ANNUAL  REPORT
Calendar Year 1998

1.  PROJECT: NRSP-6: INTER-REGIONAL POTATO INTRODUCTION PROJECT

Introduction, Preservation, Classification, Distribution and Evaluation of  Solanum Species.

2.  COOPERATIVE AGENCIES AND PRINCIPAL LEADERS

 United States Department of Agriculture

Administrative Advisors

3.  PROGRESS AND PRINCIPAL ACCOMPLISHMENTS

A.  Introduction of New Stocks

Dr. Spooner, in collaboration with Alberto Salas (CIP, Peru), Zozimo Huaman (CIP, Peru), and Robert Hijman (CIP, Peru) participated in a successful expedition to collect wild species of potato in Peru from February18th to April 18^th 1998. This collection trip resulted in 57 new accessions of  Solanum species.

Dr. Bamberg led two trips to the southwest USA to obtain new materials for the collaborative intergenebank project.  As a result, 16 new germplasm accessions from new locations in New Mexico and Arizona were added to the collection.

A total of 97 accessions were assigned PI’s in 1998, and are now available from the NRSP-6 Solanum germplasm collection, 14 in vitro clones, 67 quarantine clones, and 16 accessions from the Southwest United States.

In 1998, 93 new accessions were planted out in the spring quarantined increase. Of the 93 accessions, 64 germinated and were grown out. Sixty-three of these were released and added into the collection (one was virus suspect and not released).  Of the 63 accessions, 42 were from Spooner's 1995 Guatemala collection, 9 were from Spooner's 1996 Costa Rica collection, 7 were from Spooner's 1993 Bolivia collection, and 9 others from various other collection trips.

A total of 33 clones were added to the in vitro collection in 1998 as foreign varieties or genetic stocks.

B.  Preservation and Increase of Stocks

In 1998, 128 accessions were increased. From US Quarantine, 93 accessions were received for a joint seed increase and quarantine virus testing at NRSP-6. Of the 93 accessions, 29 failed to germinate, one was virus suspect and not released, and 55 failed to produce seed in the spring seed increase and are being carried over as cuttings or tubers to be tried again in the 1999 summer seed increase.

This year a total of 678 potato spindle tuber viroid (PSTV) tests were performed on seed increases, seed lots and research materials. Germination tests were performed on 948 accessions, and ploidy determinations were done on 158 accessions.

C.  Classification

Dr. Spooner continues to resolve problems in taxonomic classification which impede efficient documentation and use of the germplasm. This year an extensive study was conducted which suggests several species in the series Longipedicellata are not actually significantly different.  Insights gained from this and similar studies will allow accessions to be assigned stable species names based on empirical differences.

D.  Distribution

NRSP-6 distributed 5,460 units of seed, 46 tuber families and 2,355 in vitro stocks to clientele in 22 states of the United States and 13 other countries.  Internally, NRSP-6 used 9,741 units of seed for chromosome counts, germination tests, identification and taxonomic check plantings, in-vitro maintenance, seed increases, PSTV tests, and miscellaneous plantings.  The volume and types of stocks sent to various consignee categories are summarized in the table below.

VOLUME AND TYPES OF STOCKS DISTRIBUTED

¹Types of stocks sent/(number of seeds, tubers or plantlets per standard shipping
   unit): S= True Seeds/(50), TF= Tuber Families/(10),  IVS=In Vitro Stocks/(1), FSG=Fine
   Screening Genotypes/(1).

²Includes chromosome counts, germination tests, ID and Taxonomic check plantings, in
  vitro maintenance, seed increases, PSTV tests, and miscellaneous plantings and NSSL seed
   backup.

E.  Evaluation of Stocks

Mission

The project's mission with respect to evaluation is to locate and characterize useful traits so that the best materials and most efficient approaches are available for subsequent germplasm enhancement.

1. Late Blight Screening

New forms of the late blight pathogen have developed into a severe threat to the US potato crop.  In 1998 we continued four cooperative projects:

1)      BC, Canada with Dr. Ken Ng: This project characterized segregation for extreme LB resistance in a family of the South American Series Tuberosa member S. okadae.

2)      Cornell, New York: Dr. Fry characterized segregation for extreme LB resistance in a family of the South American Series Tuberosa member S. microdontum.

3)      Lansing, Michigan with Dr. Douches: This project involves inoculated greenhouse testing of selected late blight resistant genotypes.

4)      Toluca, Mexico with Hector Lozoya:  This project did field screening for resistance in various South American and Mexican species, as well as Russian elite breeding families.

2. Tuber Traits

Wild species do not produce tubers in the long days of Sturgeon Bay summers, so their tuber traits cannot be assessed in the field.  A project was initiated in 1993 in which wild accessions are being systematically crossed with adapted (cultivated) forms to produce F2 true seed families. We also found and successfully tested a site for wild species tuber production at Weslaco, TX (in cooperation with TAES).  This will allow more efficient production of tubers and allow evaluation under field conditions (for such traits as calcium accumulation potential).

3. Frost Hardiness

In cooperation with Dr. J. Palta and YuKuang Chen, work was continued on recurrent selection for earliness, good tuber characteristics, and frost resistance.   Progress was made in generation of substitution backcross families with cold sensitive genomes within cold hardy cytoplasm.

4. Tuber Calcium

Tuber calcium has been shown to be closely associated with resistance to important storage rots and other tuber quality traits.  F₂ hybrids between clones which accumulate very high calcium in a high calcium environment and clones which accumulate very little calcium in the same environment were analyzed. High calcium accumulation and cold sprouting vigor were found not to be well correlated.  Tuber calcium segregation within the family was continuous between the parental levels.  These materials should be a valuable tool for investigating the physiology and genetics of tuber calcium.

5.  RAPDs to estimate vulnerability of alleles in the genebank

RAPDs were used to characterize populations of two very heterogeneous wild potato species.  About 25 plants in each population were individually tested to reveal "allele" frequencies.  Allele frequencies less than 25% were not uncommon, but these markers were almost always fixed or nearly fixed in another population.  Therefore, vulnerable alleles (i.e., ones which have a good chance of being lost from the genebank using current seed increase methods) appear to be very rare.

6. Screening the Wild Species for Root Mass

The mini-core collection was screened for root mass in the screenhouse in Perlite. Significant differences were found which parallel those of previous work.  This information may provide insights into breeding for water and fertilizer use efficiency.

7. Characterization for Utility Traits

The success of using Solanum germplasm for breeding is influenced by relative plant vigor, flowering, pollen shed and pollen viability. Characterization of the collection for these traits continued in 1998.

F.  Inter-genebank Collaboration

The Association of Potato Intergenebank Collaborators (APIC) has initiated a joint research project to investigate the effects of seed increases on the genetic integrity of germplasm conserved ex situ, and whether germplasm in genebanks still represents the in situ populations from which they were collected. Work on the final phase, finding factors which predict the patterns of diversity among accessions, nears completion. Some findings defy conventional wisdom, such as the idea that genetic diversity is correlated with spacial separation of collections.  Results from this work will guide collection methods to maximize diversity.   New samples of S. jamesii were collected in New Mexico and Arizona, expanding the range of our research samples and adding unique germplasm to the genebank. The 8th meeting of APIC is planned to be held in conjunction with the Global Potato Conference in New Delhi, December, 1999.  APIC has been invited to present a symposium on international germplasm cooperation.  

 4. USEFULNESS OF FINDINGS

NRSP-6's purpose is to provide a ready source of raw materials, technology and information which support potato enhancement, breeding and research in the US and around the world.  Thus, one way the success of NRSP-6 can be measured is by the use of NRSP-6 germplasm in the pedigrees of new, improved potato cultivars.  Another is in the use of NRSP-6 stocks in more basic research programs which also ultimately contribute to human utilization of the potato crop, these being reflected in publications.

Four cultivar releases were published in the American Journal of Potato Research in 1998: ‘Andover’, ‘NorValley’, ‘OAC Royal Gold’, and ‘Pike’.  All are known to have wild species in their pedigrees.

Section 6 lists 74 papers, 60 abstracts, and  4 theses which report the use of NRSP-6 Solanum introductions this year.  

5.  WORK PLANNED FOR 1999

Dr. Spooner will participate in a second collecting expedition to Peru.

Evaluation experiments will be continued on Solanum species for the following traits: frost hardiness, rooting vigor, tuber calcium, late blight resistance, hormone mutants, glycoalkaloids, and fertility in heat stress.

The general objective of NRSP-6 to promote and facilitate potato research and  breeding will be pursued by continuing high quality service with respect to introduction, preservation, classification, evaluation, and distribution of potato germplasm to clients in the U.S. and around the world.

We will continue APIC intergenebank research projects determining the cause of observed differences in situ and genebank accessions, and correlations of geographic/habitat data with partitioning of diversity.

An APIC meeting is planned for December 1999 in India.  

6. PUBLICATIONS ISSUED DURING THE YEAR

A.     Publications issued by NRSP-6 Personnel

Bamberg, J.B., A.H. del Rio, and M.W. Martin.  1997.  Expanding the geographical representation of ex situ germplasm samples of wild Solanum jamesii and S. fendleri from the USA.  Am. Potato J. 74(6):416-417.  (Abstract).

Bamberg, J.B., D.J. Ormrod, and W.E. Fry.  1997.  Screening wild Solanum germplasm for resistance to late blight.  Am. Potato J. 74(6):417.  (Abstract).

Bamberg, J.B., J.P. Palta, L.A. Peterson, M.W. Martin, and A.R. Krueger.  1998.  Fine screening potato (Solanum) species germplasm for tuber calcium.  Am. J. Potato Res. 75(4):181-186.

Chen, Yu-Kuang, J.B. Bamberg, and J.P. Palta.  1997.  Cold hardiness and tuber production in progeny derived from somatic hybrids between Solanum tuberosum and  S. commersonii.  Am. Potato J. 74(6):422.  (Abstract).

Chen, Yu-Kuang, J.B. Bamberg, and J.P. Palta.  1998. Incorporation of freezing tolerance and tuber traits in sexual progeny derived from Solanum tuberosum (+) S. commersonii somatic hybrids.  Am. J. Potato Res. 75(6):273.  (Abstract).

Clausen, A.M. and D.M. Spooner.  1998.  Molecular support for the hybrid origin of the wild potato species Solanum x rechei.  Crop Sci. 38:858-865.

Del Rio, A.H. and J.B. Bamberg.  1997.  Use of rapid markers to optimize potato genebank management: Identification of a “mystery” Solanum sucrense accession.  Am. Potato J. 74(6):461-462.  (Abstract).

Del Rio, A.H. and J.B. Bamberg.  1998.  Effects of sampling size and RAPD marker heterogeneity on the estimation of genetic relationships.  Am. J. Potato Res. 75(6):275.  (Abstract).

Douches, D.S., W.W. Kirk, and J.B. Bamberg.  1997.  Fine screening wild Solanum species for resistance to late blight.  Am. Potato J. 74(6):426.  (Abstract).

Errebhi, M., C.J. Rosen, F.I. Lauer, M.W. Martin, J.B. Bamberg, and D.E. Birong.  1998.  Screening of exotic potato germplasm for nitrogen uptake and biomass production.  Am. J. Potato Res. 75(2):93-100.

Lozoya-Saldana, H., A. Hernandez, R. Flores, and J. Bamberg.  1997.  Late blight on wild Solanum species in the Toluca Valley in 1996.  Am. Potato J. 74(6):445.  (Abstract).

Rivera-Pena, A., D.M. Spooner, R.G. van den Berg, and K. Schuler.  1998.  Wild tuber-bearing species of Solanum hosts of Phytophthora infestans (Mont.) De Bary in natural habitat in Mexico.  Am. J. Potato Res. 75(6):294.  (Abstract).

Spooner, D.M., R. Hoekstra, R. van den Berg, and V. Martinez.  1998.  Solanum sect. Petota in Guatemala: Taxonomy and genetic resources.  Am. J. Potato Res. 75(1):3-17.

Spooner, D.M., V. Martinez, R. Hoekstra, and R.G. van den Berg.  1997.  Collecting of potato wild species in Guatemala.  Agro. Mesoamericana 8(2):59-66.

Spooner, D.M., A. Rivera-Pena, R. Grandenberg, and K. Schuler.  1998.  Wild potato collecting expedition in Mexico in 1997.  Am. J. Potato Res. 75(6):300.  (Abstract).

Van den Berg, R.G., J.T. Miller, M.L. Ugarte, J. Kardolus, J. Villand, J. Nienhuis, and D.M. Spooner.  1998.  Collapse of morphological species in the wild potato Solanum brevicaule complex (sect. Petota).  Am. J. Bot. 85:92-109.

Vega, Sandra E., J.B. Bamberg, and J.P. Palta.  1997.  Potential for improving freezing stress tolerance of wild potato germplasm by supplemental calcium fertilization.  Am. Potato J. 74(6):473-474.  (Abstract).

 B.     Journal Articles and Abstracts Reporting Research with NRSP-6 Stocks

Acuna, I., B. Jacobsen, and D. Corsini.  1998.  Thaxtomin-A screening assay for common scab resistance.  Am. J. Potato Res. 75(6):269.  (Abstract).

Ali-Khan, S.T., G.R. Johnston, R. Coffin, V. Currie, J. Wilson, A. McKeown, and W. Langenberg.  1998.  OAC Royal Gold: A new potato cultivar with purple skin and yellow flesh.  Am. J. Potato Res. 75(4):179-180.

Anjum, M.A. and T.A. Villiers.  1997.  Induction of microtubers in vitro from stem segments of  Solanum tuberosum L., S. commersonii Dun. and S. acaule Bitt.  Sci. Hort. 70(2/3):231-235.

Arnone, S., L. Bacchetta, S. Musmeci, R. Ciccoli, V. di Gioia, M. Cristofaro, and A. Sonnino.  1996.  Breeding potato (Solanum tuberosum L.) for resistance to Colorado potato beetle and potato tuber moth in Italy.  Resistant Pest Mgmnt. 8(1):57-59.

Arnone, S., S. Musmeci, L. Bacchetta, N. Cordischi, E. Pucci, M. Cristofaro, and A. Sonnino.  1998.  Research in Solanum ssp. of sources of resistance to the potato tuber moth Phthorimaea operculella (Zeller).  Potato Res. 41(1):39-49.

Ashiv Mehta, S.P. Trehan, and H.N. Kaul.  1997.  Calcium content in potato tuber in relation to keeping quality.  Agric. Sci. Digest 17(3):165-168.

Balbyshev, N.F. and J.H. Lorenzen.  1998.  Defoliation and tuber yield of breeding clones derived from ND2858-1.  Am. J. Potato Res. 75(6):299-270.   (Abstract).

Banfalvi, Z., A. Molnar, G. Molnar, L. Lakatos, and L. Szabo.  1996.  Starch synthesis-, and tuber storage protein genes are differently expressed in Solanum tuberosum and in Solanum brevidens.  FEBS Letters 383(3):159-164.

Barone, A., D. Carputo, G. La Rotonda, and L. Frusciante.  1997.  Discrepancy between spindle anomalies and 2n pollen production in Solanum interspecific hybrids.  Am. Potato J. 74(6):399-403.

Boluarte, T. and R.E. Veilleux.  1997.  Characterization of a backcross population for anther culture response: First step to target genes controlling androgenesis in potato.  Am. Potato J. 74(6):419.  (Abstract).

Boluarte, T. and R.E. Veilleux.  1998.  Segregation of microsatellite alleles in reciprocal backcross populations of diploid potato.  Am. J. Potato Res. 75(6):270-271.  (Abstract).

Brown, C.R., B. Schuck-Ennis, C.-P. Yang, H. Mojtahedi, and G.S. Santo.  1997.  Genetic marker analysis of introgression of resistance to Columbia root-knot nematode.  Am. Potato J. 74(6):419-420.  (Abstract).

Camadro, S.L., L.A. Verde, and O.N. Marcellan.  1998.  Pollen-pistil incompatibility in a diploid hybrid potato population with cultivated and wild germplasm.  Am. J. Potato Res. 75(2):81-85.

Cani, Eduard, V. Ashkenazi, J. Hillel, and R.E. Veilleux.  1997.  SSR analysis of the genetic composition of an anther-derived potato family.  Am. Potato J. 74(6):420-421.  (Abstract).

Cardi, T.  1998.  Multivariate analysis of variation among Solanum commersonii (+) S. tuberosum somatic hybrids with different ploidy levels.  Euphytica 99(1):35-41.

Carputo, D., M. Speggiorin, P. Garreffa, A. Raio, and L.M. Monti.  1996, publ. 1997.  Screening for resistance to tuber soft rot and blackleg in diploid Solanum species and S. tuberosum haploids.  J. Genet. Breeding 50(3):221-226.

Celebi, F., P. Russo, K. Watanabe, J.P.T. Valkonen, and S.A. Slack.  1998.  Resistance of potato to cucumber mosaic virus appears related to localization in inoculated leaves.  Am. J. Potato Res. 75(4):195-199.

Chacon, Gabriela, R.L. Plaisted, and Bill B. Brodie.  1997.  Inheritance of the resistance to pathotype Ro2 of Globodera rostochiensis.  Am. Potato J. 74(6):422.  (Abstract).

Christ, B.J. and K.G. Haynes.  1997.  General combining ability for early blight resistance from open pollinated 4x-2x early blight resistant potatoes.  Am. Potato J. 74(6):422-423.  (Abstract).

Conicella, C., G. Genualdo, R. Lucia, K.S. Ramulu, and T. Cardi.  1997.  Early tapetal degeneration and meiotic defects are involved in the male sterility of Solanum commersonii (+) S. tuberosum somatic hybrids.  Theo. Appl. Genetics 95(4):609-617.

Cutright, R.J. and R.E. Veilleux.  1997.  Derivation of monoploid potato families by anther culture and pseudogamy.  Am. Potato J. 74(6):425.  (Abstract).

Cutright, R.J. and R.E. Veilleux.  1998.  Derivation and comparison of androgenic and gynogenic monoploid potato families.  Am. J. Potato Res. 75(6):274.  (Abstract).

Davies, H.V.  1998.  Physiological mechanisms associated with the development of internal necrotic disorders of potato.  Am. J. Potato Res. 75(1):37-44.

Deahl, K.L., A. Rivera-Pena, and H. Lozoya-Saldana.  1998.  Characterization of Phytophthora Infestans populations from wild Solanum species in Mexico: Dynamics of mating types and metalaxyl sensitivity.  Am. J. Potato Res. 75(6):275.  (Abstract).

Debabrata, Sarkar and P.S. Naik.  1998.  Factors affecting minimal growth conservation of potato microplants in vitro.  Euphytica 102(2):275-280.

Dong, F., J.P. Helgeson, and J. Jiang.  1998.  Genome painting to differentiate chromosomes from different Solanum species.  Am. J. Potato Res. 75(6):275-276.  (Abstract).

Gamarra, D.C., V.H.P. Bueno, J.C. Moraes, and A.M. Auad.  1998.  Influence of glandular trichomes of Solanum berthaultii on the predation of Scymnus (Pullus) argentinicus (Weise) (Coleoptera: Coccinellidae) on Myzus persicae (Sulzer) (Homoptera: Aphididae).  Anais da Sociedade Ent. do Brasil 27(1):59-65.

Garcia, D., M.E. Gonzalez, and O. Sam.  1996.  Several characteristics associated with ploidy in potato.  Cultivos Tropicales 17(1):65-66.

Haberlach, G.T., S.K. Naess, S.M. Wielgus, J.A. Raasch, and J.P. Helgeson.  1998.  Late blight trials in the UW Biotron identify resistant and susceptible clones in potato breeding populations.  Am. J. Potato Res. 75(6):278.  (Abstract).

Hamalainen, J.H., V.A. Sorri, K.N. Watanabe, C. Gebhardt, and J.P.T. Valkonen.  1998.  Molecular examination of a chromosome region that controls resistance to potato Y and A potyviruses in potato.  Theo. Appl. Genetics 96(8):1036-1043.

Hamernik, A.J. and R.E. Hanneman, Jr.  1998.  Breeding 2x haploid X species potatoes that chip from 2 C cold storage.  Am. J. Potato Res. 75(6):278-279.  (Abstract).

Hanneman, Jr., R.E.  1997.  Building blocks for enhancement.  Am. Potato J. 74(6):433-434.  (Abstract).

Hanneman, Jr., Robert E.  1998.  Wild species – the golden nuggets of nature.  Am. J. Potato Res. 75(6):279.  (Abstract).

Hassanein, A.M., K.A. Fayez, and A.M. Ahmed.  1998.  Physiological studies on nuclear-organelle interaction of cybrid plants containing Solanum nigrum genome and Solanum tuberosum plastome.  Phyton (Horn) 37(2):167-179.

Hawkes, J.G.  1997.  Cultivated plant diversity and taxonomy.  In Species: The units of biodiversity (Eds. M.F. Claridge, H.A. Dawah, M.R. Wilson; London, UK, Chapman & Hall Ltd. 191-198.

Haynes, K.G. and B.J. Christ.  1998.  Genetic variation for resistance to Phytophthora Infestans in a diploid Solanum phureja-S. stenotomum hybrid potato population in Pennsylvania.  Am. J. Potato Res. 75(6):279.  (Abstract).

Haynes, K.G., R.W. Goth, and R.J. Young.  1997.  Genotype x environment interactions for resistance to common scab in tetraploid potato.  Crop Sci. 37(4):1163-1167.

Haynes, K.G., D.H. Lambert, B.J. Christ, D.P. Weingartner, D.S. Douches, J.E. Backlund, G. Secor, W.Fry, and W. Stevenson.  1998.  Phenotypic stability of resistance to late blight in potato clones evaluated at eight sites in the United States.  Am. J. Potato Res. 75(5):211-217.

Helgeson, J.P., G.T. Haberlach, J.M. McGrath, J.A. Raasch, S.K. Naess, and S.M. Wielgus.  1997.  A RAPD marker linked to late blight resistance derived from Solanum bulbocastanum-potato somatic hybrids.  Am. Potato J. 74(6):434-435.  (Abstract).

Helgeson, J.P., J.D. Pohlman, S. Austin, G.T. Haberlach, S.M. Wielgus, D. Ronis, L. Zambolim, P. Tooley, J.M. McGrath, R.V. James, and W.R. Stevenson.  1998.  Somatic hybrids between Solanum bulbocastanum and potato: A new source of resistance to late blight.  Theor. Appl. Genetics 96(6/7):738-742.

Hosaka, K. and R.E. Hanneman, Jr.  1998.  Genetics of self-compatibility in a self-incompatible wild diploid potato species Solanum chacoensei.  1. Detection of an S locus inhibitor (Sli) gene.  Euphytica 99(3):191-197.

Huaman, Z.  1998.  Collection, maintenance and evaluation of potato genetic resources.  Plant Varieties & Seeds 11(1):29-38.

Jansky, Shelley.  1998.  Breeding for Verticillium wilt resistance.  Am. J. Potato Res. 75(6):280.  (Abstract).

Jansky, S.H., S. Austin-Hillips, and C. McCarthy.  1998.  Colorado potato beetle resistance in somatic hybrids of diploid interspecific Solanum clones.  Hort. Science. (Accepted).

Jansky, S.H., A.E. MacGuidwin, and D.I. Rouse.  1998.  The effect of root lesion nematodes on Verticillium resistant potato clones.  The Badger CommonTater 50(8):14-15.

Janssen, G.J.W.  1997.  Fighting root-knot nematodes with resistance from wild potato species.  Pesticide Outlook 8(5):29-31.

Janssen, G.J.W., A. van Norel, B. Verkerk-Bakker, and R. Janssen.  1997.  Intra- and interspecific variation of root-knot nematodes, Meloidogyne spp., with regard to resistance in wild tuber-bearing Solanum species.  Fund’l. Appl. Nematology 20(5):449-457.

Johnson, J. and S.H. Jansky.  1998.  The battle against early dying disease.  The Badger CommonTater 50(8):20-23.

Kardolus, J.P. and N. Groendijk-Wilders.  1998.  The inflorescence architecture of Solanum acaule and related taxa of Solanum section Petota (Solanaceae).  Acta Botanica Neerlandica 47(2):195-207.

Kardolus, J.P., H.J. van Eck, and R.G. van den Berg.  1998.  The potential of AFLPs in biosystematics: A first application in Solanum taxonomy (Solanaceae).  Pl. Syst. Evolution 210(1/2):87-103.

Kisha, T.J., D.S. Douches, E.J. Grafius, and W.L. Pett.  1998.  Effectiveness of host plant resistance traits in potato to the Colorado potato beetle.  Am. J. Potato Res. 75(6):282.  (Abstract).

Kowalski, S.P., J.M. Domek, F.G. Perez, L.L. Sanford, and K.L. Deahl.  1997.  Foliar glycoalkaloids as resistance factors to the Colorado potato beetle: Studies using synthetic diets.  Am. Potato J. 74(6):441.  (Abstract).

Kowalski, S.P., G.C. Yencho, R.S. Kobayashi, F.G. Perez, S.L. Sinden, and K.L. Deahl.  1997.  QTL analyses as a tool to study biosynthetic pathways: Mapping of solanidine and solasodine genes in potato.  Am. Potato J. 74(6):441-442.  (Abstract).

Kuhl, J.C., R.E. Hanneman, Jr., and M.J. Havey.  1998.  Investigation of resistance to Phytophthora Infestans in 2X(1EBN) wild potato species.  Am. J. Potato Res. 75(6):282.  (Abstract).

Laferriere, L., C. Allen, and J.P. Helgeson.  1998.  Developing bacterial wilt resistant breeding lines from Solanum tuberosum/S. commersonii somatic hybrids.  Am. J. Potato Res. 75(6):282-283.  (Abstract).

Lafta, A.M. and J.H. Lorenzen.  1998.  Glycoalkaloid levels in potato leaves in response to low light and high temperature.  Am. J. Potato Res. 75: (Abstract).

Larrain, P., J. Kalazich, R. Plaisted, W. Tingey, and C. Vasquez.  1998.  High levels of resistance to potato tuber moth Phthorimaea Operculella (Zeller) (Lepidoptera: Gelechidae) found in adapted trichome-derived germplasm.  Am. J. Potato Res. 75(6):283.  (Abstract).

Lawson, D.R., T.P. Green, L.W. Haynes, and A.R. Miller.  1997.  Nuclear magnetic resonance spectroscopy and mass spectrometry of solanidine, leptinidine, and acetylleptinidine.  Steroidal alkaloids from Solanum chacoense Bitter.  J. Ag. Food Chem. 45(10):4122-4126.

Lewis, C.E., J.R.L. Walker, J.E. Lancaster, and K.H. Sutton.  1998.  Determination of anthocyanins, flavonoids and phenolic acids in potatoes.  II: wild, tuberous Solanum species.  J. Sci. Food & Agric. 77(1):58-63.

Li, X, H.J. van Eck, J.N.A.M. Rouppe van der Voort, D.J. Huigen, P. Stam, and E. Jacobsen.  1998.  Autotetraploids and genetic mapping using common AFLP markers: the R2 allele conferring resistance to Phytophthora infestans mapped on potato chromosome 4.  Theor. Appl. Genetics 96(8):1121-1128.

Longtine, Craig, J. Bachlund, C.A. Thill, E.T. Radcliffe, and D.W. Ragsdale.  1998.  Breeding potatoes resistant to potato leafhopper.  Am. J. Potato Res. 75(6):284-285.  (Abstract).

Love, S.L., J.J. Pavek, A. Thompson-Johns, and W. Bohl.  1998.  Breeding progress for potato chip quality in North American cultivars.  Am. J. Potato Res. 75(1):27-36.

Lynch, D., L. Kawchuk, and J. Hachey.  1998.  A single gene in Solanum chacoense confers a high level of resistance to Verticillium wilt.  Am. J. Potato Res. 75(6):286.  (Abstract).

Lynch, D.R., L.M. Kawchuk, J. Hachey, P.S. Bains, and R.J. Howard.  1997.  Identification of a gene conferring high levels of resistance to Verticillium wilt in Solanum chacoense.  Pl. Disease 81(9):1011-1014.

Maine, M. J. de.  1997.  The male fertility of primary and further generation dihaploids of Solanum tuberosum.  Potato Res. 40(1):59-68.

Maine, M.J. de, A.K. Lees, and J.E. Bradshaw.  1998.  Soft-rot resistance combined with other tuber characters in long day-adapted Solanum phureja.  Potato Res. 41(1):69-82.

Matsumoto, A., S. Imanishi, M. Hossain, A. Escalante, and H. Egashira.  1997.  Fertile somatic hybrids between F₁ (Lycopersicon esculentum x L. peruvianum var. humifusum) and Solanum lycopersicoides.  Breeding Sci. 47(4):327-333.

Na, Jong-Kuk and Hak-Tae Lim.  1998.  High efficient plant regeneration and transformation of Btt gene into several potato cultivars and wild potato species.  Am. J. Potato Res. 75(6):289.  (Abstract).

Naess, S.K., G.T. Haberlach, S.M. Wielgus, J.A. Raasch, and J.P. Helgeson.  1998.  Marker assisted breeding for late blight resistance in potato.  Am. J. Potato Res. 75(6):289-290.  (Abstract).

Naito, K., Y. Umemura, M. Mori, T. Sumida, T. Okada, N. Takamatsu, Y. Okawa, K. Hayashi, N. Saito, and T. Honda.  1998.  Acylated pelargonidin glycosides from a red potato.  Phytochemistry 47(1):109-112.

Novy, Richard and C.L. Longtine.  1997.  Solanum Etuberosum: A potential source of resistance to green peach aphid, potato leafroll virus, and potato virus Y.  Am. Potato J. 74(6):452.  (Abstract).

Novy, Richard and C.L. Longtine.  1998.  Aphid and virus resistance in potato clones derived from Solanum etuberosum.  Am. J. Potato Res. 75(6):291.  (Abstract).

Novy, R.G., G.A. Secor, B.L. Farnsworth, J.H. Lorenzen, E.T. Holm, D.A. Preston, N.C. Gudmestad, and J.R. Sowokinos.  1998.  NorValley: A white-skinned chipping cultivar with cold-sweetening resistance.  Am. J. Potato Res. 75(2):101-105.

Nyman, M. and S. Waara.  1997.  Characterization of somatic hybrids between Solanum tuberosum and its frost-tolerant relative Solanum commersonii.  Theor. Appl. Genetics 95(7):1127-1132.

Olmstead, R.G. and J.D. Palmer.  1997.  Implications for the phylogeny, classification, and biogeography of  Solanum from cpDNA restriction site variation.  Systematic Botany 22(1):19-29.

Oltmans, Shannon and R.G. Novy.  1998.  Development of cold chipping potato cultivars by the use of wild species.  Am. J. Potato Res. 75(6):291.  (Abstract).

Ortiz, R., M. Iwanaga, and S.J. Peloquin.  1997.  Evaluation of FDR diploid and tetraploid parents in potato under two different day-length environments.  Pl. Breeding 116(4):353-358.

Padliskikh, B. Ya, A.V. Varankova, N.V. Kalashnikava, A.V. Sauchuk, V.L. Padliskikh, and A.P. Yarmishyn.  1995.  Study on fertility of potato dihaploids.  Seriya Biyalagichnykh Navuk 2:43-49.

Pavek, Joseph J. and D.L. Corsini.  1997.  A86SXD6-7: A cold chipping diploid parent with 2N pollen.  Am. Potato J. 74(6):454.  (Abstract).

Paz, M.M. and R.E. Veilleux.  1997.  Genetic diversity based on randomly amplified polymorphic DNA (RAPD) and its relationship with the performance of diploid potato hybrids.  J. Am. Soc. Hort. Sci. 122(6):740-747.

Pelletier, Yvan.  1997.  Identification of the mode of resistance to the Colorado potato beetle in wild Solanum species.  Am. Potato J. 74(6):455.  (Abstract).

Pineda, Omaira, R.L. Plaisted, and S.D. Tanksley.  1997.  Identification of RFLP markers linked to loci conferring resistance to the potato cyst nematode Globodera Pallida.  Am. Potato J. 74(6):458.  (Abstract).

Plaisted, R.L., D.E. Halseth, B.B. Brodie, S.A. Slack, J.B. Sieczka, B.J. Christ, K.M. Paddock, and M.W. Peck.  1998.  Andover: An early to midseason golden nematode resistant variety for use as chipstock or tablestock.  Am. J. Potato Res. 75(3):113-116.

Plaisted, R.L., D.E. Halseth, B.B. Brodie, S.A. Slack, J.B. Sieczka, B.J. Christ, K.M. Paddock, and M.W. Peck.  1998.  Pike: A full season scab and golden nematode resistant chipstock variety.  Am. J. Potato Res. 75(3):117-120.

Rai, S. and J.H. Lorenzen.  1998.  Identification of AFLP markers linked to covalently-bound phosphate in potato starch.  Am. J. Potato Res. 75(6):293.   (Abstract).

Ramon, M. and R.E. Hanneman, Jr.  1998.  Introgression of resistance to Colorado potato beetle from wild diploid species to cultivated potato.  Am. J. Potato Res. 75(6):294.  (Abstract).

Ramon, M. and R.E. Hanneman, Jr.  1998.  Meiotic chromosome pairing in a Solanum tuberosum x Solanum pinntisectum hybrid.  Am. J. Potato Res. 75(6):294.  (Abstract).

Ramon, M., F.C. Serquen, and R.E. Hanneman, Jr.  1997.  A hybrid between a S. tuberosum Gp. Tuberosum haploid and S. pinnatisectum.  Am. Potato J. 74(6):460-461.  (Abstract).

Reeves, A.F., G.A. Porter, T.M. Work, D.H. Lambert, A.A. Davis, and E.S. Plissey.  1997.  Mainestay: a high-yielding, round white potato variety for fresh market.  Am. Potato J. 74(4):255-263.

Romero Angulo, H.M. and J.A. Norato Rodriguez.  1996.  Effect of polyamines in protecting creole potatoes (Solanum phureja cv. Yema de Huevo) against frost.  Agro. Colombiana 13(1):50-55.

Ronning, C.M., L.L. Sanford, J.R. Stommel, F.G. Perez, and K.L. Deahl.  1997.  Inheritance of leptine production in Solanum chacoense.  Am. Potato J. 74(6):462-463.  (Abstract).

Ronning, C.M., L.L. Sanford, R.S. Kobayashi, and S.P. Kowalski.  1998.  Foliar leptine production in segregating F₁, inter-F₁, and backcross families of Solanum chacoense Bitter.  Am. J. Potato Res. 75(3):137-143.

Rorat, T., W. Irzykowski, and W.J. Grygorowicz.  1997.  Identification and expression of novel cold induced genes in potato (Solanum sogarandinum).  Plant Sci. 124(1):69-78.

Ruiz de Galarreta, J.I., A. Carrasco, A. Salazar, I. Barrena, E. Iturritxa, R. Marquinez, F.J. Legorburu, and E. Ritter.  1998.  Wild Solanum species as resistance sources against different pathogens of potato.  Potato Res. 41(1):57-68.

Sanford, L.L. S. Kowalski, K.L. Deahl, and C. Ronning.  1997.  Glycoalkaloid contents of tetraploid Solanum chacoense X S. tuberosum F₂ hybrid and backcross genotypes.  Am. Potato J. 74(6):463-464.  (Abstract).

Sanford, L.L., S.P. Kowalski, C.M. Ronning, and K.L. Deahl.  1998.  Leptines and other glycoalkaloids in tetraploid Solanum tuberosum x Solanum chacoense F₂ hybrid and backcross families.  Am. J. Potato Res. 75(4):167-172.

Seppanen, M.M., M. Majaharju, S. Somersalo, and E. Pehu.  1998.  Freezing tolerance, cold acclimation and oxidative stress in potato.  Paraquat tolerance is related to acclimation but is a poor indicator of freezing tolerance.  Phys. Plant. 102(3):454-460.

Serquen, Felix C. and R.E. Hanneman, Jr.  1997.  Detection of gene flow between wild and cultivated potato species using RAPD markers.  Am. Potato J. 74(6):465-466.  (Abstract).

Shikanai, T., H. Kaneko, S. Nakata, K. Harada, and K. Watanabe.  1998.  Mitochondrial genome structure of a cytoplasmic hybrid between tomato and wild potato.  Plant Cell Reports 17(11):832-836.

Song, Junqi and J.Jiang.  1997.  Toward a potato bacterial artificial chromosome library.  Am. Potato J. 74(6):468.  (Abstract).

Song, Junqi, F. Dong, and J. Jiang.  1998.  Construction and characterization of a potato bacterial artificial chromosome library.  Am. J. Potato Res. 75(6):298.  (Abstract).

Song, Ye-Su and H. Lim.  1998.  Screening cultivars with less-browning tubers and utilization of non-browning wild species for the development of bruising resistant potato clones.  Am. J. Potato Res. 75(6):298-299.  (Abstract).

Song, Ye-Su, A. Schuarzfischer, Rokka Veli-Matti, Eija A. Pehu, and Hak-Tae Lim.  1998.  Production of characterization of somatic hybrids between dihaploid lines and Solanum etuberosum and brevidence.  Am. J. Potato Res. 75(6):300.  (Abstract).

Sotelo, A., E. Contreras, H. Sousa, and V. Hernandez.  1998.  Nutrient composition and toxic factor content of four wild species of Mexican potato.  J. Agric. Food Chem. 46(4):1355-1358.

Swiezynski, K.M., L. Domanski, M. Osiecka, M.T. Sieczka, and H. Zarzycka.  1997.  Resistance to Phytophthora infestans in diploid and tetraploid potato families.     1.  Resistance in detached leaflets.  J. Appl. Genetics 38(1):19-32.

Swiezynski, K.M., B. Flis, M. Osiecka, M.T. Sieczka, and H. Zarzycka.  1997.  Resistance to Phytophthora infestans in diploid and tetraploid potato families.     2.  Resistance in tubers.  J. Appl. Genetics 38(1):33-44.

Teparkum, S. and R.E. Veilleux.  1998.  Indifference of potato anther culture to colchicine and genetic similarity among anther-derived monoploid regenerants determined by RAPD analysis.  Pl. Cell, Tissue, Organ Culture 53(1):49-58.

Thieme, R., U. Darsow, T. Gavrilenko, D. Dorokhov, and H. Tiemann.  1997.  Production of somatic hybrids between S. tuberosum L. and late blight resistant Mexican wild potato species.  Euphytica 97(2):189-200.

Tommiska, T.J., J.H. Hamalainen, K.N. Watanabe, and J.P.T. Valkonen.  1998.  Mapping of the gene Nx_phu that controls hypersensitive resistance to potato virus X in Solanum phureja IvP35.  Theor. Appl. Genetics 96(6/7):840-843.

Valkonen, J.P.T.  1997.  Novel resistances to four potyviruses in tuber-bearing potato species, and temperature-sensitive expression of hypersensitive resistance to potato virus Y.  Ann. Appl. Bio. 130(1):91-104.

Veilleux, R.E., M.M. Paz, and D. Levy.  1997.  Potato germplasm development for warm climates: genetic enhancement of tolerance to heat stress.  Heat tolerant 4x-2x hybrids.  Euphytica 98(1/2):83-92.

Veilleux, Richard E. and S. M. Piovano.  1998.  Recurrent selection for monoploid and doubled monoploid potato germplasm.  Am. J. Potato Res. 75(6):302.  (Abstract).

Westedt, A.L., D.S. Douches, W. Pett, E.J. Grafius.  1998.  Evaluation of natural and engineered resistance mechanisms in Solanum tuberosum for resistance to Phthorimaea operculella (Lepidoptera: Gelechiidae).  J. Eco. Ent. 91(2):552-556.

Yamada, T., K. Hosaka, K. Nakagawa, N. Kaide, S. Misoo, and O. Kamijima.  1998.  Nuclear genome constitution and other characteristics of somatic hybrids between dihaploid Solanum acaule and tetraploid S. tuberosum.  Euphytica 102(2):239-246.

Yamada, T., S. Misoo, T. Ishii, Y. Ito, K. Takaoka, and O. Kamijima.  1997.  Characterization of somatic hybrids between tetraploid Solanum tuberosum L. and dihaploid S. acaule.  Breeding Science 47(3):229-236.

Zhang, YanLing and D.J. Donnelly.  1997.  In vitro bioassays for salinity tolerance screening of potato.  Potato Res. 40(3):285-295.

Zimmerer, K.S.  1998.  The ecogeography of Andean potatoes.  BioScience 48(6):445-454.

C.   Theses Reporting Research with NRSP-6 Stocks

Beek, J.G. van der.  1997.  Interaction between root-knot nematodes and Solanum spp.: variation in pathogenicity, cytology, proteins and DNA.  Thesis.  Wageningen Agricultural University, Wageningen, Netherlands.  219 pp.

Hamernik, Andy J.  1998.  Breeding 2x haploid x species hybrid potatoes that chip from 2°C cold storage.  M.S. Thesis.  University of Wisconsin, Madison, WI.  208 pp.

Rai, S.R.  1998.  Molecular mapping of covalently-bound phosphate in potato starch.  Ph.D. Dissertation.  North Dakota State University, Fargo, ND.  130 pp.

Ramon, M.   1998.   Evaluation of resistance to late blight (Phytophtora infestans) and Colorado potato beetle (Leptinotarsa decemlineata) in hybrids between Solanum wild species and Solanum tuberosum subsp. tuberosum haploids. Ph.D. Thesis. University of Wisconsin, Madison, WI. 174p.

Tian, X.  1998.  Application of RFLP subtraction in plant genetic investigations.  M.S. Thesis.  North Dakota State University, Fargo, ND.  83 pp.

7.  APPROVED

            A. R. Mosley, Chairman, Technical Committee                    Date

            R. L. Lower, Lead Administrative Advisor                            Date