbicide-tolerant weeds and
 herbicide-tolerant crops. Knake, E.L.
 Champaign, Ill. : The Society; 1992 Jul.
 Weed technology : a journal of the Weed Science Society of
 America v. 6 (3): p. 662-664; 1992 Jul.  Paper presented at
 the Symposium, "Development of Herbicide-Resistant Crop
 Cultivars", Weed Science Society of America, February 6, 1991,
 Louisville, Kentucky.  Includes references.
 
 Language:  English
 
 Descriptors: Transgenic plants; Crops; Herbicide resistance;
 Weeds; Biotechnology; Weed control; Technology transfer
 
 
 309                                   NAL Call. No.: 79.8 W41
 Terbacil and bromacil cross-resistance in powell amaranth
 (Amaranthus powellii).
 Boydston, R.A.; Al-Khatib, K.
 Champaign, Ill. : Weed Science Society of America; 1992.
 Weed science v. 40 (4): p. 513-516; 1992.  Includes
 references.
 
 Language:  English
 
 Descriptors: Idaho; Amaranthus powellii; Biotypes; Herbicide
 resistance; Triazine herbicides; Cross resistance; Bromacil;
 Terbacil; Binding site; Thylakoids
 
 Abstract:  A triazine-resistant Powell amaranth biotype
 collected in Idaho was approximately six times more resistant
 to terbacil and sixteen times more resistant to bromacil than
 a normal susceptible biotype when planted into terbacil- or
 bromacil-treated soil. The concentration of terbacil required
 to reduce photosystem II activity by 50% (I50) in isolated
 thylakoids was 0.24 and 13.33 micromolar for the susceptible
 and resistant biotypes, respectively. Likewise, the I50 values
 for bromacil were 0.33 and 18.4 micromolar for the susceptible
 and resistant biotypes, respectively. More 14C-terbacil was
 bound to isolated thylakoids of the susceptible than the
 resistant biotype with binding constants (Kb) of 0.26 and 12.9
 micromolar, respectively, indicating that resistance was at
 the chloroplast level.
 
 
 310                                   NAL Call. No.: S587.T47
 Tolerance of almond to herbicides.
 Saavedra, M.; Natera, C.
 London : Association of Applied Biologists : c1980-; 1993 Apr.
 Tests of agrochemicals and cultivars (14): p. 82-83; 1993 Apr. 
 Supplement to Annals of applied biology, volume 122.  Includes
 references.
 
 Language:  English
 
 Descriptors: Prunus dulcis; Herbicides; Tolerance;
 Phytotoxicity; Mediterranean climate
 
 
 311                                     NAL Call. No.: SB1.H6
 Tolerance of apple and peach trees to triclopyr.
 Derr, J.F.
 Alexandria, Va. : The American Society for Horticultural
 Science; 1993 Oct. HortScience : a publication of the American
 Society for Horticultural Science v. 28 (10): p. 1021-1023;
 1993 Oct.  Includes references.
 
 Language:  English
 
 Descriptors: Virginia; Cabt; Malus pumila; Prunus persica;
 Orchards; Fruit trees; Weed control; Chemical control;
 Triclopyr; Phytotoxicity; Crop damage; Herbicide resistance;
 Application rates; Glyphosate; 2,4-d
 
 Abstract:  The tolerance of newly planted apple (Malus
 domestica Borkh.) and peach [Prunuspersica (L.) Batsch] trees
 to the postemergence herbicide triclopyr was evaluated in
 field trials. Apple and peach trees were not injured by
 triclopyr applied at rates ranging from 0.28 to 1.12 kg acid
 equivalent (a.e.)/ha as a directed spray to soil. No injury
 was observed following direct application of 10 ml of a
 triclopyr solution at 2 g a.e/liter to the lower bark of
 either tree species. Applications of that solution to an
 individual branch injured or killed the treated apple or peach
 branch but did not affect the rest of the tree. No reduction
 in tree growth or injury was noted 1 year after triclopyr
 application. Applications of 10 ml of a glyphosate solution at
 15 g a.i./liter to an apple branch caused severe injury and a
 growth reduction by 1 year after application, and killed all
 treated peach trees when applied to one branch. No triclopyr
 or 2,4-D treatment had affected apple or peach trunk diameter,
 number of branches, or tree size 1 year after application.
 
 
 312                                  NAL Call. No.: 79.9 W52R
 Tolerance of Kentucky bluegrass seedlings to three wild oat
 herbicides in greenhouse experiments.
 Swensen, J.B.; Dial, M.J.; Murray, G.A.; Thill, D.C.
 S.l. : The Society; 1993.
 Research progress report - Western Society of Weed Science. p.
 III/46-III/48; 1993.  Meeting held March 9-11, 1993, Tucson,
 Arizona.
 
 Language:  English
 
 Descriptors: Poa pratensis; Herbicides; Tolerance
 
 
 313                                NAL Call. No.: 100 L93 (3)
 Tolerance of rice varieties and experimental lines to rice
 herbicides. Sanders, D.E.; Linscombe, S.D.; Jodari, F.;
 Fabacher, A.P. Crowley, La. : The Station, 1986-; 1992.
 Annual research report / (84th): p. 89-95; 1992.
 
 Language:  English
 
 Descriptors: Oryza sativa; Varieties; Herbicide resistance;
 Application rates; Crop yield
 
 
 314                                  NAL Call. No.: SB610.W39
 Tolerance of three annual forage legumes to selected
 postemergence herbicides. Evers, G.W.; Grichar, W.J.; Pohler,
 C.L.; Schubert, A.M.
 Champaign, Ill. : The Weed Science Society of America; 1993
 Jul. Weed technology : a journal of the Weed Science Society
 of America v. 7 (3): p. 735-739; 1993 Jul.  Includes
 references.
 
 Language:  English
 
 Descriptors: Texas; Cabt; Trifolium alexandrinum; Trifolium
 subterraneum; Trifolium hirtum; Fodder legumes; Weed control;
 Chemical control; Tolerance; Bentazone; 2,4-d; Propyzamide;
 Phytotoxicity; Crop damage; Abiotic injuries; Herbicide
 resistance; Species differences
 
 
 315                                  NAL Call. No.: 79.8 W412
 Tolerance of triazine-resistant and susceptible biotypes of
 three weeds to heat stress: a fluorescence study.
 Fuks, B.; Eycken, F. van; Lannoye, R.
 Oxford : Blackwell Scientific Publications; 1992 Feb.
 Weed research v. 32 (1): p. 9-17; 1992 Feb.  Includes
 references.
 
 Language:  English
 
 Descriptors: Solanum nigrum; Poa annua; Chenopodium album;
 Herbicide resistant weeds; Susceptibility; Biotypes; Heat
 stress; Heat tolerance; Chlorophyll; Fluorescence; Plant
 physiology
 
 
 316                                   NAL Call. No.: 450 P692
 Tolerance to imidazolinone herbicides in wheat.
 Newhouse, K.E.; Smith, W.A.; Starrett, M.A.; Schaefer, T.J.;
 Singh, B.K. Rockville, MD : American Society of Plant
 Physiologists, 1926-; 1992 Oct. Plant physiology v. 100 (2):
 p. 882-886; 1992 Oct.  Includes references.
 
 Language:  English
 
 Descriptors: Triticum aestivum; Imazethapyr; Herbicide
 resistance; Induced mutations; Mutants; Genes; Inheritance;
 Segregation; Oxo-acid-lyases; Enzyme activity; Allelism
 
 Abstract:  An imidazolinone-tolerant wheat (Triticum aestivum
 L. em Thell) mutant in the winter wheat cultivar Fidel has
 been identified and characterized. The mutant was isolated
 from a population derived through seed mutagenesis of the
 variety with an aqueous solution containing sodium azide.
 Imidazolinone-tolerant wheat seedlings were selected from the
 generation of the population in the presence of imazethapyr
 herbicide and identified as herbicide-insensitive individuals.
 The trait is inherited as a single semidominant gene and
 confers high levels of tolerance to imazethapyr.
 Acetohydroxyacid synthase activity in extracts from
 imidazolinone-tolerant plants was less inhibited by
 imazethapyr than the enzyme from the wild type. The herbicide-
 tolerant plants have a completely normal phenotype and display
 no negative effects on growth and yield in either the absence
 or presence of imazethapyr.
 
 
 317                                   NAL Call. No.: 23 AU792
 Tolerances of canola, field pea, lupin and faba bean cultivars
 to herbicides. Lemerle, D.; Hinkley, R.B.
 East Melbourne : Commonwealth Scientific and Industrial
 Research Organization; 1991.
 Australian journal of experimental agriculture v. 31 (3): p.
 379-386; 1991. Includes references.
 
 Language:  English
 
 Descriptors: New South Wales; Brassica campestris; Brassica
 napus; Lupinus albus; Lupinus angustifolius; Pisum sativum;
 Vicia faba; Cultivars; Herbicide resistance; Herbicides;
 Injuries; Phytotoxicity; Site factors; Weed control; Yield
 losses; Yield response functions
 
 
 318                                   NAL Call. No.: 450 P692
 Transformation and regeneration of two cultivars of pea (Pisum
 sativum L.). Schroeder, H.E.; Schotz, A.H.; Wardley-
 Richardson, T.; Spencer, D.; Higgins, T.J.V.
 Rockville, MD : American Society of Plant Physiologists, 1926-
 ; 1993 Mar. Plant physiology v. 101 (3): p. 751-757; 1993 Mar. 
 Includes references.
 
 Language:  English
 
 Descriptors: Pisum sativum; Agrobacterium tumefaciens; Genetic
 transformation; Transgenic plants; Gene transfer; Reporter
 genes; Phosphotransferases; Acyltransferases; Recombinant 
 DNA; Regenerative ability; Tissue culture; Herbicide
 resistance; Glufosinate; Genetic markers; Explants; Plant
 embryos
 
 Abstract:  A reproducible transformation system was developed
 for pea (Pisum sativum L.) using as explants sections from the
 embryonic axis of immature seeds. A construct containing two
 chimeric genes, nopaline synthase-phosphinothricin acetyl
 transferase (bar) and cauliflower mosaic virus 35S-neomycin
 phosphotransferase (nptII), was introduced into two pea
 cultivars using Agrobacterium tumefaciens-mediated
 transformation procedures. Regeneration was via organogenesis,
 and transformed plants were selected on medium containing 15
 mg/L of phosphinothricin. Transgenic peas were raised in the
 glasshouse to produce flowers and viable seeds. The bar and
 nptII genes were expressed in both the primary transgenic pea
 plants and in the next generation progeny, in which they
 showed a typical 3:1 Mendelian inheritance pattern.
 Transformation of regenerated plants was confirmed by assays
 for neomycin phosphotransferase and phosphinothricin acetyl
 transferase activity and by northern blot analyses.
 Transformed plants were resistant to the herbicide Basta when
 sprayed at rates used in field practice.
 
 
 319                             NAL Call. No.: S494.5.B563B56
 Transformation in Linum usitatissimum L. (flax).
 Jordan, M.C.; McHughen, A.
 Berlin, W. Ger. : Springer-Verlag; 1993.
 Biotechnology in agriculture and forestry v. 22: p. 244-252;
 1993.  In the series analytic: Plant protoplasts and genetic
 engineering III / edited by Y.P.S. Bajaj.  Includes
 references.
 
 Language:  English
 
 Descriptors: Linum usitatissimum; Genetic transformation;
 Agrobacterium tumefaciens; Transgenic plants; Herbicide
 resistance; Glyphosate; Glufosinate; Gene transfer;
 Sulfonylurea herbicides; Regenerative ability
 
 
 320                                   NAL Call. No.: QH442.B5
 Transformation of sugarbeet (Beta vulgaris L.) and evaluation
 of herbicide resistance in transgenic plants.
 D'Halluin, K.; Bossut, M.; Bonne, E.; Mazur, B.; Leemans, J.;
 Botterman, J. New York, N.Y. : Nature Publishing Company; 1992
 Mar.
 Bio/technology v. 10 (3): p. 309-314; 1992 Mar.  Includes
 references.
 
 Language:  English
 
 Descriptors: Beta vulgaris var. saccharifera; Agrobacterium
 tumefaciens; Genetic transformation; Transgenics; Gene
 transfer; Genes; Bilanafos; Ligases; Glufosinate; Sulfonylurea
 herbicides; Herbicide resistance; Acyltransferases
 
 
 321                                  NAL Call. No.: QK725.P54
 Transgenic herbicide-resistant Atropa belladonna using an Ri
 binary vector and inheritance of the transgenic trait.
 Saito, K.; Tamazaki, M.; Anzai, H.; Yoneyama, K.; Murakoshi,
 I. Berlin, W. Ger. : Springer International; 1992.
 Plant cell reports v. 11 (5/6): p. 219-224; 1992.  Includes
 references.
 
 Language:  English
 
 Descriptors: Atropa belladonna; Transgenics; Gene transfer;
 Genetic transformation; Herbicide resistance; Bilanafos;
 Glufosinate; Inheritance; Agrobacterium rhizogenes; Enzyme
 activity; Cauliflower mosaic caulimovirus; Transferases
 
 Abstract:  Transgenic Atropa belladonna conferred with a
 herbicide-resistant trait was obtained by transformation with
 an Ri plasmid binary vector and plant regeneration from hairy
 roots. We made a chimeric construct, pARK5, containing the bar
 gene encoding phosphinothricin acetyltransferase flanked with
 the promoter for cauliflower mosaic virus 35S RNA and the 3'
 end of the nos gene. Leaf discs of A. belladonna were infected
 with Agrobacterium rhizogenes harboring an Ri plasmid,
 pRi15834, and pARK5. Transformed hairy roots resistant to
 bialaphos (5 mg/l) were selected and plantlets were
 regenerated. The integration of T-DNAs from pRi15834 and pARK5
 were confirmed by DNA-blot hybridization. Expression of the
 bar gene in transformed R0 tissues and in backcrossed F1
 progeny with a non-transformant and self-fertilized progeny
 was indicated by enzymatic activity of the acetyltransferase.
 The transgenic plants showed resistance towards bialaphos and
 phosphinothricin. Tropane alkaloids of normal amounts were
 produced in the transformed regenerants. These results present
 a successful application of transformation with an Ri plasmid
 binary vector for conferring an agronomically useful trait to
 medicinal plants.
 
 
 322                                   NAL Call. No.: 450 P693
 Transgenic plants containing the phosphinothricin-N-
 acetyltransferase gene metabolize the herbicide L-
 phosphinothricin (glufosinate) differently from untransformed
 plants.
 Droge, W.; Broer, I.; Puhler, A.
 Berlin : Springer-Verlag; 1992.
 Planta v. 187 (1): p. 142-151; 1992.  Includes references.
 
 Language:  English
 
 Descriptors: Nicotiana tabacum; Daucus carota; Agrobacterium
 tumefaciens; Transgenics; Glufosinate; Metabolism;
 Transferases; Enzyme activity; Genetic code; Nucleotide
 sequences
 
 Abstract:  L-Phosphinothricin (L-Pt)-resistant plants were
 constructed by introducing a modified phosphinothricin-N-
 acetyl-transferase gene (pat) via Agrobacterium-mediated gene
 transfer into tobacco (Nicotiana tabacum L), and via direct
 gene transfer into carrot (Daucus carota L). The metabolism of
 L-Pt was studied in these transgenic, Pt-resistant plants, as
 well as in the untransformed species. The degradation of L-Pt,
 14C-labeled specifically at different C-atoms, was analysed by
 measuring the release of 14CO2 and by separating the labeled
 degradation products on thin-layer-chromatography plates. In
 untransformed tobacco and carrot plants, L-Pt was deaminated
 to form its corresponding oxo acid 4-methylphosphinico-2-oxo-
 butanoic acid (PPO), which subsequently was decarboxylated to
 form 3-methylphosphinico-propanoic acid (MPP). This compound
 was stable in plants. A third metabolite remained
 unidentified. The L-Pt was rapidly N-acetylated in herbicide-
 resistant tobacco and carrot plants, indicating that the
 degradation pathway of L-Pt into PPO and MPP was blocked. The
 N-acetylated product, L-N-acetyl-Pt remained stable with
 regard to degradation, but was found to exist in a second
 modified form. In addition, there was a pH-dependent,
 reversible change in the mobility of L-N-acetyl-Pt thin-layer
 during chromatography.
 
 
 323                                   NAL Call. No.: QH442.B5
 Transgenic plants of tall fescue (Festuca arundinacea Schreb.)
 obtained by direct gene transfer to protoplasts.
 Wang, Z.Y.; Takamizo, T.; Iglesias, V.A.; Osusky, M.; Nagel,
 J.; Potrykus, I.; Spangenberg, G.
 New York, N.Y. : Nature Publishing Company; 1992 Jun.
 Bio/technology v. 10 (6): p. 691-696; 1992 Jun.  Includes
 references.
 
 Language:  English
 
 Descriptors: Festuca arundinacea; Genetic transformation;
 Transgenics; Protoplasts; Gene transfer; Direct  DNAuptake;
 Reporter genes; Phosphotransferases; Acyltransferases; Cell
 suspensions; In vitro selection; Hygromycin b; Glufosinate;
 Drug resistance; Herbicide resistance; Callus; Embryogenesis;
 Regenerative ability
 
 
 324                                   NAL Call. No.: 500 N21P
 Transgenic sorghum plants via microprojectile bombardment.
 Casas, A.M.; Kononowicz, A.K.; Zehr, U.B.; Tomes, D.T.;
 Axtell, J.D.; Butler, L.G.; Bressan, R.A.; Hasegawa, P.M.
 Washington, D.C. : National Academy of Sciences,; 1993 Dec01.
 Proceedings of the National Academy of Sciences of the United
 States of America v. 90 (23): p. 11212-11216; 1993 Dec01. 
 Includes references.
 
 Language:  English
 
 Descriptors: Sorghum bicolor; Transgenics; Cultivars; Gene
 transfer; Genetic transformation; Genotypes; Herbicide
 resistance; Tissue culture; Transferases; Beta-glucuronidase;
 Enzyme activity
 
 Abstract:  Transgenic sorghum plants have been obtained after
 microprojectile bombardment of immature zygotic embryos of a
 drought-resistant sorghum cultivar, P898012. DNA delivery
 parameters were optimized based on transient expression of R
 and C1 maize anthocyanin regulatory elements in scutellar
 cells. The protocol for obtaining transgenic plants consists
 of the delivery of the bar gene to immature zygotic embryos
 and the imposition of bialaphos selection pressure at various
 stages during culture, from induction of somatic embryogenesis
 to rooting of regenerated plantlets. One in about every 350
 embryos produced embryogenic tissues that survived bialaphos
 treatment; six transformed callus lines were obtained from
 three of the eight sorghum cultivars used in this research.
 Transgenic (T0) plants were obtained from cultivar P898012
 (two independent transformation events). The presence of the
 bar and uidA genes in the T0 plants was confirmed by Southern
 blot analysis of genomic DNA. Phosphinothricin
 acetyltransferase activity was detected in extracts of the T0
 plants. These plants were resistant to local application of
 the herbicide Ignite/Basta, and the resistance was inherited
 in T1 plants as a single dominant locus.
 
 
 325                                   NAL Call. No.: 79.8 W41
 Translocation of glyphosate, quizalofop, and sucrose in
 quackgrass (Elytrigia repens) biotypes.
 Tardif, F.J.; Leroux, G.D.
 Champaign, Ill. : Weed Science Society of America; 1993 Jul.
 Weed science v. 41 (3): p. 341-346; 1993 Jul.  Includes
 references.
 
 Language:  English
 
 Descriptors: Elymus repens; Biotypes; Herbicide resistance;
 Herbicide resistant weeds; Glyphosate; Quizalofop;
 Translocation; Rhizomes; Sucrose; Uptake; Stable isotopes;
 Spatial distribution; Systemic action; Perennial weeds; Weed
 control; Chemical control
 
 Abstract:  The translocation pattern and distribution in
 rhizomes of 14C-glyphosate, 14C-quizalofop, and 14C-sucrose
 was examined in five quackgrass biotypes. Translocation of
 radioactivity in the different plant parts varied among
 biotypes. Translocation in the whole plant after treatment
 with the three 14C-chemicals varied among biotypes but was not
 correlated with their tolerance to herbicides. Detailed
 analysis of distribution of radioactivity in the primary
 rhizome showed that more 14C was found in the apical sections
 after treatment with 14C-sucrose. A similar pattern was
 observed after 14C-glyphosate application with all biotypes
 except one. Very low radioactivity was found in rhizomes after
 14C-quizalofop application, but a preferential accumulation in
 apical sections of the primary rhizome was detected in two
 biotypes. The tolerance of one biotype to glyphosate was
 explained by the absence of radioactivity accumulation in the
 apical sections of the rhizome.
 
 
 326                                  NAL Call. No.: SB610.W39
 Triazine-resistant common lambsquarters (Chenopodium album L.)
 control in field corn (Zea mays L.).
 Myers, M.G.; Harvey, R.G.
 Champaign, Ill. : The Weed Science Society of America; 1993
 Oct. Weed technology : a journal of the Weed Science Society
 of America v. 7 (4): p. 884-889; 1993 Oct.  Includes
 references.
 
 Language:  English
 
 Descriptors: Wisconsin; Cabt; Zea mays; Weed control;
 Herbicide resistant weeds; Chenopodium album; Triazine
 herbicides; Chemical control; Application date; Timing;
 Acetochlor; Alachlor; Atrazine; Bentazone; Bromoxynil;
 Cyanazine; Dicamba; Metolachlor; Pendimethalin; Pyridate;
 Sulfonylurea herbicides; Tridiphane; 2,4-d; Amines;
 Application rates; Efficacy
 
 
 327                                  NAL Call. No.: SB610.W39
 Triazine-resistant smooth pigweed (Amaranthus hybridus)
 control in field corn (Zea mays L.).
 Birschbach, E.D.; Myers, M.G.; Harvey, R.G.
 Champaign, Ill. : The Weed Science Society of America; 1993
 Apr. Weed technology : a journal of the Weed Science Society
 of America v. 7 (2): p. 431-436; 1993 Apr.  Includes
 references.
 
 Language:  English
 
 Descriptors: Wisconsin; Cabt; Zea mays; Weed control; Chemical
 control; Amaranthus hybridus; Herbicide resistance; Herbicide
 resistant weeds; Atrazine; Metribuzin; Herbicide mixtures;
 Dicamba; Alachlor; Acetochlor; Pyridate; Bentazone; Cyanazine;
 2,4-d; Linuron; Simazine; Sulfonylurea herbicides;
 Pendimethalin; Tridiphane; Application rates; Application
 date; Timing
 
 
 328                                    NAL Call. No.: 450 C16
 Tribute summer rape.
 Rakow, G.; Downey, R.K.
 Ottawa : Agricultural Institute of Canada; 1993 Jan.
 Canadian journal of plant science; Revue canadienne de
 phytotechnie v. 73 (1): p. 189-191; 1993 Jan.  Includes
 references.
 
 Language:  English
 
 Descriptors: Saskatchewan; Brassica napus; Breeding methods;
 Crop yield; Cultivars; Herbicide resistance
 
 
 329                                   NAL Call. No.: 450 P693
 Tubulin-isotype analysis of two grass species-resistant to
 dinitroaniline herbicides.
 Waldin, T.R.; Ellis, J.R.; Hussey, P.J.
 Berlin : Springer-Verlag; 1992.
 Planta v. 188 (2): p. 258-264; 1992.  Includes references.
 
 Language:  English
 
 Descriptors: Eleusine indica; Setaria viridis; Trifluralin;
 Herbicide resistance; Cross resistance; Dinitroaniline
 herbicides; Diagnostic techniques; Tubulin; Chemical
 composition; Protein content; Protein composition
 
 Abstract:  Trifluralin-resistant biotypes of Eleusine indica
 (L.) Gaertn. (goosegrass) and Setaria viridis (L.) Beauv.
 (green foxtail) exhibit cross-resistance to other
 dinitroaniline herbicides. Since microtubules are considered
 the primary target site for dinitroaniline herbicides we
 investigated whether the differential sensitivity of resistant
 and susceptible biotypes of these species results from
 modified tubulin polypeptides. One-dimensional and two-
 dimensional polyacrylamide gel electrophoresis combined with
 immunoblotting using well-characterised anti-tubulin
 monoclonal antibodies were used to display the family of
 tubulin isotypes in each species. Seedlings of E. indica
 exhibited four beta-tubulin isotypes and one alpha-tubulin
 isotype, whereas those of S. viridis exhibited two beta-
 tubulin and two alpha-tubulin isotypes. Comparison of the
 susceptible and resistant biotypes within each species
 revealed no differences in electrophoretic properties of the
 multiple tubulin isotypes. These results provide no evidence
 that resistance to dinitroaniline herbicides is associated
 with a modified tubulin polypeptide in these biotypes of E.
 indica or S. viridis.
 
 
 330                                   NAL Call. No.: 470 C16C
 Ultrastructure of Chlamydomonas reinhardtii following exposure
 to paraquat: comparison of wild type and a paraquat-resistant
 mutant.
 Bray, D.F.; Bagu, J.R.; Nakamura, K.
 Ottawa, Ont. : National Research Council of Canada; 1993 Jan.
 Canadian journal of botany; Journal canadien de botanique v.
 71 (1): p. 174-182; 1993 Jan.  Includes references.
 
 Language:  English
 
 Descriptors: Chlamydomonas reinhardtii; Paraquat;
 Phytotoxicity; Herbicide resistance; Mutants; Genes;
 Inheritance; Ultrastructure; Mitochondria; Thylakoids;
 Chloroplasts; Nuclei; Methionine; Resistance
 
 
 331                                  NAL Call. No.: 79.8 W412
 Uptake and efflux of chlorimuron ethyl by excised soybean
 (Glycine max (L.) Merr.) root tissue.
 Nandihalli, U.B.; Bhowmik, P.C.
 Oxford : Blackwell Scientific Publications; 1991 Oct.
 Weed research v. 31 (5): p. 295-300; 1991 Oct.  Includes
 references.
 
 Language:  English
 
 Descriptors: Glycine max; Roots; Uptake; Chlorimuron;
 Radioactive tracers; Herbicide resistance; Susceptibility
 
 
 332                                  NAL Call. No.: SB610.W39
 Uptake, translocation, and metabolism of chlorimuron in
 soybean (Glycine max) and morningglory (Ipomoea spp.).
 Moseley, C.; Hatzios, K.K.; Hagood, E.S.
 Champaign, Ill. : The Weed Science Society of America; 1993
 Apr. Weed technology : a journal of the Weed Science Society
 of America v. 7 (2): p. 343-348; 1993 Apr.  Includes
 references.
 
 Language:  English
 
 Descriptors: Glycine max; Cultivars; Varietal susceptibility;
 Ipomoea lacunosa; Pharbitis hederacea; Chlorimuron; Uptake;
 Translocation; Metabolism; Herbicide resistance; Growth rate;
 Absorption; Phytotoxicity; Crop damage; Weed control; Chemical
 control
 
 
 333                                  NAL Call. No.: 79.8 W412
 Uptake, translocation and phytotoxicity of root-absorbed
 haloxyfop in soybean, Festuca rubra L. and Festuca arundinacea
 Schreb.
 Aguero-Alvarado, R.; Appleby, A.P.
 Oxford : Blackwell Scientific Publications; 1991 Oct.
 Weed research v. 31 (5): p. 257-263; 1991 Oct.  Includes
 references.
 
 Language:  English
 
 Descriptors: Festuca rubra; Festuca arundinacea; Glycine max;
 Haloxyfop; Phytotoxicity; Roots; Uptake; Absorption;
 Translocation; Herbicide resistance; Susceptibility; Growth
 rate; Radioactive tracers
 
 
 334                                     NAL Call. No.: A00109
 USDA scientist develops herbicide-tolerant potatoes.
 Washington, DC : National Biotechnology Policy Center of the
 National Wildlife Federation; 1991 Jun.
 The gene exchange v. 2 (2): p. 7; 1991 Jun.
 
 Language:  English
 
 Descriptors: U.S.A.; Field tests; Biotechnology; Usda; Plants
 
 
 335                                  NAL Call. No.: QK710.P62
 Use of bar as a selectable marker gene and for the production
 of herbicide-resistant rice plants from protoplasts.
 Rathore, K.S.; Chowdhury, V.K.; Hodges, T.K.
 Dordrecht : Kluwer Academic Publishers; 1993 Mar.
 Plant molecular biology : an international journal on
 molecular biology, biochemistry and genetic engineering v. 21
 (5): p. 871-884; 1993 Mar. Includes references.
 
 Language:  English
 
 Descriptors: Oryza sativa; Streptomyces; Genetic
 transformation; Transgenic plants; Protoplasts; Direct 
 DNAuptake; Gene transfer; Structural genes; Acyltransferases;
 Glufosinate; Herbicide resistance; In vitro selection; Marker
 genes; Reporter genes; Beta-glucuronidase
 
 Abstract:  We have used the bar gene in combination with the
 herbicide Basta to select transformed rice (Oryza sativa L.
 cv. Radon) protoplasts for the production of herbicide-
 resistant rice plants. Protoplasts, obtained from regenerable
 suspension cultures established from immature embryo callus,
 were transformed using PEG-mediated DNA uptake. Transformed
 calli could be selected 2-4 weeks after placing the
 protoplast-derived calli on medium containing the selective
 agent, phosphinothricin (PPT), the active component of Basta.
 Calli resistant to PPT were capable of regenerating plants.
 Phosphinothricin acetyltransferase (PAT) assays confirmed the
 expression of the bar gene in plants obtained from PPT-
 resistant calli. The only exceptions were two plants obtained
 from the same callus that had multiple copies of the bar gene
 integrated into their genomes. The transgenic status of the
 plants was varified by Southern blot analysis. In our system,
 where the transformation was done via the protoplast method,
 there were very few escapes. The efficiency of co-
 transformation with a reporter gene gusA, was 30%. The T0
 plants of Radon were self-fertile. Both the bar and gusA genes
 were transmitted to progeny as confirmed by Southern analysis.
 Both genes were expressed in T1 and T2 progenies. Enzyme
 analyses on T1 progeny plants also showed a gene dose response
 reflecting their homozygous and heterozygous status. The
 leaves of T0 plants and that of the progeny having the bar
 gene were resistant to application of Basta. Thus, the bar
 gene has proven to be a useful selectable and screenable
 marker for the transformation of rice plants and for the
 production of herbicide-resistant plants.
 
 
 336                                   NAL Call. No.: QK710.A9
 The use of the Emu promoter with antibiotic and herbicide
 resistance genes for the selection of transgenic wheat callus
 and rice plants. Chamberlain, D.A.; Brettell, R.I.S.; Last,
 D.I.; Witrzens, B.; McElroy, D.; Dolferus, R.; Dennis, E.S.
 Melbourne, Commonwealth Scientific and Industrial Research
 Organization; 1994. Australian journal of plant physiology v.
 21 (1): p. 95-112; 1994.  Includes references.
 
 Language:  English
 
 Descriptors: Triticum aestivum; Oryza sativa; Gene transfer;
 Transgenic plants; Callus; Gene expression; Selection; Marker
 genes; Leaves; Enzyme activity; Promoters
 
 
 337                                  NAL Call. No.: SB951.P47
 Using chlorophyll fluorescence induction for a quantitative
 detoxification assay with metribuzin and chlorotoluron in
 excised wheat (triticum aestivum and Triticum durum) leaves.
 Ducruet, J.M.; Sixto, H.; Garcia-Baudin, J.M.
 Sussex : John Wiley and Sons Limited; 1993.
 Pesticide science v. 38 (4): p. 295-301; 1993.  Includes
 references.
 
 Language:  English
 
 Descriptors: Metribuzin; Chlorotoluron; Triticum aestivum;
 Triticum durum; Cultivars; Susceptibility; Herbicide
 resistance; Root treatment; Leaves; Translocation; Metabolic
 detoxification; Kinetics; Fluorescence; Induction; Dark;
 Incubation; Duration; Temperature; Photosystem ii; Inhibition;
 Quantitative techniques
 
 Abstract:  Chlorophyll fluorescence induction was used as a
 probe to detect herbicide detoxification in tolerant or
 susceptible wheat cultivars. Experimental conditions have been
 carefully examined for establishing detoxification kinetics of
 chlorotoluron and metribuzin, two photosystem-II-inhibiting
 herbicides. After a root treatment, leaves were cut, placed in
 glass tubes and maintained in the dark. The fluorescence
 induction rise was examined repeatedly and detoxification
 kinetics were established from these data for the same
 position on the individual leaves. The herbicide-dependent
 fluorescence rise decreased within hours in chlorotoluron-
 tolerant but not in susceptible Triticum aestivum cultivars.
 In contrast, no significant reversion could be detected after
 metribuzin application in both tolerant and susceptible
 cultivars of Triticum durum. Near the fluorescence-determined
 half-inhibition of photosystem II, linear detoxification
 kinetics were obtained in individual leaves, thus providing an
 accurate measurement of relative detoxification rates.
 
 
 338                                  NAL Call. No.: SB610.W39
 Varietal tolerance of rice (Oryza sativa) to bromoxynil and
 triclopyr at different growth stages.
 Pantone, D.J.; Baker, J.B.
 Champaign, Ill. : The Weed Science Society of America; 1992
 Oct. Weed technology : a journal of the Weed Science Society
 of America v. 6 (4): p. 968-974; 1992 Oct.  Includes
 references.
 
 Language:  English
 
 Descriptors: Louisiana; Cabt; Oryza sativa; Cultivars;
 Herbicide resistance; Varietal tolerance; Bromoxynil;
 Triclopyr; Application rates; Crop growth stage; Crop damage;
 Crop yield
 
 
 339                                  NAL Call. No.: QH301.A76
 Vegetation management during establishment of farm woodlands.
 Williamson, D.R.; MacDonald, H.G.; Nowakowski, M.R.
 Wellesbourne, Warwick : The Association of Applied Biologists;
 1992. Aspects of applied biology (29): p. 203-210; 1992.  In
 the series analytic: Vegetation management in forestry,
 amenity and conservation areas. Paper presented at the
 conference of the Association, April 7-9, 1992, University of
 York, England.  Includes references.
 
 Language:  English
 
 Descriptors: England; Farm woodlands; Trees; Weed control;
 Establishment; Ground cover plants; Herbicide residues;
 Herbicide resistance; Screening; Survival; Vegetation
 management
 
 
 340                                  NAL Call. No.: SB610.W39
 Weed control in oat (Avena sativa)-alfalfa (Medicago sativa)
 and effect on next year corn (Zea mays) yield.
 Moomaw, R.S.
 Champaign, Ill. : The Weed Science Society of America; 1992
 Oct. Weed technology : a journal of the Weed Science Society
 of America v. 6 (4): p. 871-877; 1992 Oct.  Includes
 references.
 
 Language:  English
 
 Descriptors: Nebraska; Cabt; Avena sativa; Medicago sativa;
 Zea mays; Herbicide resistance; Rotations; No-tillage; Weed
 control; Herbicides; Crop density; Crop yield; Drought
 
 
 341                                  NAL Call. No.: SB610.W39
 Weed thresholds: the space component and considerations for
 herbicide resistance.
 Maxwell, B.D.
 Champaign, Ill. : The Society; 1992 Jan.
 Weed technology : a journal of the Weed Science Society of
 America v. 6 (1): p. 205-212; 1992 Jan.  Paper presented at
 the "Symposium on Ecological Perspectives on Utility of
 Thresholds for Weed Management," February 5, 1991. Includes
 references.
 
 Language:  English
 
 Descriptors: Weeds; Economic thresholds; Weed control;
 Herbicide resistance; Herbicide resistant weeds; Population
 dynamics; Seeds; Dispersal; Weed biology; Crop yield; Yield
 losses; Mathematical models; Triticum aestivum; Setaria
 viridis; Simulation models
 
 
 342                                     NAL Call. No.: SB1.H6
 Wildflower tolerance to metolachlor and metolachlor combined
 with other broadleaf herbicides.
 Derr, J.F.
 Alexandria, Va. : The American Society for Horticultural
 Science; 1993 Oct. HortScience : a publication of the American
 Society for Horticultural Science v. 28 (10): p. 1023-1026;
 1993 Oct.  Includes references.
 
 Language:  English
 
 Descriptors: Coreopsis; Leucanthemum vulgare; Echinacea
 purpurea; Gaillardia; Stand establishment; Weed control;
 Chemical control; Herbicide resistance; Site preparation;
 Metolachlor; Herbicide mixtures; Isoxaben; Oxadiazon;
 Simazine; Phytotoxicity; Abiotic injuries; Efficacy; Eclipta
 alba; Cyperus esculentus
 
 Abstract:  The tolerance of transplanted lanceleaf coreopsis
 (Coreopsis lanceolata L.), ox-eye daisy (Chrysanthemum
 leucantheum L.), purple coneflower [Echinaea purpurea (L.)
 Moench.], and blanket flower (Gaiuardia aristata Pursh) to
 metolachlor was determined in field trials.Metolachlor at 4.5
 kg.ha-1 (maximum use rate) and 9.0 kg.ha-1 (twice the maximum
 use rate) did not reduce stand or flowering of any wildflower
 species after one or two applications, although plants
 developed transient visible injury. Combining metolachlor with
 the broadleaf herbicides simazine or isoxaben resulted in
 unacceptable injury and stand reduction, especially in ox-eye
 daisy. Metolachlor plus oxadiazon was less injurious to the
 wildflowers than metolachlor plus either simazine or isoxaben.
 Treatments containing metolachlor controlled yellow nutsedge
 (Cyperus escukntus L.) by at least 89% in both experiments.
 Treatments containing isoxaben controlled eclipta (Ecupta alba
 L.) 100% in both studies.
 
 
 
                          AUTHOR INDEX
 
 Abdel-Meguid, S.S. 299
 Acquaah, G. 217
 Adam, G. 150
 Aguero-Alvarado, R. 333
 Ahmad, I. 137
 Al-Henaid, J. 254
 Al-Khatib, K. 78, 309
 Alam, S.M.M. 103
 Alcocer-Ruthling, M. 73, 216, 285
 Aliev, K.A. 44
 Allen, R.D. 177
 Amrheim, N. 132
 Amsellem, Z. 70
 Anderson, J.J. 209
 Anderson, J.M. 95
 Anderson, K.S. 299
 Anderson, M.P. 12, 23
 Anderson, T.R. 139
 Annamalai, P. 66
 Anzai, H. 27, 321
 Appleby, A.P. 51, 333
 Arad, S.M. 268
 Armour, S.L. 144
 Armstrong-Gustafson, P. 61
 Astier, C. 117
 Atkin, R. K. 147
 Auld, D.L. 69
 Australia 24
 Aviv, D. 99
 Axtell, J.D. 324
 Baerg, R.J. 200
 Bagrova, A.M. 17
 Bagu, J.R. 330
 Bailey, J.A. 22
 Baker, J.B. 338
 Balke, N.E. 3, 39
 Bandaranayake, Hema Anura Divale 182
 Barak, Z. 268
 Barrentine, W.L. 80, 142, 149, 296
 Baszczynski, C. 141
 Bauer-Weston, B. 248
 Baum, R.M. 163
 Bayley, C. 96
 Beaty, Jackie Dwayne 282
 Becerril, J.M. 239
 Beck, C.I. 32
 Beckie, H.J. 85, 89
 Beiles, A. 155
 Belliard, G. 28, 126, 178
 Benoit, D.L. 257
 Bensch, C. 12
 Benveniste, P. 28, 126, 178
 Benyamini, Y. 76, 195
 Betts, K.J. 200, 201
 Bewick, T.A. 14, 298, 305
 Bhargava, S. 237
 Bhowmik, P.C. 331
 Birschbach, E.D. 327
 Bjelk, L.A. 202
 Block, M. de 25
 Boerboom, C.M. 263
 Boger, P. 110, 240
 Bonne, E. 320
 Borough, C. 43
 Bossut, M. 320
 Botterman, J. 25, 320
 Bottino, P. J. 192
 Boudry, P. 230
 Boutsalis, P. 274
 Bouyoub, A. 117
 Boyd, P.A. 64
 Boydston, R.A. 309
 Bradley, D. 127
 Bradley, J.R. Jr 175
 Brandle, J.E. 11, 276
 Bray, D.F. 330
 Bregeon, M. 37
 Breiland, K. 208
 Brendel, M. 121
 Bressan, R.A. 324
 Brettell, R.I.S. 336
 Brewer, C.H. 4
 Brewster, B.D. 51
 Britt, C.P. 269
 Broer, I. 170, 189, 322
 Brown, D. 218
 Buchanan-Wollaston, V. 242
 Buhler, D.D. 3
 Burke, J.J. 177
 Burmester, R.G. 243
 Burnet, M.W.M. 16, 176
 Burnside, O.C. 262
 Burton, J.D. 134, 272
 Bushnell, W.R. 112
 Butler, L.G. 324
 Buxton, J. 81
 Buzzell, R.I. 139
 Byrd, J.D. Jr 149
 Cabanne, F. 291
 Caddel, J.L. 12
 Cakmak, I. 199
 Callihan, R.H. 159
 Cannon, F. 242
 Cantliffe, D.J. 298
 Cao, J. 264
 Caponetti, J.D. 281
 Carey, C.K. 50
 Carrow, R.N. 115
 Casas, A.M. 324
 Caseley, J. C. 147
 Castillo, A.M. 152, 261
 Catanzaro, C.J. 134, 272
 Chakravarty, K.S. 49
 Chamberlain, D.A. 336
 Chamovitz, D. 215
 Chase, C. 82
 Chee, P.W. 259
 Cheung, W.Y. 257
 Chevre, A.M. 191
 Chipman, D.M. 268
 Chow, W.S. 95
 Chowdhury, M.K.U. 297
 Chowdhury, V.K. 335
 Christensen, A.H. 27
 Christianson, M.L. 116
 Christopher, J.T. 56, 273
 Chun, P.T. 187
 Chupeau, Y. 9
 Clay, D.V. 22, 107
 Claypool, P.L. 136
 Coggins, J.R. 252
 Coghlan, A. 212
 Cohen, Z. 165, 233
 Collins, W.K. 175
 Colvin, D.L. 35
 Comstock, G. 47, 102
 Conroy, D. 31
 Cooke, D.T. 90
 Cooke, R. 227
 Corbin, F.T. 175
 Corio-Costet, M.F. 92, 93
 Cote, J.C. 257
 Cotterman, J.C. 260, 304
 Cottingham, C.K. 26
 Coupland, D. 90, 94
 Crawford, S.H. 234
 Crawley, M.J. 81
 Croft, P.H. 74
 Cseke, C. 196
 Curran, W.S. 140
 Cussans, G. W. 147
 Cutler, K. 55
 D'Halluin, K. 25, 320
 Dall'Agnese, M. 92
 Datta, K. 164
 Datta, S.K. 164
 Davis, D.G. 208
 Davis, E.S. 104
 Day, J.P. 137
 Dayringer, H.E. 299
 Dekker, J. 102, 219
 Dekker, J.H. 243, 266
 Delmer, Deborah P. 181
 Denecke, J. 25
 Dennis, E.S. 336
 Derr, J.F. 311, 342
 Devine, M.D. 40, 41, 71, 146, 188, 193, 277
 Dial, M.J. 173, 312
 Dias, J.M. 5
 Dickman, M.B. 289
 Didi, S. 233
 DiMaio, J.J. 144
 DiTomaso, J.M. 91, 207
 Dixon, F.L. 158
 Dodge, A.D. 206
 Doley, W.P. 217
 Dolferus, R. 336
 Dominguez, C. 224
 Donaldson, W.S. 51
 Donn, G. 97, 164
 Dons, J.J.M. 287
 Doohan, D.J. 86
 Dotray, P.A. 91
 Dotray, P.D. 13
 Downey, R.K. 10, 328
 Draber, W. 302
 Driesenaar, A.R.J. 70, 251
 Droge, W. 189, 322
 Duan, X.L. 264
 Ducruet, J.M. 19, 337
 Dudler, R. 300
 Duke, M.V. 239
 Duke, S.O. 29, 204, 239, 245
 Dusky, J.A. 254, 298
 Dutcher, S.K. 124
 Duvick, D.N. 48
 Dyer, W.E. 21, 104, 245, 259
 Eber, F. 191
 Eberlein, C.V. 78, 79, 200
 Eckes, P. 97
 Edelman, M. 77, 251
 Ehlke, N.J. 200, 201, 263
 Eilers, R.J. 196, 258
 Ellis, J.R. 329
 Engelke, M.C. 246
 Erickson, D.A. 69
 Etienne, A.L. 19, 284
 Evers, G.W. 314
 Evron, Y. 255
 Eycken, F. van 315
 Ezhova, T.A. 17
 Fabacher, A.P. 313
 Fay, P.K. 104, 259
 Fedtke, C. 60, 302
 Fehr, W.R. 156
 Felipe, M.R. de 118
 Feri, R.J. 298
 Ferrario, S. 157
 Ferrell, M.A. 135
 Fery, R.L. 72
 Figeys, H. 238
 Fisher, J.A. 256
 Fonne-Pfister, R. 162
 Fraley, R.T. 171
 Frear, D.S. 180, 208
 Freytag, A.H. 286
 Friesen, L.F. 277
 Fromm, M.E. 152, 261
 Fuerst, E.P. 78, 106
 Fuks, B. 238, 315
 Gaal, I. 210
 Galili, S. 99
 Gallitano, L.B. 160
 Gallois, P. 120
 Galun, E. 99
 Garcia-Baudin, J.M. 337
 Gaubier, P. 227
 Geiges, B. 110
 Gengenbach, B.G. 13
 Gerwick, B.C. 258
 Ghersa, C.M. 47
 Gianfranceschi, L. 157
 Giaquinta, R.T. 183
 Gillespie, G.R. 280
 Gjerstad, D.H. 4
 Gleddie, S. 248
 Glover, G.R. 4
 Goldburg, R.J. 100
 Goldsbrough, P.B. 109, 290
 Gondet, L. 28, 126
 Goodall, J.S. 107
 Gorla, M.S. 157
 Gossett, B.J. 271
 Gostimskii, S.A. 17
 Graham, J. 161
 Grant, W.F. 68
 Gray, J.A. 39
 Green, J.M. 279
 Green, T.H. 4
 Gressel, J. 7, 8, 70, 130, 179, 190, 223, 255
 Grichar, W.J. 314
 Gronwald, J.W. 13, 23, 91, 200, 201
 Grooms, L. 128
 Gu, W. 112
 Guenzi, A.C. 136
 Guerche, P. 37
 Gullner, G. 225
 Gunsolus, J.L. 140
 Gupta, A.S. 177
 Guttieri, M.J. 78, 79
 Haase, E. 121
 Hagood, E.S. 332
 Hails, R.S. 81
 Haissig, B.E. 247
 Hall, J.C. 50, 71, 103, 146, 193
 Hall, L.M. 41, 188
 Hamill, A.S. 139, 278
 Hanioka, Y. 236
 Harker, K.N. 105
 Harms, C.T. 144
 Harrison, H.F. Jr 63, 72
 Hart, J.J. 184
 Hart, S.E. 42, 288
 Harvey, R.G. 306, 326, 327
 Hasegawa, P.M. 290, 324
 Hattori, J. 218
 Hatzios, K.K. 26, 46, 283, 332
 Haughn, G.W. 214
 Hausler, R.E. 57, 58
 Hayashimoto, A. 303
 Hayenga, M. 82
 He, G. 174
 Heering, D.C. 136
 Heim, D.R. 202
 Heimer, Y.M. 165, 233
 Heinen, J.L. 177
 Hepburn, A.G. 131, 301
 Hertig, C. 300
 Hess, F.D. 245
 Hickok, L.G. 187
 Hideg, E. 59
 Higgins, T.J.V. 318
 Hildebrand, O.B. 16
 Hillemann, D. 170, 189
 Hilp, U. 302
 Hinkley, R.B. 256, 317
 Hirschberg, J. 215
 Hodges, T.K. 335
 Hoffer, B.L. 84
 Hoffman, D.L. 79
 Holaday, A.S. 177
 Hollander-Czytko, H. 132
 Holt, J.S. 172, 203, 245
 Holtum, J.A. 274
 Holtum, J.A.M. 16, 18, 56, 57, 58, 176, 203, 229, 273, 275
 Homble, F. 238
 Horne, D.M. 101, 190
 Howard, J. 141
 Hruby, F. 135
 Hubbard, J. 231
 Hussey, P.J. 329
 Iglesias, V.A. 323
 Ikenaga, H. 118
 Inaba, H. 59
 Ingram, D.S. 137
 Islam, A.K.M.R. 24
 Iwata, M. 27
 Jablonkai, I. 283
 Jackson, M.B. 94
 Jacobs, J.M. 239
 Jacobs, N.J. 239
 James, C.S. 90
 James, J. 202
 James, S.W. 123, 220
 Jamieson, D. 43
 Jansen, M.A.K. 70, 77, 251
 Janssens, J. 25
 Jeffery, L.S. 281
 Jen, G.C. 144
 Jodari, F. 313
 John, M.E. 122
 Johnson, B.J. 115, 253
 Jones, J.D. 109
 Jones, M.G.K. 120
 Jordan, M.C. 319
 Jorrin, J. 224
 Jun, C.J. 53
 Kaaria, S. 82
 Kaeppler, H.F. 112
 Kamiyama, K. 236
 Keller, W. 248
 Kennedy, J.M. 281
 Kerby N.W. 252
 Kerby, N.W. 222
 Kerlan, M.C. 191
 Kibite, S. 105
 Kilen, T.C. 174
 Kim, S. 46
 King, J. 87, 145
 Kinoshita, T. 293
 Kiraly, L. 225
 Kirilovsky, D. 19, 284
 Kirkwood, R.C. 64, 65
 Kishore, G.M. 171, 299
 Kless, H. 251
 Knake, E.L. 308
 Knerr, L.D. 108
 Kobets, N.S. 44
 Koch, D.W. 135
 Kochian, L.V. 91
 Koenig, F. 67
 Kohn, D. 81
 Kolganova, T.V. 44
 Komives, T. 225
 Kononowicz, A.K. 324
 Kostewicz, S.R. 14
 Kreis, M. 120
 Kreuz, K. 162
 Kriz, A.L. 301
 Kropff, M.J. 307
 Kurtz, M.E. 194
 Kusanagi, T. 236
 Labbe, H. 218, 276
 Lalithakumari, D. 66
 Lamport, D. T. A. 181
 Landry, B.S. 257
 Landstein, D. 268
 Lannoye, R. 315
 Lannoye, R.L. 238
 Larrinua, I.M. 202
 Laskay, G. 210
 Lass, L.W. 159
 Last, D.I. 336
 Lavie, B. 155
 Lavrent'ev, A.A. 88
 Lax, F.G. III 124
 Le, H. 68
 Lebaron, H.M. 190
 Leckie, D. 154, 198
 Leemans, J. 25, 320
 Lefebvre, P.A. 123, 220
 Lehoczki, E. 210
 Leimgruber, N.K. 299
 Lemerle, D. 185, 256, 317
 Leroux, G.D. 325
 Leslie, J.F. 289
 Lherminier, J. 93
 Li, Z. 303
 Liebel, R.A. 2
 Lijegren, D.R. 57
 Liljegren, D.R. 56
 Lim, L.W. 299
 Linden, H. 118, 240
 Lindsey, K. 120, 125
 Linscombe, S.D. 313
 Loh, W.H.T. 36
 Loney-Gallant, V. 5
 Lotz, L.A.P. 307
 Loveys, B.R. 176
 Lucas, M. 118
 Lutman, P.J.W. 158
 Lyon, B.R. 98
 MacDonald, H.G. 339
 MacDonald, M.V. 137
 MacIsaac, S.A. 193
 Magha, M.I. 37
 Maillot-Vernier, P. 28, 126, 178
 Malkin, S. 77, 99, 251
 Mallory-Smith, C. 167, 173, 216
 Mallory-Smith, C.A. 69, 79
 Malone, R. 120
 Mansooji, A.M. 274
 Marcum, K.B. 246
 Marles, M.A.S. 71, 146, 188
 Marschner, H. 199
 Marshall, G. 65
 Marshall, L.C. 13
 Martin, R. J. 143
 Martinez-Ferez, I.M. 228
 Masiunas, J.B. 6, 38, 267
 Mason, W.L. 15
 Matorin, D.N. 17
 Matsumoto, H. 239
 Matsunaka, S. 53
 Matthews, J.M. 57, 274
 Mattoo, A.K. 77, 251
 Maxwell, B.D. 341
 Mazur, B. 320
 McBratney, B. 61
 McCarty, L.B. 35
 McElroy, D. 264, 336
 McHughen, A. 40, 319
 McMullan, P.M. 83
 McSheffrey, S.A. 40
 Melekhov, E.I. 88
 Mett, V.L. 44
 Middlesteadt, L.A. 144
 Mikami, T. 293
 Miki, B. 218
 Miki, B.L. 11, 276
 Minogue, P.J. 4
 Miranda, T. 284
 Mireles, L.C. 5, 258
 Misawa, N. 118
 Modi, D.R. 49
 Monaco, T.J. 75, 86
 Montoya, A.L. 144
 Moomaw, R.S. 340
 Morchen, M. 230
 Morgan, M. 96
 Morgunov, A. 154
 Mori, K. 293
 Morishita, D. 167
 Morrison, I.N. 85, 89, 226, 277
 Morthorpe, K.J. 74
 Mortimer, A.M. 211
 Morton, C.A. 306
 Moseley, C. 332
 Moss, S.R. 166
 Motsenbocker, C.E. 75
 Mourad, G. 87
 Mousdale, D.M. 252
 Mullineaux, P.M. 129
 Mullner, H. 97
 Murai, N. 214, 303
 Murakoshi, I. 321
 Murdock, E.C. 271
 Murphy, T.R. 253
 Murr, D.P. 103
 Murray, D. 144
 Murray, G.A. 312
 Myers, M.G. 326, 327
 Nagata, R.T. 298
 Nagel, J. 323
 Nakamura, K. 330
 Nandihalli, U.B. 331
 Nash, C. 22
 Natera, C. 310
 National Agricultural Library (U.S.) 192
 Nazario, S.L. 138
 Negrotto, D.V. 144
 Neumann, K. 189
 Nevo, E. 154, 155
 Newhouse, K. 221
 Newhouse, K.E. 316
 Newsom, L.J. 294, 295
 Nicol, H. 74
 Nishimoto, R.K. 235
 Nojirl, C. 27
 Noll, J. 83
 Norman, M.A. 106
 Nowakowski, M.R. 339
 Oettmeier, W. 302
 Ogg, P.J. 135
 Ooba, S. 27
 Orfanedes, M.S. 2
 Ortel, B. 232
 Osusky, M. 323
 Ow, D.W. 96
 Padgette, S.R. 171, 299
 Pantone, D.J. 338
 Park, S.J. 278
 Parker, B.B. 154
 Parthier, B. 232
 Pautot, V. 9
 Pecker, I. 215
 Peeper, T.F. 136
 Penner, D. 42, 288
 Perewoska, I. 284
 Perl, A. 99
 Perl-Treves, R. 99
 Petrova, T.V. 17
 Piruzyan, E.S. 44
 Pofelis, S. 68
 Pohler, C.L. 314
 Potrykus, I. 164, 323
 Powell, H.A. 222, 252
 Powles, S.B. 16, 18, 24, 33, 56, 57, 58, 176, 186, 203, 229,
 244, 273, 274, 275
 Prado, R. de 224
 Preston, C. 186, 229, 275
 Primiani, M.M. 304
 Przibilla, E. 292
 Puhler, A. 170, 189, 322
 Purba, E. 186
 Putwain, P.D. 211
 Quail, P.H. 27
 Quesenberry, J.E. 96
 Radosevich, S.R. 47, 184
 Rakow, G. 328
 Rao, A.K. 49
 Rashid, A. 277
 Rathinasabapathi, B. 145
 Rathore, K.S. 335
 Ray, C. 96
 Reboud, X. 54
 Rees, M. 81
 Reinbothe, S. 232
 Renard, M. 37
 Renner, K.A. 217
 Rensen, J.J.S. van 30
 Rensen, J.S. van 265
 Reungjitchachawali, M. 165
 Reynaerts, A. 25
 Richter, J. 244
 Ricotta, J.A. 6, 267
 Riemenschnedier, D.E. 247
 Rimmer, S.R. 10
 Rines, H.W. 112
 Romano, M.L. 71, 193
 Rowell, P. 222, 252
 Rubin, B. 76, 166, 195
 Rutledge, R. 218
 Saari, L.L. 153, 260, 304
 Saavedra, M. 310
 Saito, K. 321
 Samarajeewa, P.K. 27
 Sanchez, M. 224
 Sanders, D.E. 313
 Sandmann, G. 110, 118, 240
 Sathasivan, K. 214
 Sathasivan, Kanagasabapathi, 213
 Saumitou-Laprade, P. 230
 Saunders, J.W. 42, 217, 288
 Scalla, R. 92, 93
 Scandalios, J.G. 111
 Schaefer, T.J. 316
 Schaller, H. 28, 126, 178
 Schmidt, A. 240
 Schmidt, R.R. 302
 Schmitzer, P.R. 196
 Schneegurt, M.A. 202
 Schneider, K. 151
 Schonfeld, M. 195
 Schoper, J. 61
 Schotz, A.H. 318
 Schroeder, H.E. 318
 Schubert, A.M. 314
 Scott, J.E. 45
 Secor, G. 208
 Servos, J. 121
 Shafii, B. 73, 285
 Shalgi, E. 99
 Shaner, D. 221
 Shaner, D.L. 205
 Sharkey, T.D. 266
 Shaw, D.R. 149, 294, 295
 Sheets, T.J. 86
 Sherman, T.D. 239
 Shieh, H.S. 299
 Shillito, R.D. 144
 Shimabukuro, R.H. 71, 84
 Shyr, Y.Y.J. 131
 Siangdung, W. 165
 Sikorski, J.A. 299
 Silflow, C.D. 220
 Singh, B. 221
 Singh, B.K. 316
 Singh, D.R. 49
 Singh, H.N. 49
 Singh, N.K. 290
 Sixto, H. 337
 Skroch, W.A. 134, 160, 272
 Smale, B.C. 190
 Smeda, R.J. 80, 106, 142, 226, 241, 290
 Smith, K. 14
 Smith, W.A. 316
 Smith, W.F. 304
 Snape, A. 242
 Snape, J.W. 154, 155, 198, 291
 Snipes, C.E. 80, 142
 Soltanifar, N. 164
 Somers, D.A. 13, 20, 112, 201, 263
 Sommer, I. 132
 Spangenberg, G. 323
 Spencer, D. 318
 Srivastava, V. 261
 Stalker, D.M. 62
 Stall, W.M. 14, 305
 Stallings, W.C. 299
 Starrett, M.A. 316
 Staub, J.E. 108
 Stegeman, R.A. 299
 Stemler, A. 184
 Stewart, J.M. 122
 Stidham, M. 221
 Stidham, M.A. 168
 Stoltenberg, D.E. 39, 270
 Street, J.E. 296
 Stritzke, J.F. 12
 Stroom, P. 220
 Subramanian, M.V. 5
 Suh, H. 301
 Sundby, C. 95
 Sunohara, G. 218
 Swain, R.S. 209
 Swanson, H.R. 180, 208
 Swensen, J.B. 312
 Szigeti, Z. 210
 Takamatsu, S. 27
 Takamizo, T. 323
 Tal, A. 76
 Tamazaki, M. 321
 Tanticharoen, M. 165
 Tardif, F.J. 325
 Thalacker, F.W. 180
 Therrien, M.C. 83
 Thill, D. 167
 Thill, D.C. 69, 73, 79, 173, 216, 285, 312
 Thompson, L.C. 82
 Thompson-Taylor, H. 144
 Thomson, L.W. 71
 Thornhill, R. 219
 Tikhvinskaya, N.S. 17
 Till-Bottraud, I. 54
 Toki, S. 27
 Toler, J.E. 271
 Tomes, D.T. 324
 Tonnemaker, K.A. 69
 Torres, A.C. 298
 Trolinder, N. 96
 Trunkle, P.A. 104
 Tucker, E.S. 33
 Uchimiya, H. 27
 Ulf-Hansen, P.F. 211
 Ulrich, J.F. 279
 Ulrich, T. 32
 United States-Israel Binational Agricultural Research and
 Development
 Fund 181
 University of Maryland at College Park, Dept. of Botany 182
 Urmeeva, F.I. 44
 Van Dijk, H. 230
 Van Doorne, L.E. 65
 Van Eycken, F. 238
 Van Roggen, P.M. 64
 Vasil'ev, I.R. 17
 Vasil, I.K. 152, 261, 297
 Vasil, V. 152, 261
 Vaucheret, H. 9
 Vaughn, K.C. 29, 106, 226
 Vega, D. 227
 Vermeulen, A. 9
 Vernet, P. 230
 Vernotte, C. 117
 Villa, M. 157
 Vioque, A. 228
 Vitolo, D.B. 280
 Vos, O.J. de 30
 Waldin, T.R. 329
 Wall, D.A. 114
 Walls, F.R. Jr 175
 Walter, C. 170, 189
 Wang, Y. 109
 Wang, Z.Y. 323
 Wardley-Richardson, T. 318
 Warnes, D.D. 20
 Warren, S.L. 160
 Warwick, S.I. 148
 Waters, S. 133
 Wax, L.M. 2
 Webb, J. 248
 Weill, S.W. 194
 Weimer, M.R. 3
 Welacky, T.W. 139
 Weller, S.C. 109, 241, 290
 Weston, L.A. 45, 108
 Weymann, K. 144
 Whitwell, T. 52, 231
 Widholm, J.M. 131, 250, 301
 Wiederholt, R.J. 270
 Williamson, D.R. 107, 339
 Wilmink, A. 287
 Windhovel, U. 110
 Witrzens, B. 336
 Woolhouse, H.W. 249
 Worsham, A.D. 175
 Wrather, J.A. 286
 Wu, R. 264
 Wyse, D.L. 13, 91, 119, 200, 201, 263
 Xu, J.R. 289
 Yamamoto, R. 292
 Yamano, S. 118
 Yamasue, Y. 236
 Yan, K. 289
 Yoneyama, K. 321
 Young, R.R. 74
 Yu, C.Y. 38
 Zehr, U.B. 324
 Zhu, D. 111
 Zilkey, B.F. 276
 
                          SUBJECT INDEX
 
 2,4-d 29, 35, 88, 96, 98, 311, 314, 326, 327
 2,4-db 74
 Abiotic injuries 72, 76, 231, 235, 314, 342
 Abscisic acid 88
 Absorption 2, 3, 4, 6, 26, 38, 42, 46, 86, 175, 193, 332, 333
 Abutilon theophrasti 3, 23, 39, 239, 258
 Acc 103
 Acer pseudoplatanus 269
 Acer rubrum 4
 Acetochlor 224, 283, 326, 327
 Acetoin 258
 Acetyl coenzyme a 270
 Acetyl-coa carboxylase 13, 71, 134, 146, 193, 200, 201, 244
 Acifluorfen 6, 14, 38, 239, 267
 Acyltransferases 27, 152, 164, 170, 191, 261, 318, 320, 323,
 335
 Adaptation 66
 Additives 280
 Adenosinetriphosphatase 41, 90
 Africa 31
 Age of trees 235
 Agricultural research 7
 Agriculture 7
 Agrobacterium 276
 Agrobacterium rhizogenes 62, 321
 Agrobacterium tumefaciens 9, 40, 62, 96, 242, 247, 318, 319,
 320, 322
 Agronomic characteristics 11, 122
 Agrostis stolonifera var. palustris 202
 Alachlor 224, 326, 327
 Alberta 105, 188
 Alcaligenes 96, 98
 Alcohol oxidoreductases 232
 Algae 165, 233
 Alkyl (aryl) transferases 232, 252, 301
 Alleles 13, 87, 123, 124, 174, 218, 220, 221, 230
 Allelism 13, 316
 Alloenzymes 155
 Alnus glutinosa 107
 Alopecurus myosuroides 211
 Alpha-amylase 83
 Alpha-glucosidase 83
 Alternaria brassicicola 137
 Amaranthus cruentus 224
 Amaranthus hybridus 224, 327
 Amaranthus lividus 254
 Amaranthus palmeri 271
 Amaranthus powellii 78, 309
 Amaranthus retroflexus 239, 258, 302
 Amaranthus spinosus 254
 Ametryn 16
 Amidase 53
 Amines 326
 Amino acid metabolism 129, 136, 232
 Amino acid sequences 78, 79, 109, 121, 129, 215, 218, 227,
 228, 268, 284, 300
 Amino acids 29, 145, 232, 299
 Amiprofos-methyl 123, 124, 220, 226
 Amitrole 16
 Ammonia 49
 Amplification 109, 129, 131, 144, 232, 301
 Anabaena variabilis 222, 252
 Anilide herbicides 268
 Anions 265
 Annual habit 230
 Antagonism 162
 Antibiotics 287
 Antioxidants 225
 Apocynum cannabinum 2
 Application 72
 Application date 75, 254, 326, 327
 Application methods 89, 140
 Application rates 14, 45, 50, 75, 76, 89, 114, 136, 231, 246,
 254, 271, 276, 278, 280, 296, 305, 311, 313, 326, 327, 338
 Applications 141
 Arabidopsis thaliana 9, 40, 41, 87, 120, 202, 214, 218, 248,
 300, 303
 Arctotheca calendula 186, 275
 Aromatic acids 299
 Aromatic compounds 121
 Artificial selection 17
 Aryloxyphenoxypropionic herbicides 146
 Ascorbic acid 6
 Assays 258
 Asulam 35
 Atp 90, 121, 134
 Atrazine 16, 17, 22, 23, 35, 39, 54, 78, 224, 238, 286, 290,
 302, 326, 327
 Atropa belladonna 321
 Australia 18, 57, 58, 84, 105, 274, 275
 Avena fatua 71, 83, 105, 179, 193, 274
 Avena sativa 104, 105, 112, 179, 340
 Avena sterilis subsp. ludoviciana 274
 Backcrossing 298
 Barban 226
 Benomyl 289
 Bentazone 35, 72, 224, 314, 326, 327
 Benzoic acid herbicides 87
 Beta vulgaris 42, 120, 217, 230, 288
 Beta vulgaris var. saccharifera 230, 320
 Beta-glucuronidase 112, 261, 324, 335
 Betula pendula 107
 Bibliographies 151
 Bidens pilosa 235
 Bilanafos 25, 320, 321
 Binding proteins 284
 Binding site 5, 77, 78, 87, 121, 145, 202, 255, 265, 268, 309
 Bioassays 45, 254
 Biochemical pathways 29, 56, 129, 178, 240
 Biodegradation 251
 Biological control 7
 Biological development 67
 Biosynthesis 29, 45, 93, 103, 110, 118, 145, 178, 233, 239,
 240, 299
 Biotechnology 7, 8, 10, 32, 47, 48, 63, 101, 119, 122, 141,
 156, 171, 179, 183, 245, 262, 308, 334
 Biotypes 14, 16, 18, 23, 29, 33, 39, 56, 57, 58, 59, 73, 77,
 78, 79, 85, 89, 90, 94, 103, 106, 142, 146, 167, 172, 176,
 186, 188, 193, 200, 201, 207, 210, 216, 225, 226, 229, 230,
 236, 238, 243, 258, 260, 266, 270, 271, 273, 274, 275, 277,
 280, 285, 304, 309, 315, 325
 Bipolaris 66
 Bitypes 244
 Blight 27
 Brassica 191
 Brassica campestris 10, 114, 317
 Brassica carinata 10
 Brassica hirta 239
 Brassica juncea 10
 Brassica napus 10, 37, 69, 85, 89, 95, 114, 137, 158, 184,
 191, 243, 248, 266, 317, 328
 Brassica napus var. oleifera 81
 Brassica nigra 191
 Brassica oleracea 45, 191
 Brassica oleracea var. capitata 191
 Brassinolide 150
 Breeding methods 328
 Breeding programs 249
 Bromacil 309
 Bromoxynil 55, 74, 138, 234, 326, 338
 Buchloe dactyloides 35, 246
 Cabt 39, 50, 70, 75, 85, 89, 114, 149, 175, 194, 230, 235,
 270, 277, 278, 280, 280, 280, 280, 280, 280, 285, 296, 311,
 314, 326, 327, 338, 340
 Calamagrostis 231
 Callus 17, 64, 68, 112, 126, 136, 152, 170, 178, 261, 286,
 297, 323, 336
 Canada 114, 276
 Carbamate herbicides 227
 Carbohydrate metabolism 202
 Carbon 60, 265
 Carica papaya 235
 Carotenoids 110, 118
 Cassia obtusifolia 239
 Catalase 237
 Cauliflower mosaic caulimovirus 321
 Cell culture 36, 132, 217, 241, 291, 293
 Cell cultures 3, 92, 93, 145, 237, 250
 Cell differentiation 250
 Cell division 124
 Cell lines 109, 233, 301
 Cell membranes 58
 Cell suspensions 3, 92, 93, 131, 144, 170, 264, 297, 323
 Cell ultrastructure 93
 Cell wall components 93, 202
 Cell walls 29, 93, 207
 Cells 290
 Cellulose 93, 202
 Centaurea repens 159
 Ceratopteris 187
 Characterization 3, 180
 Chelates 14
 Chemical composition 237, 283, 329
 Chemical control 14, 35, 50, 85, 89, 114, 115, 153, 171, 172,
 175, 235, 263, 271, 280, 311, 314, 325, 326, 327, 332, 342
 Chenopodium album 239, 258, 302, 315, 326
 Chenopodium rubrum 237
 Chimerism 129
 Chlamydomonas reinhardtii 123, 124, 220, 292, 302, 330
 Chloramben 108
 Chlorella 268
 Chlorimuron 42, 196, 279, 288, 294, 295, 331, 332
 Chlorophyll 6, 45, 195, 199, 210, 224, 237, 266, 315
 Chloroplast genetics 78, 230, 243
 Chloroplasts 177, 224, 230, 257, 330
 Chlorotoluron 16, 155, 291, 337
 Chlorpropham 226
 Chlorpyrifos 305
 Chlorsulfuron 5, 9, 11, 18, 37, 40, 41, 42, 56, 69, 79, 87,
 116, 120, 137, 180, 185, 188, 217, 218, 248, 256, 260, 273,
 277, 303, 304
 Chlorthal-dimethyl 226
 Chromosome pairing 191
 Cichorium intybus 9
 Cirsium arvense 263
 Clomazone 3, 45
 Clones 43, 75
 Cloning 21, 44, 215, 240, 300
 Clopyralid 2
 Collections 108
 Competitive ability 73, 285
 Complementation 111, 123
 Conazole fungicides 28
 Conservation tillage 1
 Conyza bonariensis 70, 106, 275
 Conyza canadensis 210, 236
 Copper 99
 Coreopsis 342
 Cortaderia 231
 Corydalis 132
 Crop damage 11, 26, 72, 74, 75, 76, 108, 115, 185, 246, 256,
 278, 294, 295, 306, 311, 314, 332, 338
 Crop density 114, 340
 Crop growth stage 243, 338
 Crop management 122, 307
 Crop production 82, 102
 Crop rotation 282
 Crop weed competition 73
 Crop yield 10, 11, 75, 114, 254, 295, 296, 313, 328, 338, 340,
 341
 
 Crops 8, 47, 62, 63, 98, 100, 119, 125, 129, 130, 133, 141,
 149, 161, 163, 171, 183, 197, 203, 245, 249, 262, 308
 Cross resistance 16, 33, 38, 42, 56, 58, 85, 87, 145, 172,
 188, 196, 224, 226, 260, 271, 273, 274, 277, 309, 329
 Crosses 247
 Crossing 184, 221
 Cucumis sativus 108, 239, 281
 Cultivars 8, 10, 46, 48, 50, 60, 63, 65, 69, 72, 75, 88, 114,
 134, 139, 185, 208, 230, 247, 256, 278, 281, 283, 294, 295,
 305, 317, 324, 328, 332, 337, 338
 Culture media 65, 217
 Cuticle 6, 267
 Cyanazine 16, 224, 326, 327
 Cyanobacteria 19, 117, 228, 240, 284
 Cyclohexene oxime herbicides 146, 200
 Cycloxydim 274
 Cynodon 115
 Cynodon dactylon 115, 253
 Cyperus esculentus 342
 Cyperus rotundus 253
 Cytochrome p-450 162, 180
 Cytochromes 251
 Cytogenetics 191
 Cytoplasm 126
 Cytoplasmic male sterility 230
 Dalapon 85, 242
 Dark 59, 337
 Datura fastuosa 145
 Datura stramonium 239
 Daucus carota 131, 301, 322
 Deamination 60
 Defense mechanisms 249
 Degradation 199, 242
 Density 267
 Deposition 46
 Detection 172, 238, 258
 Detoxification 70, 129, 245
 Deuterium oxide 123
 Development plans 119
 Diagnostic techniques 329
 Dicamba 35, 326, 327
 Dichlobenil 93
 Diclofop 35, 51, 57, 58, 71, 83, 84, 85, 105, 180, 193, 200,
 201, 207, 244, 260, 273, 274
 Difenzoquat 154, 198
 Diflufenican 65
 Digitaria sanguinalis 270
 Dinitroaniline herbicides 29, 85, 226, 329
 Dinoseb 17
 Diquat 14, 33, 38, 186, 229
 Direct
 DNAuptake 62, 112, 120, 152, 164, 303, 323, 335
 Disease resistance 10, 22, 27, 36, 137, 139
 Dispersal 341
 Distribution 128
 Diurnal variation 243
 Diuron 16, 17, 74, 77, 78, 238
 Diversity 174
 Dna 49, 99, 230, 264
 Dna amplification 257
 Dna hybridization 21
 Dominance 37, 126, 186, 217, 230
 Drift 296
 Droplets 126
 Drought 340
 Drug resistance 120, 164, 323
 Dry matter 54
 Dry matter accumulation 33, 184, 304
 Duration 337
 Echinacea purpurea 342
 Eclipta alba 342
 Ecology 81
 Economic impact 82, 245
 Economic thresholds 341
 Economic viability 102
 Ecotypes 155
 Edifenphos 66
 Efficacy 326, 342
 Egypt 70
 Eicosapentaenoic acid 165, 233
 Electrical activity 71
 Electron transfer 77, 251, 265, 284, 290
 Electrophoresis 21
 Electrophysiology 207
 Electroporation 120, 297
 Eleusine indica 329
 Elymus repens 280, 325
 Embryogenesis 152, 261, 323
 Emission 59
 England 107, 269, 339
 Environmental factors 295
 Environmental impact 82, 100, 138
 Environmental protection 245
 Enzyme activity 13, 23, 26, 40, 41, 42, 53, 68, 70, 87, 90,
 96, 99, 103, 106, 111, 129, 132, 134, 144, 146, 162, 164, 170,
 180, 193, 200, 201, 218, 221, 232, 237, 252, 259, 260, 263,
 268, 273, 283, 288, 304, 316, 321, 322, 324, 336
 Enzyme inhibitors 5, 29, 42, 136, 168, 188, 205, 240, 258,
 270, 288
 
 Enzyme polymorphism 155
 Enzymes 41, 70, 98, 103, 106, 215, 228, 242, 259
 Epilobium 22
 Epinasty 94, 103
 Eptc 85
 Eragrostis 231
 Erianthus 134, 231, 272
 Erigeron sumatrensis 236
 Erwinia uredovora 110
 Erysiphe cichoracearum 22
 Escherichia coli 44, 299
 Establishment 339
 Ethalfluralin 85, 281
 Ethanol production 210
 Ethics 47, 102
 Ethylene production 94, 103
 Euglena gracilis 232
 Evolution 154, 230, 300
 Excretion 49
 Exons 300
 Explants 318
 Fagopyrum tataricum 239
 Farm woodlands 269, 339
 Fatty acids 165
 Fecundity 285
 Fenoxaprop 71, 83, 85, 231, 272, 274
 Fertility 112
 Festuca 134, 272
 Festuca arundinacea 323, 333
 Festuca ovina 134, 272
 Festuca rubra 333
 Fiber quality 122
 Field experimentation 107
 Field tests 55, 169, 194, 197, 234, 253, 296, 334
 Flagella 123, 124
 Florida 212, 254, 298
 Fluazifop 33, 58, 85, 134, 274
 Fluazifop-p 231, 272
 Fluometuron 16
 Fluorescence 195, 210, 266, 315, 337
 Fluridone 240
 Fluroxypyr 2, 158
 Flurtamone 114, 240
 Fodder legumes 314
 Foliar application 175, 236
 Foliar uptake 6
 Food crops 31, 32
 Food processing quality 32
 Food quality 32
 Food safety 100
 Food supply 31
 Forest nurseries 15, 107
 Forest trees 43, 100
 Formic acid 265
 France 230
 Fraxinus excelsior 269
 Free amino acids 259
 Free radicals 111, 199
 Fruit trees 311
 Fungicide tolerance 28
 Gaillardia 342
 Gas production 210, 229
 Gene dosage 131
 Gene expression 11, 21, 44, 99, 109, 110, 111, 121, 129, 131,
 132, 170, 177, 244, 264, 276, 287, 336
 Gene flow 148
 Gene frequency 155
 Gene interaction 123, 124
 Gene location 174
 Gene mapping 117, 220, 249, 264
 Gene splicing 298
 Gene transfer 9, 21, 40, 49, 62, 96, 97, 99, 111, 120, 152,
 164, 171, 179, 198, 214, 242, 245, 248, 264, 297, 318, 319,
 320, 321, 323, 324, 335, 336
 Genes 8, 78, 79, 96, 98, 109, 120, 122, 129, 154, 186, 215,
 217, 218, 228, 232, 236, 240, 290, 305, 316, 320, 330
 Genetic analysis 21, 44, 78, 257, 276
 Genetic change 123
 Genetic code 44, 177, 257, 322
 Genetic engineering 8, 20, 31, 32, 34, 44, 55, 63, 81, 97, 98,
 113, 122, 125, 127, 128, 129, 130, 138, 161, 163, 189, 212,
 249, 250, 292
 Genetic improvement 10, 249
 Genetic markers 155, 179, 318
 Genetic polymorphism 154
 Genetic regulation 132, 170, 174, 233, 289
 Genetic resistance 8, 11, 20, 23, 32, 125, 157, 223
 Genetic resources 154, 155
 Genetic transformation 9, 25, 27, 40, 49, 62, 96, 98, 99, 110,
 111, 112, 120, 125, 129, 144, 152, 164, 170, 214, 218, 242,
 247, 261, 264, 276, 287, 297, 303, 318, 319, 320, 321, 323,
 324, 335
 Genetic variation 11, 43, 57, 75, 79, 94, 145, 148, 214, 237,
 283
 Genetics 192
 Genome analysis 10, 21
 Genotypes 6, 63, 65, 69, 83, 105, 155, 187, 198, 230, 262,
 267, 276, 283, 324
 Geographical distribution 78, 154, 155
 Georgia 253
 Germplasm 12, 72, 105, 108, 173, 174
 Gibberella fujikuroi 289
 Gibberellins 150
 Gloeocapsa 49
 Glucose 93
 Glufosinate 29, 97, 112, 152, 164, 170, 179, 191, 261, 264,
 318, 319, 320, 321, 322, 323, 335
 Glutathione 283
 Glutathione reductase (nad(p)h) 106
 Glutathione transferase 23, 26, 129, 283
 Glycine max 3, 46, 60, 92, 93, 139, 174, 286, 294, 295, 296,
 331, 332, 333
 Glycoproteins 300
 Glyphosate 4, 17, 27, 29, 33, 44, 64, 65, 109, 131, 132, 133,
 171, 187, 222, 232, 247, 252, 263, 298, 299, 301, 311, 319,
 325
 Gossypium 55, 80, 122
 Gossypium hirsutum 5, 96, 234
 Gramineae 159
 Grasses 52, 135, 231
 Great Britain 15
 Greenhouse culture 184
 Ground cover plants 339
 Groundwater pollution 100
 Growth 40, 64, 165, 184, 237, 250
 Growth chambers 88, 184
 Growth effects 194
 Growth inhibitors 64
 Growth models 307
 Growth rate 33, 73, 136, 306, 332, 333
 Growth regulators 103
 Growth stages 70
 Guanidines 44
 Haloxyfop 13, 200, 244, 274, 333
 Haploids 137
 Hawaii 235
 Heat 170
 Heat stress 315
 Heat tolerance 315
 Heavy metals 36
 Herbicidal properties 168, 207, 210, 239, 240, 265, 273
 Herbicide mixtures 14, 160, 162, 269, 305, 327, 342
 Herbicide residues 60, 269, 339
 Herbicide resistance 1, 2, 3, 5, 6, 7, 8, 9, 10, 11, 12, 13,
 14, 15, 16, 17, 18, 19, 20, 22, 23, 24, 25, 26, 27, 28, 29,
 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44,
 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 59, 60, 61,
 62, 63, 65, 66, 67, 68, 69, 70, 72, 74, 75, 76, 77, 78, 79,
 80, 82, 83, 84, 85, 86, 87, 88, 89, 90, 92, 93, 94, 95, 96,
 97, 98, 99, 100, 101, 102, 103, 104, 105, 106, 107, 108, 109,
 110, 111, 112, 113, 114, 115, 116, 117, 118, 119, 120, 121,
 123, 124, 125, 126, 127, 128, 129, 130, 131, 132, 133, 134,
 135, 136, 137, 138, 139, 141, 144, 145, 146, 147, 148, 149,
 150, 151, 152, 154, 155, 160, 161, 162, 163, 164, 165, 168,
 169, 170, 171, 172, 173, 174, 175, 176, 177, 178, 179, 180,
 183, 184, 185, 186, 187, 188, 189, 191, 193, 194, 195, 197,
 198, 199, 200, 201, 202, 203, 204, 205, 206, 207, 208, 209,
 210, 211, 212, 214, 215, 216, 217, 218, 220, 221, 222, 223,
 224, 225, 226, 227, 228, 229, 231, 232, 233, 234, 235, 236,
 237, 238, 239, 240, 241, 242, 243, 244, 245, 246, 247, 248,
 249, 250, 251, 252, 253, 254, 255, 256, 257, 258, 259, 260,
 261, 262, 263, 264, 265, 266, 267, 268, 269, 270, 271, 272,
 274, 276, 277, 278, 279, 280, 281, 282, 283, 284, 285, 286,
 287, 288, 289, 290, 291, 292, 293, 294, 295, 296, 297, 298,
 299, 300, 301, 302, 303, 304, 305, 306, 307, 308, 309, 311,
 313, 314, 316, 317, 318, 319, 320, 321, 323, 324, 325, 327,
 328, 329, 330, 331, 332, 333, 335, 337, 338, 339, 340, 341,
 342
 Herbicide resistant weeds 14, 16, 29, 38, 39, 57, 58, 73, 79,
 85, 86, 89, 90, 140, 142, 148, 153, 166, 167, 172, 186, 190,
 196, 200, 201, 203, 210, 216, 219, 226, 229, 236, 238, 244,
 258, 260, 270, 273, 274, 275, 277, 280, 302, 304, 315, 325,
 326, 327, 341
 Herbicide safeners 129
 Herbicide-resistant crops 147
 Herbicides 1, 7, 15, 49, 52, 58, 64, 91, 98, 100, 107, 129,
 130, 140, 142, 149, 156, 157, 159, 166, 167, 194, 196, 205,
 213, 226, 240, 241, 246, 253, 265, 271, 277, 310, 312, 317,
 340
 Heritability 17, 176
 Heterozygosity 288
 Hexazinone 43
 Hibiscus cannabinus 194
 High yielding varieties 233
 Histoenzymology 112
 History 172
 Homozygosity 288
 Hordeum glaucum 24, 76, 229, 275
 Hordeum murinum subsp. leporinum 33, 186, 229, 275
 Hordeum spontaneum 76
 Hordeum vulgare 24, 76, 83, 185, 256
 Hybrid varieties 82, 283
 Hybridization 10, 24, 230, 245
 Hybrids 26, 53, 115, 191, 248, 279, 306
 Hydrolysis 90
 Hydroponics 294
 Hygromycin b 164, 289, 323
 Idaho 73, 78, 216, 285, 309
 Ilex vomitoria 4
 Imazamethabenz 37
 Imazapyr 87, 136, 244, 304
 Imazaquin 35, 115, 144, 175, 196, 221, 253, 258, 294, 295
 Imazethapyr 5, 135, 221, 254, 316
 Imidazoline 213
 Imidazolinone herbicides 5, 28, 29, 42, 145, 168, 214, 218,
 268, 273
 Improvement 122
 In vitro 291
 In vitro selection 13, 17, 36, 68, 120, 131, 136, 144, 241,
 248, 261, 286, 293, 303, 323, 335
 Inbred lines 221, 279
 Incidence 166
 Incubation 337
 Induced mutations 17, 36, 69, 111, 116, 124, 218, 220, 221,
 316
 Induction 337
 Industry 183
 Inheritance 13, 17, 18, 40, 68, 96, 112, 174, 186, 187, 201,
 217, 221, 236, 261, 288, 316, 321, 330
 Inhibition 41, 71, 77, 87, 146, 224, 268, 302, 337
 Inhibitor genes 124
 Inhibitors 77, 255
 Injuries 50, 107, 140, 281, 296, 317
 Insect control 249
 Insecticide resistance 71
 Integrated control 307
 Interactions 162, 202
 Intergeneric hybridization 248
 International organizations 190
 Interspecific hybridization 191
 Introgression 191
 Introns 300
 Iowa 219
 Ipomoea batatas 75
 Ipomoea lacunosa 239, 332
 Iron fertilizers 115
 Isoenzymes 155
 Isolation 120
 Isoleucine 136, 259
 Isomerases 258
 Isopropalin 85
 Isoproturon 16
 Isotope labeling 60
 Isoxaben 92, 93, 202, 342
 Israel 154, 155
 Kalmia latifolia 160
 Kanamycin 9, 120
 Kinases 232
 Kinetics 337
 Kochia scoparia 79, 259, 277
 Laboratory methods 21, 241, 257
 Lactuca sativa 173, 254, 255, 298
 Lactuca serriola 73, 79, 173, 216, 285
 Larix leptolepis 107
 Lawns and turf 35, 115, 253
 Leaf area 307
 Leaves 4, 6, 46, 53, 57, 59, 175, 199, 210, 229, 242, 267,
 336, 337
 
 Legislation 101
 Leucanthemum vulgare 342
 Leucine 5, 136, 259
 Leucothoe walteri 160
 Life cycle 230
 Ligases 5, 40, 44, 56, 87, 109, 132, 145, 168, 205, 258, 263,
 304, 320
 Light 59, 70, 210, 251, 284
 Light intensity 59, 67, 117, 184, 199, 210
 Line differences 40, 54, 92, 93
 Lines 11, 91, 93, 165, 184, 237, 288, 291
 Linkage groups 220
 Linolenic acid 165, 233
 Linum usitatissimum 40, 319
 Linuron 50, 85, 180, 327
 Lipids 126
 Lipogenesis 126
 Literature reviews 7, 8, 10, 29, 36, 62, 98, 125, 166, 171,
 247, 265, 287
 Loci 87, 123, 124, 174
 Lolium multiflorum 51, 200, 201
 Lolium perenne 304
 Lolium rigidum 16, 18, 56, 57, 58, 84, 176, 207, 244, 260, 273
 Lotus corniculatus 68, 263
 Louisiana 234, 338
 Lupinus albus 317
 Lupinus angustifolius 317
 Lyases 188, 196, 299
 Lycopersicon esculentum 6, 14, 82, 94, 99, 208, 267
 Macroeconomics 10
 Magnesium 199
 Maize 157
 Malathion 162
 Malus pumila 311
 Manganese 111
 Manitoba 71, 83, 85, 89, 146, 226, 277
 Marker genes 25, 155, 179, 242, 287, 303, 335, 336
 Maryland 23
 Massachusetts 280
 Maternal effects 201, 230
 Mathematical models 341
 Maturity stage 86
 Mcpa 29, 74, 224
 Mecoprop 35, 90, 94
 Medicago 74
 Medicago sativa 12, 170, 239, 340
 Mediterranean climate 310
 Meiosis 191
 Membrane potential 58, 71, 84, 91, 207
 Membranes 77, 290
 Messenger
 RNA 109, 131, 132, 232
 Metabolic detoxification 3, 26, 38, 45, 56, 86, 92, 106, 148,
 162, 176, 180, 193, 209, 237, 260, 283, 304, 337
 Metabolic inhibitors 45, 85, 93, 176
 Metabolism 2, 3, 6, 38, 42, 46, 56, 57, 86, 146, 162, 175,
 176, 193, 200, 202, 206, 209, 241, 250, 260, 273, 291, 322,
 332
 Metabolites 3, 45, 60, 86, 92, 176, 193, 260, 291
 Metal tolerance 36
 Metazachlor 15, 158
 Methazole 16
 Methionine 330
 Methylation 178
 Metobromuron 278
 Metolachlor 26, 326, 342
 Metoxuron 16, 154, 155
 Metribuzin 16, 19, 60, 75, 78, 115, 139, 174, 208, 284, 302,
 327, 337
 Metsulfuron 35, 37, 40, 64, 65, 69, 216, 279
 Microbial degradation 98, 227
 Micromanipulation 34
 Microsomes 41, 162, 180
 Microtubules 123, 220
 Mildews 22
 Mineral deficiencies 199
 Minnesota 23, 280
 Miscanthus 231
 Mississippi 142, 149, 194, 295, 296
 Mitochondria 111, 330
 Mitochondrial
 DNA 230
 Mitochondrial genetics 230
 Mitosis 29, 85
 Mixed cropping 249
 Mode of action 29, 45, 46, 93, 116, 140, 146, 149, 168, 205,
 240, 241, 255, 258, 291
 Models 166, 215
 Modification 122
 Molecular biology 21, 25, 250
 Molecular genetics 116, 240
 Monitoring 238
 Monocotyledons 287
 Monophenol monooxygenase 180
 Motility 124
 Msma 35, 115
 Multiple genes 117, 144
 Mutagenesis 116, 137
 Mutagens 116, 121
 Mutants 5, 13, 17, 19, 28, 36, 37, 44, 66, 67, 69, 87, 111,
 116, 120, 124, 126, 144, 145, 214, 218, 219, 232, 240, 251,
 268, 284, 292, 302, 303, 316, 330
 Mutations 13, 37, 49, 78, 87, 95, 117, 123, 126, 129, 136,
 144, 187, 215, 228, 243, 284, 290, 303
 Myrothecium verrucaria 127
 Nadh dehydrogenase 180
 Natural selection 148
 Nebraska 1, 340
 Net assimilation rate 266
 New South Wales 74, 185, 256, 317
 New York 280
 Nicotiana 225
 Nicotiana plumbaginifolia 242
 Nicotiana tabacum 5, 11, 28, 44, 59, 96, 98, 109, 118, 120,
 126, 127, 144, 175, 177, 178, 218, 276, 322
 Nitrogen fixation 49
 Nitroso compounds 44
 No-tillage 340
 Nontarget effects 100
 Norflurazon 110, 118, 215, 228, 240
 North Carolina 75, 175
 North Dakota 280
 Nostoc muscorum 49
 Nuclei 330
 Nucleotide sequences 78, 79, 109, 121, 215, 218, 220, 227,
 228, 264, 300, 301, 322
 Nutrient solutions 294
 Ohio 280
 Oilseed plants 10
 Oklahoma 12
 Ontario 50, 139, 278
 Orchards 311
 Oregon 51, 200, 201
 Organ culture 99
 Organic acids 207
 Organic anions 265
 Organophosphorus insecticides 162
 Ornamental herbaceous plants 52, 231
 Ornamental plants 272
 Ornamental woody plants 160
 Oryza 53
 Oryza sativa 27, 66, 164, 264, 293, 296, 303, 313, 335, 336,
 338
 Oryzalin 85, 123, 124, 220
 Oxadiazon 342
 Oxidants 70
 Oxidation 3, 177, 180
 Oxidoreductases 96
 Oxo-acid-lyases 37, 42, 68, 144, 218, 221, 244, 260, 268, 273,
 303, 316
 Oxydendrum arboreum 160
 Oxyfluorfen 14, 38, 235
 Oxygen 99, 111, 176, 199, 210, 229
 Oxygenases 98, 110, 180
 Panicum 231
 Panicum virgatum 134, 272
 Paraquat 14, 24, 29, 33, 38, 46, 59, 70, 99, 106, 111, 186,
 199, 210, 229, 236, 237, 275, 330
 Parasitic weeds 7
 Pathogenicity 66
 Pendimethalin 85, 281, 326, 327
 Pennisetum alopecuroides 134, 272
 Pennsylvania 280
 Perennial weeds 325
 Performance 184
 Peroxidase 237
 Pest management 7, 190, 307
 Pest resistance 10, 20, 125, 128, 190
 Ph 207, 294
 Pharbitis hederacea 332
 Pharmacodynamics 255
 Pharmacokinetics 3, 26, 162, 180, 193, 200, 236, 260, 283, 304
 Phaseolus vulgaris 199, 278
 Phenolic compounds 292
 Phenotypes 49, 124, 155, 201
 Phenoxypropionic herbicides 18
 Phloem loading 41
 Phosphates 44
 Phospholipids 90
 Phosphotransferases 112, 164, 318, 323
 Photoinhibition 30, 70, 95, 177, 275, 284
 Photosynthesis 16, 29, 67, 99, 117, 155, 184, 210, 224, 229,
 238, 243, 250, 255, 265, 266, 290
 Photosystem i 106, 237
 Photosystem ii 19, 30, 49, 77, 95, 117, 251, 255, 265, 284,
 290, 302, 337
 Phototoxicity 99, 140
 Physiological races 193
 Phytoene 110, 240
 Phytophthora megasperma 139
 Phytosterols 126
 Phytotoxicity 3, 5, 11, 26, 53, 56, 68, 72, 74, 75, 76, 84,
 85, 89, 92, 93, 94, 107, 108, 160, 162, 175, 180, 185, 193,
 194, 199, 210, 222, 224, 231, 235, 239, 242, 256, 272, 278,
 279, 283, 286, 294, 295, 305, 306, 310, 311, 314, 317, 330,
 332, 333, 342
 Picea sitchensis 107
 Picloram 103
 Pinus taeda 4
 Pisum sativum 17, 64, 65, 88, 207, 317, 318
 Plant breeding 8, 20, 25, 32, 105, 137, 157, 173, 174, 214,
 223, 233, 248, 249, 257, 279, 286, 298
 Plant cell walls 181
 Plant competition 54
 Plant composition 258, 283
 Plant density 50, 54, 307
 Plant development 32, 125
 Plant ecology 148, 155
 Plant embryos 261, 318
 Plant genetic engineering 192
 Plant height 54, 235
 Plant interaction 307
 Plant morphology 53, 248
 Plant oils 10
 Plant pathogenic fungi 66, 137, 289
 Plant physiology 203, 299, 315
 Plant protection 129
 Plant proteins 67, 121, 232, 251, 265
 Plant regulators 150
 Plant tissues 46
 Plant viruses 249
 Plants 25, 36, 88, 189, 215, 250, 334
 Plants, Effect of herbicides on 182, 213
 Plasma membranes 41, 71, 90, 93, 207
 Plasmalemma 84
 Plasmid vectors 261
 Plasmids 44, 62, 120, 152, 227, 242, 264, 297
 Plastids 232
 Pleiotropy 243
 Poa annua 50, 315
 Poa pratensis 50, 312
 Polarity 58
 Policy 100
 Pollen 116, 244
 Pollen germination 244
 Pollination 230
 Polyethylene glycol 164
 Polymerase chain reaction 257
 Polymorphism 155
 Polyploidy 198
 Population dynamics 216, 341
 Populus alba 247
 Populus grandidentata 247
 Porphyrins 239
 Pot experimentation 107
 Private sector 100
 Prodiamine 85
 Production costs 82
 Profitability 48
 Prometryn 16
 Promoters 110, 336
 Propachlor 224
 Propanil 53, 85
 Propaquizafop 274
 Propazine 16
 Propham 226
 Propyzamide 85, 226, 314
 Protein composition 329
 Protein content 10, 41, 139, 329
 Protein degradation 77
 Protein synthesis 67, 129
 Protein synthesis inhibitors 168
 Proteins 77, 117, 290
 Proton pump 90
 Protoplast fusion 248
 Protoplasts 120, 144, 164, 297, 303, 323, 335
 Provenance 280
 Prunus avium 269
 Prunus dulcis 310
 Prunus persica 311
 Pseudomonas cepacia 227
 Pseudomonas putida 242
 Public agencies 101
 Public health 100
 Public opinion 163
 Public sector 100
 Purification 252
 Pyridate 14, 158, 224, 255, 326, 327
 Pyridine herbicides 85
 Quality 50
 Quantitative techniques 337
 Quercus rubra 4
 Quinclorac 35, 296
 Quinolines 121
 Quinones 265, 284, 290
 Quizalofop 200, 272, 274, 325
 Radioactive tracers 331, 333
 Rain 185
 Raphanus raphanistrum 191
 Rapid methods 257
 Recessive genes 123, 279
 Recombinant
 DNA 110, 318
 Recurrent selection 263
 Redox potential 284
 Regeneration 68, 109
 Regenerative ability 112, 152, 164, 170, 286, 318, 319, 323
 Regulation 70, 101, 266
 Relationships 22
 Repetitive
 DNA 301
 Reporter genes 25, 112, 152, 191, 261, 318, 323, 335
 Research 48, 171
 Resistance 64, 121, 275, 287, 289, 293, 330
 Resistance mechanisms 16, 29, 71, 78, 106, 166, 168, 172, 176,
 200, 205, 226, 304
 Responses 184
 Restriction enzymes, DNA 192
 Restriction fragment length polymorphism 21, 230
 Restriction mapping 21, 117, 215, 301
 Reviews 148, 203, 245
 Rhizoctonia solani 27
 Rhizomes 325
 Rhododendron 160
 Rhododendron catawbiense 160
 Rhododendron obtusum 160
 Rhodophyta 165
 Rice 282
 Risk 102, 262
 Root tips 84
 Root treatment 337
 Roots 4, 40, 45, 99, 175, 207, 283, 331, 333
 Rotations 254, 340
 Saccharomyces cerevisiae 111, 121
 Saccharum 297
 Salsola iberica 79, 304
 Salt tolerance 36, 293
 Saskatchewan 328
 Screening 69, 72, 108, 116, 241, 244, 245, 267, 278, 306, 339
 Seed germination 236, 259, 285
 Seed industry 48
 Seed longevity 285
 Seed set 54
 Seedbeds 107
 Seedling emergence 50
 Seedling stage 86, 175, 278
 Seedlings 17, 180, 276, 281, 283
 Seeds 10, 54, 116, 128, 341
 Segregation 40, 120, 126, 186, 220, 261, 316
 Selection 12, 105, 137, 233, 245, 264, 286, 287, 336
 Selection criteria 24, 116, 122, 184, 263, 276, 290
 Selection pressure 148
 Selective breeding 157, 242
 Selectivity 3, 76, 180, 283
 Semidominance 13, 220, 288
 Semidominant genes 221, 288
 Senecio vulgaris 22
 Serine 95
 Setaria faberi 219, 270
 Setaria italica 54
 Setaria viridis 83, 85, 89, 146, 226, 329, 341
 Sethoxydim 13, 33, 35, 85, 134, 200, 231, 244, 272, 274
 Shade 67
 Shoots 54, 68, 99, 175, 180, 283
 Simazine 16, 176, 327, 342
 Simulation models 307, 341
 Sinapis arvensis 103, 114, 191
 Sisymbrium 74
 Site factors 15, 317
 Site preparation 342
 Soil analysis 254
 Soil ph 91
 Soil temperature 259
 Soil treatment 175
 Soil water content 295
 Solanum 38, 267
 Solanum Americanum 14
 Solanum nigrum 77, 238, 315
 Solanum tuberosum 99, 290
 Somaclonal variation 38, 208, 217, 293
 Somatic embryogenesis 65
 Somatic hybridization 248
 Somatic mutations 217
 Sorghastrum 231
 Sorghum bicolor 258, 324
 Sorghum halepense 80, 142
 Source sink relations 45, 175
 South Carolina 271
 Southeastern states of U.S.A. 4
 Spain 224
 Spartina 231
 Spatial distribution 46, 325
 Species differences 3, 76, 314
 Spectroscopy 238
 Sphaerotheca 22
 Spinacia oleracea 239
 Spirodela oligorhiza 77, 251
 Spirulina 165, 233
 Stable isotopes 325
 Stand establishment 159, 342
 Stellaria media 90, 94, 188, 304
 Stems 4
 Sterol esters 126
 Sterols 90, 178
 Stomata 267
 Strain differences 66, 289
 Strains 49
 Streptomyces 335
 Streptomycin 293
 Stress 99, 111, 177, 284
 Stress response 70
 Structural genes 13, 27, 37, 40, 110, 111, 117, 121, 131, 144,
 152, 170, 220, 243, 244, 284, 300, 301, 335
 Structure activity relationships 129, 168, 302
 Sucrose 41, 325
 Sulfometuron 35, 121, 216, 221, 244, 268, 279, 304
 Sulfonamides 87
 Sulfonylurea herbicides 5, 11, 29, 42, 55, 68, 69, 73, 144,
 145, 162, 168, 173, 188, 209, 216, 259, 273, 276, 279, 280,
 285, 288, 298, 305, 306, 319, 320, 326, 327
 Superoxide dismutase 59, 99, 106, 111, 177, 237
 Supply balance 48
 Surveys 216
 Survival 33, 88, 269, 339
 Susceptibility 2, 22, 41, 46, 60, 84, 89, 91, 92, 93, 103,
 106, 134, 146, 149, 176, 188, 195, 198, 201, 235, 259, 271,
 277, 285, 315, 331, 333, 337
 Sweetcorn 305
 Symptoms 140
 Synechococcus 67, 110, 215
 Systemic action 325
 Systems approach 307
 Technology transfer 308
 Temperate climate 50
 Temperature 70, 124, 185, 266, 337
 Terbacil 12, 86, 309
 Terbucarb 226
 Terbufos 305
 Terbutryn 74
 Texas 246, 314
 Thylakoids 78, 117, 176, 290, 292, 309, 330
 Timing 75, 326, 327
 Tissue culture 17, 36, 64, 68, 131, 241, 318, 324
 Tissue cultures 25
 Tobacco 182
 Tofu 139
 Tolerance 4, 72, 91, 133, 156, 158, 252, 310, 312, 314
 Tomatoes 181
 Trails 142
 Tralkoxydim 76, 274
 Transcription 132
 Transfer 24
 Transferases 131, 321, 322, 324
 Transgenic plants 11, 27, 47, 48, 63, 100, 101, 119, 120, 171,
 183, 191, 261, 262, 303, 308, 318, 319, 335, 336
 Transgenics 9, 21, 40, 44, 62, 81, 96, 98, 99, 112, 118, 144,
 152, 164, 170, 177, 179, 189, 197, 218, 234, 276, 320, 321,
 322, 323, 324
 Translocation 2, 4, 6, 26, 38, 45, 46, 56, 57, 86, 175, 176,
 193, 200, 229, 241, 325, 332, 333, 337
 Treatment 44, 88, 276
 Trees 339
 Triasulfuron 37, 180, 244, 304
 Triazine herbicides 29, 95, 219, 243, 257, 309, 326
 Triazines 15, 148, 184, 266
 Triazole herbicides 5, 126, 178
 Tribenuron 11, 279
 Trichomes 267
 Triclopyr 35, 296, 311, 338
 Tridiphane 14, 326, 327
 Trifluralin 85, 89, 226, 271, 329
 Trifolium alexandrinum 314
 Trifolium hirtum 314
 Trifolium subterraneum 74, 314
 Triticum 198
 Triticum aestivum 24, 34, 56, 73, 76, 85, 89, 92, 93, 113,
 136, 152, 180, 209, 212, 261, 283, 291, 316, 336, 337, 341
 Triticum dicoccoides 154, 155
 Triticum durum 337
 Tubulin 220, 329
 Types 22, 41
 U.S.A. 101, 138, 163, 197, 334
 Uk 22
 Ultrastructure 330
 Ultraviolet radiation 137
 Uptake 45, 46, 57, 146, 176, 202, 241, 325, 331, 332, 333
 Uptake mechanisms 41
 Usda 55, 163, 197, 334
 Uses 141
 Valine 136, 259
 Variation 86
 Varietal resistance 249
 Varietal susceptibility 6, 26, 69, 71, 72, 75, 278, 279, 283,
 291, 294, 295, 305, 306, 332
 Varietal tolerance 338
 Varieties 313
 Variety trials 105
 Vectors 62, 129, 287
 Vegetation management 339
 Vicia faba 317
 Victoria 33
 Vigna unguiculata 72
 Viola arvensis 86
 Virginia 311
 Virulence 66
 Waxes 6, 46, 267
 Weed biology 21, 33, 57, 58, 70, 79, 116, 195, 230, 237, 241,
 280, 341
 Weed competition 307
 Weed control 1, 2, 7, 8, 14, 15, 35, 47, 50, 51, 52, 57, 58,
 74, 82, 83, 85, 89, 95, 97, 100, 114, 115, 119, 130, 133, 134,
 142, 149, 153, 158, 159, 167, 171, 172, 175, 183, 188, 190,
 194, 196, 206, 234, 235, 239, 253, 254, 262, 263, 267, 269,
 271, 277, 280, 298, 307, 308, 311, 314, 317, 325, 326, 327,
 332, 339, 340, 341, 342
 Weeds 1, 2, 7, 21, 116, 148, 176, 195, 204, 230, 241, 269,
 308, 341
 
 Wild plants 53, 71, 76, 154, 174
 Wild strains 302
 Wisconsin 39, 108, 270, 306, 326, 327
 Wyoming 135
 X radiation 248, 299
 Xanthium strumarium 196, 258
 Yield components 10
 Yield losses 75, 95, 295, 307, 317, 341
 Yield response functions 317
 Zea mays 13, 26, 61, 82, 91, 111, 162, 168, 221, 279, 283,
 305, 306, 326, 327, 340
 Zinc 99