ANNUAL  REPORT
Calendar Year 1999

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 Rafael Vinci (INIA, Peru) participated in a successful expedition to collect wild species of potato in Peru from March 8^th to April 25^th, 1999. This collection trip resulted in 101 new accessions of  Solanum species.

Dr. Bamberg, in collaboration with Charles Fernandez (US Potato Genebank), Stephen Kiru (VIR, St. Petersburg, Russia), Joseph Pavek (ARS Potato Breeder, Aberdeen, Idaho), and Sylvia Pavek (wife of ARS potato breeder), participated in a successful expedition to the southwest United States to obtain new materials for the collaborative intergenebank research project.

A total of 145 accessions were assigned PI numbers in 1999, and are now available from the NRSP-6 Solanum germplasm collection: 80 in vitro clones, 58 quarantine clones, and seven accessions from the southwest United States.

In 1999, 91 new accessions were planted out in the spring quarantined increase. Of the 91 accessions, 62 germinated. Fifty-eight of these were released and added into the collection (four were virus suspect and not released).  Of the 58 accessions, 41 were from Spooner's 1997 Mexico collection, 16 were from Spooner's 1998 Peru collection, and one from the 1992 Columbia collection trip.

A total of 88 clones were added to the in vitro collection in 1999 as foreign varieties or genetic stocks. 

B.  Preservation and Increase of Stocks

In 1999, 178 accessions were increased as botanical seed populations.

This year a total of 720 potato spindle tuber viroid (PSTV) tests were performed on seed increase parents, seed lots and research materials. Germination tests were performed on 993 accessions, and ploidy determinations were done on 97 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 5,132 units of seed, 21 tuber families and 809 in vitro stocks to clientele in 18 states of the United States and 10 other countries.  Internally, NRSP-6 used 9,931 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).

² Includes 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 1999 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 1999.

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, has been submitted for publication. 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 was held in conjunction with the Global Potato Conference in New Delhi, December, 1999.  APIC members largely organized and presented the papers for the session: "Genetic Resources and Crop Improvement".

G.    Visitors From Other Countries

Dr. Peter Dolnicar                       Ljubjana,  Slovenija
       Dr. Janet Seabrook                     Fredricton, New Brunswick, Canada
       Dr. Lin Gau                                 Fredricton, New Brunswick, Canada
       Dr. Quin Chen                             Lethbridge, Alberta, Canada
       Dr.  Ana Peralta                          Uruguay
       Dr.  Beatriz Melcho                     Uruguay
       Dr.  Luis Curbelo                         Uruguay
       Dr.  Carlos Colafranceschi           Uruguay

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.

Two cultivar releases were published in the American Journal of Potato Research in 1999: ‘Quaggy Joe’, and ‘Reba’.  Both are known to have wild species in their pedigrees.

Section 6 lists 89 papers, 30 abstracts, and 3 theses which report the use of NRSP-6 Solanum introductions this year.  

5.  WORK PLANNED FOR 2000

Dr. Spooner will participate in a third 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.  

6. PUBLICATIONS ISSUED DURING THE YEAR

A.        Publications issued by NRSP-6 Personnel

Bamberg, J.B.  1999.  Dependence on exogenous gibberellin for seed germination in Solanum acaule Bitter and other Solanum (potato) species.  Am. J. Potato Res. 76(6):351-355.

Bamberg, J.B.  1999.  Screening for gibberellin deficiency mutants in Solanum tuberosum ssp. andigena.  Am. J. Potato Res. 76(5):321-322.

Bamberg, J.B.  1999.  Wild potatoes on public lands of the Southwest.  NRSP-6 brochure.

Bamberg, J.B. and A.H. del Rio.  1999.  Vulnerability of alleles in the US Potato Genebank extrapolated from RAPDS.  Am. J. Potato Res. 76(6):363-364. (Abstract)

Bamberg, J.B., A. H. del Rio and Z. Huaman.  1999.  Intergenebank Cooperation in Genetic Diversity Conservation Research.  Presented: Symposium of Potato Assn. of American Annual Meeting, 1999.

Bamberg, J.B., A. H. del Rio and Z. Huaman.  1999.  Intergenebank Cooperation in Genetic Diversity Conservation Research.  Presented: Global Conference on Potato, New Delhi, India, December 6-12, 1999.

Chen, Y.-K., J.B. Bamberg and J. Palta.  1999.  Expression of freezing tolerance in the interspecific F₁ and somatic hybrids of potatoes.  Theor. Appl. Genet. 98(6/7):995-1004.

Chen, Y.-K., J. Palta and J.B. Bamberg.  1999.  Freezing tolerance and tuber production in self and backcross progenies derived from somatic hybrids between Solanum tuberosum L. and S. commersonii Dun.  Theor. Appl. Genet. 99:100-107.

Chen, Y.K.H., J.P. Palta, J.B. Bamberg, Kim HeiYoung, G.T. Haberlach, and J.P. Helgeson.  1999.  Expression of nonacclimated freezing tolerance and cold acclimation capacity in somatic hybrids between hardy wild Solanum species and cultivated potatoes.  Euphytica 107(1):1-8.

Del Rio, Alfonso H. and John B. Bamberg.  1999.  Association of ecogeographical variables with patterns of genetic variation in native wild US potato populations determined by RAPD markers.  Am. J. Potato Res. 76(6):367-368.  (Abstract)

Errebhi, M., C.J. Rosen, F.I. Lauer, M.W. Martin, and J.B. Bamberg.  1999.  Evaluation of tuber-bearing Solanum species for nitrogen use efficiency and biomass partitioning.  Am. J. Potato Res. 76(3):143-151.

Huaman, Z., R. Hoekstra and J.B. Bamberg.  1999.  History of APIC and the initiative to create comprehensive databases.  Presented: Symposium of Potato Assn. of America Annual Meeting, 1999.

Miller, J.T. and D.M. Spooner.  1999.  Collapse of species boundaries in the wild potato Solanum brevicaule complex (Solanaceae, S. sect. Petota): molecular data.  Plant Systematics & Evolution 214(1/4):103-130.

Salas, A., D.M. Spooner, Z. Huaman, R.V. Torres, R. Hoekstra, K. Schuler, and R.J. Hijmans.  1999.  Report of wild potato collecting expedition to Peru, 1999.  Report to NCR-84, December 6-7, 1999, Minneapolis, Minnesota.

Spooner, D.M.  1999.  Plant genetic resources for food and agriculture in situ and ex situ: Where are the genes of importance for food security likely to come from?  Pp. 133-164.  Proceedings of an International Workshop, Inter-Dependence and Food Security: Which List of Plant Genetic Resources for Food and Agriculture for the Future Multilateral System?, Ministero Affari Esteri, Instituto Agronomico per L'Oltremare, Florence, Italy, October 1-3, 1998.

Spooner, D.M., A.S. Lopez, Z. Huaman, and R.J. Hijmans.  1999.  Wild potato collecting expedition in Southern Peru (Departments of Apurimac, Arequipa, Cusco, Moquegua Puno, Tacna) in 1998: Taxonomy and new genetic resources.  Am. J. Potato Res. 76(3):103-119.

Spooner, D.M., R.M. Olmstead, and L.A. Bohs.  1999.  Current data on the systematics of the solanaceae, with a focus on tomatoes and potatoes.  IV Plant and Animal Genome Conference Proceedings Abstract: 67.

Spooner, D.M., A. Salas, Z. Huaman, R.V. Tores, and R. Hijmans.  1999.  Report of wild potato collecting expedition to Peru, 1999.  Report to NCR-84, December 6-7, 1999, Minneapolis, Minnesota.

Spooner, D.M. and R.G. van den Berg.  1999.  Species boundaries in Central American members of Solanum series Conicibaccata.

Thill, Christian A., E.B. Radcliffe, D.W. Ragsdale, R.E. Hanneman, Jr., and J.B. Bamberg.  1999.  The identification of aphid resistant 4X potato germplasm for use in breeding.  Am. J. Potato Res. 76(6):385-386.  (Abstract)

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

Alfano, F., M. Cammareri, A. Errico, L. Frusciante, and C. Conicella.  1999.  2n gametes in Solanum tuberosum dihaploids.  Am. J. Potato Res. 76(5):281-285.

Alfano, F., M. Cammareri, D. Carputo, A. Errico, and C. Conicella.  1998.  The role of the cytoskeleton in potato meiosis.  In: Breeding research on potatoes.  Proceedings of an international symposium, June 23-26, 1998, Gross Lusewitz, Rostock, Germany. (Ed: K. Peter). 4(2):1-2.

Anjum, M.A., A. Muhammad, and T.A. Villiers.  1996.  Growth of potato axillary bud cultures in vitro.  Pakistan J. Ag. Sci. 33(1/4):6-8.

Araji, A.A.  1999.  The benefit of public investments in potato research.  Am. J. Potato Res. 76(6):363.  (Abstract)

Aziz, A.N., J.E.A. Seabrook, and G.C.C. Tai.  1999.  Amplification of RAPD markers from single pollen grains of diploid (2N=2X=24) potato.  Am. J. Potato Res. 76(4):179-182.

Aziz, A.N., J.E.A. Seabrook, G.C.C. Tai, and H. DeJong.  1999.  Screening diploid Solanum genotypes responsive to different anther culture conditions and ploidy assessment of anther-derived roots and plantlets.  Am. J. Potato Res. 76(1):9-16.

Bains, P.S., V.S. Bisht, D.R. Lynch, L.M. Kawchuk, and J.P. Helgeson.  1999.  Identification of stem soft rot (Erwinia carotovora subspecies atroseptica) resistance in potato.  Am. J. Potato Res. 76(3):137-141.

Banfalvi, Z., A. Molnar, L. Lakatos, H. Hesse, and R. Hofgen.  1999.  Differences in sucrose-to-starch metabolism of Solanum tuberosum and Solanum brevidens.  Pl. Sci. 147(1):81-88.

Barone, A., A. Sebastiano, and D. Carputo.  1999.  Chromosome pairing in Solanum commersonii-S. tuberosum sexual hybrids detected by commersonii-specific RAPDs and cytological analysis.  Genome 42(2):218-224.

Basile, B., D. Carputo, A. Zoina, L. Monti, and T. Cardi.  1998.  Solanum commersonii (+) Solanum tuberosum somatic hybrids: fertility in inter-EBN backcrosses and evaluation of progenies. In: Breeding research on potatoes.  Proceedings of an international symposium, June 23-26, 1998, Gross Lusewitz, Rostock, Germany. (Ed: K. Peter). 4(2):14-15.

Bastiaanssen, H.J.M.; P.M.M.M. van den Berg, P. Lindhout, E. Jacobsen, and M.S. Ramanna.  1998.  Postmeiotic restitution in 2n-egg formation of diploid potato.  Heredity 81(1):20-27.

Brown, C.R., M. McNabnay, and B. Dean.  1999.  Genetic characterization of reduced melanin formation in tuber tissue of Solanum hjertingii and hybrids with cultivated diploids.  Am. J. Potato Res. 76(1):37-43.

Boluarte, Tatiana and Richard E. Veilleux.  1999.  Molecular markers linked to anther culture response and leptine content in three backcross families derived from Solanum phureja and  S. chacoense.  Am. J. Potato Res. 76(6):365.  (Abstract)

Bradeen, James M., S. Kristine Naess, Susan M. Wielgus, Geraldine T. Haberlach, and John P. Helgeson.  1999.  Late blight resistance from Solanum bulbocastanum: Towards fine mapping and BAC clone isolation.  Am. J. Potato Res. 76(6):365.  (Abstract)

Brown, C.R., H. Mojtahedi, and G.S. Santo.  1999.  Genetic analysis of resistance to races 1 and 2 of Meloidogyne chitwoodi derived from the Mexican wild species Solanum hougasii.  Am. J. Potato Res. 76(6):365-366.  (Abstract)

Buso, J.A., L.S. Boiteux, and S.J. Peloquin.  1999.  Multitrait selection system using populations with a small number of interploid (4x-2x) hybrid seedlings in potato: degree of high-parent heterosis for yield and frequency of clones combining quantitative agronomic traits.  Theor. Appl. Genet. 99(1/2):81-91.

Buso, J.A., L.S. Boiteux, and S.J. Peloquin.  1999.  Comparison of haploid Tuberosum Solanum chacoense versus Solanum phureja haploid Tuberosum hybrids as staminate parents of 4x-2x progenies evaluated under distinct crop management systems.  Euphytica 109:191-199.

Buso, J.A., L.S. Boiteux, G.C.C. Tai, and S.J. Peloquin.  1999.  Chromosome regions between centromeres and proximal crossovers are the physical sites of major effect loci for yield in potato: Genetic analysis employing meiotic mutants.  Proc. Natl. Acad. Sci. 96:1773-1778.

Buso, J.A., F.J.B. Reifschneider, L.S. Boiteux, and S.J. Peloquin.  1999.  Effects of 2n-pollen formation by first meiotic division restitution with and without crossover on eight quantitative traits in 4x-2x potato progenies.  Theor. Appl. Genet. 98(8):1311-1319.

Carputo, D.  1999.  Post-zygotic gametic selection due to endosperm balance number explains unusual chromosome numbers of 3x x 2x progeny in Solanum.  Sexual Pl. Repro. 12(1):27-31.

Carputo, D., A. Barone, T. Cardi, P. Garreffa, and L. Frusciante.  1997.  True potato seed (TPS) as an alternative technique for potato production in the Mediterranean area.  (En, it, 15 ref.)  Dept. Agronomy and Plant Genetics, University of Naples, Portici, Italy. 31:29-37.

Carputo, D., L. Monti, J.E. Werner, and L. Frusciante.  1999.  Uses and usefulness of endosperm balance number.  Theor. Appl. Genet. 98(3/4):478-484.

Carputo, D., P. Garreffa, M. Mazzei, L. Monti, and T. Cardi.  1998.  Fertility of somatic hybrids Solanum commersonii (2x, 1EBN) (+) S. tuberosum haploid (2x, 2EBN) in intra- and inter-EBN crosses.  Genome 41(6):776-781.

Carputo, D., T. Cardi, L. Frusciante, P. Sirianni, S. Vega, and J.P. Palta.  1998.  Transfer of resistance genes from Solanum commersonii (2n=24, 1EBN) to S. tuberosum (2n=48, 4EBN) through ploidy and EBN manipulation. In: Breeding research on potatoes.  Proceedings of an international symposium, June 23-26, 1998, Gross Lusewitz, Rostock, Germany. (Ed: K. Peter). 4(2):16-21.

Carrera, E., S.D. Jackson, and S. Prat.  1999.  Feedback control and diurnal regulation of gibberellin 20-oxidase transcript levels in potato.  Pl. Phys. 119(2):765-773.

Chacon, M.G., R.L. Plaisted, and B.B. Brodie.  1999.  Inheritance of the resistance to Globodera rostochiensis pathotype Ro2 in potato.  Am. J. Potato Res. 76(6):345-349.

Corsini, D., J. Pavek, C. Brown, D. Inglis, M. Martin, M. Powelson, A. Dorrance, and H. Lozoya-Saldana.  1999.  Late blight resistant potato germplasm release AWN86514-2.  Am. J. Potato Res. 76(1):45-49.

DeJong, H., L.M. Kawchuk, and V.J. Burns.  1998.  Inheritance and mapping of a light green mutant in cultivated diploid potatoes.  Euphytica 103(1):83-88.

Dong, F., R.G. Novy, J.P. Helgeson, and J. Jiang.  1999.  Cytological characterization of potato - Solanum etuberosum somatic hybrids and their backcross progenies by genomic in situ hybridization.  Genome 42(5):987-992.

Dong, Fenggao, Junqi Song, and Jiming Jiang.  1999.  Development of chromosome-specific cytogenetic DNA markers in potatoes.  Am. J. Potato Res. 76(6):368.  (Abstract)

Douches, D.S. and D.L. Maas.  1998.  Comparison of FDR-  and SDR-derived tetraploid progeny from 2x x 4x crosses using haploids of Solanum tuberosum L. that produce mixed modes of 2n eggs.  Theor. Appl. Genet. 97(8):1307-1313.

Ermishin, A.P., and E.V. Voronkova.  1998.  Indicators of  fertility of hybrid progeny of potato secondary dihaploids.  Seriya Biyalagichnykh Navuk 3:45-52.

Estrada, Nelson, R. Pineda, A. Rodriguez, and Sonia Tinjaca.  1999.  Crossability between Solanum stoloniferum and Solanum palustre, two wild potato species.  Am. J. Potato Res. 76(6):368-369.  (Abstract)

Estrada, Nelson and Sonia Tinjaca.  1999.  Crossability between Solanum palustre and Solanum etuberosum, two non-tuber-bearing potato species.  Am. J. Potato Res. 76(6):369.  (Abstract)

Ewing, Elmer E., Ivan Simko, Christine D. Smart, Merideth W. Bonierbale, Eduardo S.G. Mizubuti, Gregory D. May, and William E. Fry.  1999.  An R-gene from Solanum berthaultii for resistance to Phytophthora infestans maps to chromosome 10.  Am. J. Potato Res. 76(6):369.  (Abstract)

Genualdo, G., A. Errico, Z. Tiezzi, and C. Conicella.  1998.  Tubulin and F-actin distribution during microsporogenesis in a 2n pollen producer of Solanum.  Genome 41(5):636-641.

Glass, Jenny Rebecca, K.B. Johnson, and M.L. Powelson.  1999.  Barriers to potato tuber infection by Phytophthora infestans.  Am. J. Potato Res. 76(6):369-370.  (Abstract)

Hanneman, Robert E., Jr.  1999.  Techniques to transfer germplasm from 2X(1EBN) Mexican species to 2X(2EBN) material via hybridization.  Am. J. Potato Res. 76(6):371.  (Abstract)

Hanneman, Robert E., Jr.  1999.  Reproductive biology of the potato.  14^th Triennial Conf. Eur. Assoc. Potato Res. Pp. 14-17.  (Abstract)

Hanneman, R.E., Jr. and M. Ramon.  1999.  Evaluation and pre-breeding with new sources of resistance to Colorado potato beetle and late blight.  Am. J. Potato Res. 76(6):371-372.  (Abstract)

Hanneman, R.E., Jr., M. Ramon, and J.C. Kuhl.  1999.  Potato genetics and enhancement project. pp. 14-21.  K.G. Haynes (ed.). National Potato Germplasm Evaluation and Enhancement report, 1998.  USDA, ARS, Beltsville, Maryland.

Haynes, K.G., D.P. Weingartner, D.S. Douches, C.A. Thill, G. Secor, W.E. Fry, D.H. Lambert, B.J. Christ, and R. Voss.  1999.  Foliar resistance to late blight in potato clones evaluated in national trials in 1998.  Am. J. Potato Res. 76(6):370.  (Abstract)

Helgeson, John P., S. Kristine Naess, James M. Bradeen, Susan M. Wielgus, and Geraldine T. Haberlach.  1999.  Availability of somatic hybrids between potato and wild Solanum species for obtaining new disease resistant breeding lines.  Am. J. Potato Res. 76(6):370.  (Abstract)

Horvath, S., I. Wolf, and Z. Polgar.   1998.  Results and importance of resistance breeding against viruses in Hungary.  In: Breeding research on potatoes. Proceedings of an international symposium, June 23-26, 1998, Gross Lusewitz, Rostock, Germany. (Ed: K. Peter). 4(2):75-80.

Hosaka, K. and R.E. Hanneman, Jr.  1998.  Genetics of self-compatibility in a self-incompatible wild diploid potato species Solanum chacoense.  2. Localization of an S locus inhibitor (Sli) gene on the potato genome using DNA markers.  Euphytica 103(2):265-271.

Hosaka, Kazuyoshi.  1999.  A genetic map of Solanum phureja clone 1.22 constructed using RFLP and RAPD markers.  Am. J. Potato Res. 76(2):97-102.

Jackson, S.A. and R.E. Hanneman, Jr.  1999.  Crossability between cultivated and wild tuber-bearing Solanums.  Euphytica 109:51-67.

Jakuczun, H.  1998.  Diploid breeding of potato for quality traits. In: Breeding research on potatoes. Proceedings of an international symposium, June 23-26, 1998, Gross Lusewitz, Rostock, Germany. (Ed: K. Peter). 4(2):81-82.

Jansky, S.H., S. Austin-Phillips, and C. McCarthy.  1999.  Colorado potato beetle resistance in somatic hybrids of diploid interspecific Solanum clones.  HortScience 34(5):922-927.

Johnson, Alexander, A.T., A. Raymond Miller, and Richard E. Veilleux.  1999.  Agronomic, leptine and fertility analysis of a potato somatic hybrid and first generation progeny.  Am. J. Potato Res. 76(6):373.  (Abstract)

Johnston, S.A. and R.E. Hanneman, Jr.  1999.  The nature of the genetic control of Endosperm Balance Number based on aneuploid analysis of Datura.  Sexual Plant reprod. 12:71-75.

Kardolus, J.P. and N. Bezem.  1998.  The floral abscission zone in Series Acaulia and related taxa of Solanum section Petota.  Canadian J. Bot. 76(8):1424-1432.

Karlsson, B.H. and J.P. Palta.  1999.  Expression of heat-stable and putative dehydrin proteins during nonacclimated and cold-acclimated conditions in several tuber-bearing Solanum species.  J. Am. Soc. Hort. Sci. 124(3):245-251.

Kiru, Stefan and N.I. Vavilov.  1999.  Solanum andigenum Juz. et Buk. as basic material for high starch potato breeding.  Am. J. Potato Research 76(6):375.  (Abstract)

Kowalski, S.P., J.M. Domek, K.L. Deahl, and L.L. Sanford.  1999.  Performance of Colorado potato beetle larvae, Leptinotarsa decemlineata (Say), reared on synthetic diets supplemented with Solanum glycoalkaloids.  Am. J. Potato Res. 76(5):305-312.

Kuhl, J.C., R.E. Hanneman, Jr., and M.J. Havey.  1999.  Resistance to Phytophthora infestans in diploid Solanum species of Mexico and South America.  Am. J. Potato Res. 76(6):376.  (Abstract)

Kuhl, J.C., M. Ramon, R.E. Hanneman, Jr., and M.J. Harvey.  1999.  Evaluation of late-blight resistance in Mexican 2x(1EBN) species.  14^th Triennial Conf. Eur. Assoc. Potato Res. Pp.156-157.  (Abstract)

Laferriere, L.T., J.P. Helgeson, and C. Allen.  1999.  Fertile Solanum tuberosum + S. commersonii somatic hybrids as sources of resistance to bacterial wilt caused by Ralsonia solanacearum.  Theor. Appl. Genet. 98(8):1272-1278.

Laferriere, L.T., C. Allen, and J.P. Helgeson.  1999.  Bacterial wilt resistance from Solanum commersonii: Strain specificity and systemic colonization by Ralstonia solanacearum.  Am. J. Potato Res. 76(6):376.  (Abstract)

Love, S.L.  1999.  Founding clones, major contributing ancestors, and exotic progenitors of prominent North American potato cultivars.  Am. J. Potato Res. 76(5):263-272.

Lozoya-Saldana, Hector and A. Hernandez-Vilchis.  1999.  Three year evaluation of international potato clones for resistance to late blight in the Toluca Valley, Mexico.  Am. J. Potato Res. 76(6):377.  (Abstract)

Lu WenHe, Chen YiLi, Tian XingYa, Wang FengYi, and Qin Xin.  1998.  The potential breeding value of two newly developed 2n pollen producing diploid hybrids in potato.  J. NE Agric. Univ. 5(2):96-103.

Malakar, R. and W.M. Tingey.  1999.  Resistance of Solanum berthaultii foliage to potato tuberworm (Lepidoptera: Gelechiidae).  J. Ec. Ent. 92(2):497-502.

McGrath, J.M. and J.P. Helgeson.  1998.  Differential behavior of Solanum brevidens ribosomal DNA loci in a somatic hybrid and its progeny with potato.  Genome 41(3):435-439.

Mietkiewska, E.  1999.  Interaction between two types of resistance to PVM originating from Solanum gourlayi and  S. megistacrolobum in tetraploid potatoes.  Biuletyn Instytutu Hodowli i Aklimatyzacji Roslin No. 209:125-135.

Murphy, Agnes, Henry DeJong, and Kenneth Proudfoot.  1999.  F87084: A fertile, adapted clone with multiple disease resistances.  Am. J. Potato Res. 76(6):379.  (Abstract)

Naess, S.K., S.M. Wielgus, J.M. Bradeen, G.T. Haberlach, and J.P. Helgeson.  1999.  Introgressing late blight resistance from Solanum bulbocastanum into potato.  Am. J. Potato Res. 76(6):379-380.  (Abstract)

Novy, Richard and Craig Longtine.  1999.  Introgression of virus resistance from Solanum etuberosum to cultivated potato.  Am. J. Potato Res. 76(6):380.  (Abstract)

Oberwalder, B., L. Schilde-Rentschler, B. Ruoss, S. Wittemann, and H. Ninnemann.  1998.  Asymmetric protoplast fusions between wild species and breeding lines of potato -- effect of recipients and genome stability.  Theor. Appl. Genet. 97(8):1347-1354.

Oltmans, Shannon M. and Richard G. Novy.  1999.  Development of cold chipping potato cultivars by the use of wild species.  Am. J. Potato Res. 76(6):380-381.  (Abstract)

Ortiz, R.  1998.  Potato breeding via ploidy manipulations.  Pl. Breed. Reviews 16:15-86.

Paz, M.M. and R.E. Veilleux.  1999.  Influence of culture medium and in vitro conditions on shoot regeneration in Solanum phureja monoploids and fertility of regenerated doubled monoploids.  Plant Breeding 118(1):53-57.

Pelletier, Y., G. Grondin, and P. Maltais.  1999.  Mechanism of resistance to the Colorado potato beetle in wild Solanum species.  J. Ec. Ent. 92(3):708-713.

Peloquin, S.J., L.S. Boiteux, and D. Carputo.  1999.  Meiotic mutants in potato-valuable variants.  Genetics 153:1493-1499.

Perez, F., A. Menendez, P. Dehal, and C.F. Quiros.  1999.  Genomic structural differentiation in Solanum: comparative mapping of the A- and E-genomes.  Theor. Appl. Genet. 98(8):1183-1193.

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.  1999.  Reba: A mid to late season golden nematode resistant variety for use as tablestock or chipstock.  Am. J. Potato Res. 76(1):1-4.

Podgaetskii, A.A.  1997.  Utilizing relatives of cultivated potato for the development of sources of tuber Phytophthora resistance.  Tsitologiya i Genetika 31(5):37-45.

Polgar, Z., S.M. Wielgus, S. Horvath, and J.P. Helgeson.  1999.  DNA analysis of potato + Solanum brevidens somatic hybrid lines.  Euphytica 105(2):103-107.

Reeves, A.F., G.A. Porter, T.M. Work, D.H. Lambert, and A.A. Davis.  1999.  Quaggy Joe: A high-yielding, round, white potato variety for the fresh market.  Am. J. Potato Res. 76(6):331-335.

Reeves, A.F., O.M. Olanya, J.H. Hunter, and J.M. Wells.  1999.  Evaluation of potato varieties and selections for resistance to bacterial soft rot.  Am. J. Potato Res. 76(4):183-189.

Rokka, V.M., A. Tauriainen, J. Laurila, J. Larkka, L. Pietila, M. Seppanen, M. Metzler, and E. Pehu.  1998.  Utilization of wild species Solanum acaule in potato germplasm improvement by somatic hybridization.  In: Breeding research on potatoes.  Proceedings of an international symposium, June 23-26, 1998, Gross Lusewitz, Rostock, Germany. (Ed: K. Peter). 4(2):153-154.

Rokka, V.M., C.A. Ishimaru, N.L.V. Lapitan, and E. Pehu.  1998.  Production of androgenic dihaploid lines of the disomic tetraploid potato species Solanum acaule ssp. acaule.  Plant Cell Reports 18(1/2):89-93.

Ronning, C.M., J.R. Stommel, S.P. Kowalski, L.L. Sanford, R.S. Kobayashi, and O. Pineada.  1999.  Identification of molecular markers associated with leptine production in a population of Solanum chacoense Bitter.  Theor. Appl. Genet. 98(1):39-46.

Schwarzfischer, A., J. Schwarzfischer, and L. Hepting.  1998.  Resistance and quality breeding with somatic hybridization.  In: Breeding research on potatoes. Proceedings of an international symposium, June 23-26, 1998, Gross Lusewitz, Rostock, Germany. (Ed: K. Peter). 4(2):165-167.

Sebastiano, A., D. Carputo, F. Filotico, and A. Barone.  1998.  Monitoring gene flow introgression from S. commersonii to S. tuberosum through molecular markers. In: Breeding research on potatoes.  Proceedings of an international symposium, June 23-26, 1998, Gross Lusewitz, Rostock, Germany. (Ed: K. Peter). 4(2):173-174.

Sieczka, Maria T., Charles R. Brown, Edyta Gawronska, Kazimierz M. Swiezynski, Hanna Zarzycka, and Ewa Zimnoch-Guzowska.  1999.  Identification of potatoes resistant to new strains of late blight (Phytophthora infestans).  Am. J. Potato Res. 76(6):384.  (Abstract)

Sorri, V.A., K.N. Watanabe, and J.P.T. Valkonen.  1999.  Predicted kinase-3a motif of a resistance gene analogue as a unique marker for virus resistance.  Theor. Appl. Genet. 99(1/2):164-170.

Souza-Dias, J.A.C. de, P. Russo, L. Miller, and S.A. Slack.  1999.  Comparison of nucleotide sequences from three potato leafroll virus (PLRV) isolates collected in Brazil.  Am. J. Potato Res. 76(1):17-24.

Takacs, A., G. Kazinczi, J. Horvath, and D. Pribek.  1998.  Reaction of wild Solanum species to the tuber necrosis strain of potato Y potyvirus (PVY^NTN).  Novenytermeles 47(1):1-4.

Tek, Ahmet L., John P. Helgeson, and Jiming Jiang.  1999.  Molecular cytogenetic characterization of Solanum brevidens chromatin introgressed into potato.  Am. J. Potato Res. 76(6):385.  (Abstract)

Thieme, T. and R. Thieme.  1998.  Evaluation of plant resistance to potato virus Y (PVY) in a wild species and potato breeding clones of the genus Solanum. In: Breeding research on potatoes. Proceedings of an international symposium, June 23-26, 1998, Gross Lusewitz, Rostock, Germany. (Ed: K. Peter). 4(2):192-193.

Thieme, T. and R. Thieme.  1998.  Evaluation of resistance to potato virus Y (PVY) in wild species and potato breeding clones of the genus Solanum.  Aspects of Appl. Biology 52:355-359.

Thill, Christian A.  1999.  University of Minnesota potato breeding and germplasm development.  Proc. National Potato Germplasm Evaluation and Enhancement Report.  USDA/ARS.

Thill, Christian A. and S.J. Peloquin.  1999.  The identification of superior parents having 25% Solanum tarijense and used to develop cold-chipping progeny.  Eur. Assoc. Pot. Res. 14^th Triennial Conf.  (Abstract)

Thill, Christian A., E.B. Radcliffe, and D.W. Ragsdale.  1999.  Breeding for potato leafhopper resistance using wild Solanum species.  Am. J. Potato Res. 76(6):385.  (Abstract)

Varrieur, John M., Rebecca J. Cutright, and Richard E. Veilleux.  1999.  Selection pressures inherent in the monoploid derivation-mechanisms, androgenesis and gynogenesis.  Am. J. Potato Res. 76(6):386.  (Abstract)

Veilleux, R.E. and A.R. Miller.  1998.  Hybrid breakdown in the F₁ between Solanum chacoense and  S. phureja and gene transfer for leptine biosynthesis.  J. Am. Soc. Hort. Sci. 123(5):854-858.

Voort, J.N.A.M.R. van der, G.J.W. Janssen, H. Overmars, P.M. van Zandvoort, A. van Norel, O.E. Scholten, R. Janssen, and J. Bakker.  1999.  Development of a PCR-based selection assay for root-knot nematode resistance (Rmcl) by a comparative analysis of the Solanum bulbocastanum and S. tuberosum genome.  Euphytica 106(2):187-195.

Wang FengYi, Chen YiLi, Tian XingYa, Lu WenHe, and Qin Xin.  1998.  The improvement and utilization of Neo-Tuberosum clones.  J. NE Agric. Univ. 5(2):111-116.

Watanabe, J.A., M. Orrillo, and K.N. Watanabe.  1999.  Frequency of potato genotypes with multiple quantitative pest resistance traits in 4x x 2x crosses.  Breeding Science 49(2):53-61.

Yamada, T., K. Hosaka, N. Kaide, K. Nakagawa, S. Misoo, and O. Kamijima.  1998.  Cytological and molecular characterization of BC₁ progeny from two somatic hybrids between dihaploid Solanum acaule and tetraploid S. tuberosum.  Genome 41(6):743-750.

Yang LiMei, E. Jacobsen, M.S. Ramanna, M. Bergervoet, and D.J. Huigen.  1998.  Protoplast fusion and detection between genera and species in Solanum.  Advances in Hort. 2:412-416.

Yencho, G.C., S.P. Kowalski, R.S. Kobayashi, S.L. Sinden, M.W. Bonierbale, and K.L. Deahl.  1998.  QTL mapping of foliar glycoalkaloid aglycones in Solanum tuberosum x  S. berthaultii potato progenies: quantitative variation and plant secondary metabolism.  Theor. Appl. Genet. 97(4):563-574.

Yencho, G.C., S.P. Kowalski, G.G. Kennedy, and L.L. Sanford.  1999.  Leptine glycoalkaloids and Colorado potato beetle resistance in F2 Solanum tuberosum x S. chacoense progenies.  Am. J. Potato Res. 76(6):387-388.  (Abstract)

Zimnoch-Guzowska, E., R. Lebecka, and J. Pietrak.  1999.  Soft rot and blackleg reactions in diploid potato hybrids inoculated with Erwinia spp.  Am. J. Potato Res. 76(4):199-207.

Zlesak, David C. and C.A. Thill.  1999.  The identification of late blight resistance in 1, 2, and 4EBN wild Solanum species for use in breeding.  Am. J. Potato Res. 76(6):388.  (Abstract)

C.        Theses Reporting Research with NRSP-6 Stocks

del Rio, Alfonso H.  1999.  Use of RAPD markers to assess genetic diversity in two model species at the U.S. potato genebank.  Ph.D. Thesis.  University of Wisconsin, Madison, WI.  173 pp.

Raker, C.M.  1999.  An examination of the Solanum tuberosum subspecies tuberosum and subspecies andigena using microsatellite markers.  M.S. Thesis.  University of Wisconsin, Madison, WI.  123 pp.

Vega Semorile, Sandra E.  1999.  Understanding mechanisms of potato cold hardiness by merging physiological, genetic and molecular approaches.  Ph.D. Thesis. University of Wisconsin, Madison, WI.  177 pp.   

7.  APPROVED

            C. R. Brown, Chairman, Technical Committee              Date

            R. L. Lower, Lead Administrative Advisor                     Date