Brief Summary of Minutes of Annual Meeting

Steven R. Alm (stevealm@uri.edu) - University of Rhode Island;
Paul Backman (pbackman@psu.edu) - Pennsylvania Agricultural Experiment Station;
Mark J. Carroll (mc92@umail.umd.edu) - University of Maryland;
J. Marshall Clark (jclark@ent.umass.edu) - University of Massachusetts;
Bruce B. Clarke (clarke@aesop.rutgers.edu) - Rutgers University;
Richard S. Cowles (rcowles@caes.state.ct.us) - Connecticut Agricultural Experiment Station;
J. Scott Ebdon (sebdon@pssci.umass.edu) - University of Massachusetts;
Steven Fales;
Karl Guillard (karl.guillard@uconn.edu) - University of Connecticut;
Richard J. Hull (rhu6441@postoffice.uri.edu) - University of Rhode Island;
Noel Jackson;
Peter J. Landschoot (pj11@psu.edu) - The Pennsylvania State University;
Pim Larsson-Kovach (il11@cornell.edu) - Cornell University;
James Lin - USEPA;
Bill Meyer (wmeyer@aesop.rutgers.edu) - Rutgers University;
Kevin Morris - NTEP;
Bridget Ruemmele (bridgetr@uri.edu) - University of Rhode Island;
Mike Sullivan (senmike@uriacc.uri.edu) - University of Rhode Island;
Patricia Vittum (pvittum@ent.umass.edu) - University of Massachusetts

Regional potato project NE-184 has three major objectives for linking research and extension activities of this multidisiciplinary and multi-institutional workgroup which encompasses the entire eastern US and Canadian potato industry. The goal of this project is to identify needs of the potato industry, as well as those of the environment and especially the consumer, and develop solutions to those needs. It should be noted that the seed, tablestock and processing markets are all impacted by segments of this programs activities.

Objective 1. Determine the heritability of traits of economic importance and improve the genetic base of tetraploid potatoes.

Objective 1.a. Determine the heritability of internal heat necrosis in chipping lines and any relationship between high specific gravity and susceptibility to heat necrosis.

A collaborative internal heat necrosis study has been underway to develop new, high gravity cultivars free from internal heat necrosis (IHN), a chronic problem in tubers grown in high summer temperature areas of the mid-Atlantic region. For the heat necrosis study, eighty-eight 4x-2x hybrids provided by Dr. Haynes, USDA-ARS-BARC were evaluated at locations with high temperature growing conditions. Trials were planted in NC by Dr. Yencho (NCSU), NJ by Dr. Henninger (Rutgers) and VA by Dr. Sterrett (VA Tech). Trials were harvested and tubers were sized and weighed, specific gravity measured and tubers cut open and rated for IHN. The experiment had good levels of IHN present in some clones and none in others, indicating that we had a good range of values for future analyses. An abstract for poster presentation summarizing the results of the 1999 season in NC, NJ and VA has been submitted for presentation at the 2001 Annual Meeting of the Potato Association of America. Another set of 4x-2x hybrids is being increased for testing in 2002 at these same locations.

Objective 1.b. Determine the inheritance of long-term storage processing ability in diploid potatoes and improve the genetic base for this trait.

Seedlings from crosses made between haploid-species (can. and phu.) hybrids obtained from Dr. Hannemans program and the Beltsville S. phureja-S. stenotomum population were grown in 12-hill plots in 2000 and are in the process of being evaluated for their chipping ability this winter.

Objective 1.c. Improve the genetic base of yellow-flesh potatoes.

Work continues on identifying the carotenoid composition of yellow-fleshed diploid clones. These clones were also crossed with tetraploid and derived tetraploid clones to further enhance the carotenoid composition of potatoes and the first progeny will be evaluated in 2001. Preliminary results suggest that the enhancement of the tetraploid germplasm base with these diploids greatly improves the culinary quality.

Objective 1.d. Improve the genetic base of red-skinned potatoes.

A 4x-2x red-skinned hybrid with double layer of red skin has been identified by Haynes (USDA) and is being utilized as a parent in the crossing program. Additional crosses among 4x-2x hybrids and tetraploid S. tuberosum continue to be made.

Objective 1.e. Improve the genetic base of resistance to late blight.

Crosses between selections from the International Potato Center with good horizontal resistance to late blight and our advanced germplasm were planted in the greenhouse this fall. Diploid populations segregating for late blight resistance were produced and maintained for the molecular work at Penn State and the USDA. Hybridizations between wild species hybrids with late blight resistance and our adapted PHU-STN population were made last winter. Seeds will be planted in fall 2001.

Objective 1.f. Improve the genetic base of resistance to early blight.

General combining ability was found among 4x-2x (Tbr x PHU-STN) hybrids from the early blight resistant population of the USDA-ARS-BARC. Specific combining ability was not important. (Manuscript has been prepared for submission to Plant Breeding).

At Penn State (Dr. Christ) a diploid hybrid Solanum phureja X S. stenotomum F1 population and the two parentals were screened for early and late blight resistance in two separate experiments. There were significant differences among the F1 clones for either early or late blight. The distribution among the clones for early blight severity based on area under disease progress curve values (AUDPC) followed a normal distribution. However, the distribution among the clones for late blight AUDPC was skewed. It appears that already, we have improved late blight resistance in this population when compared to the parental population.

Objective 1.g. Utilize concurrent early-generation selection at diverse environmental locations to enhance selection of lines with abroad adaptation.

Dr. Yencho (NCSU) and Dr. Haynes (USDA) initiated this project in 1998. Each year 5000-7000 seed tubers are planted in duplicate in NC and ME. Crosses are made by Dr. Haynes and half of the true seed resulting from the crosses (representing a wide genetic base) are sent to NC where it is planted and used to produce two seed tubers- one for NC and the other for the USDA/ARS BARC Chapman Farm in ME. During the 2000 season, 4,469 duplicate single hill plantings were established in NC and ME. From this planting, 132 single-hill selections (57 in NC and 79 in ME with 4 being selected at both sites) were made. 59 clones were selected (29 in NC and 39 in ME with 9 being selected at both sites from the 258 second year selections remaining from our 1999 singles, and 17 selections (10 in NC and 10 in ME with 3 selected at both sites from the 68 third year selections remaining from our singles in 1998. The 17 clones remaining from the first cycle of selection will be evaluated in 2001 in replicated yield trials in NC, NJ and VA, while the remaining first, second and third year selections will be evaluated in NC and ME.


A project similar to that above was initiated in 1999 by Dr. Yencho and Dr. Reeves, Univ. of Maine. In 1999, Dr. Reeves saved enough seed from each of his 244 single-hill selections to plant duplicate 4-hill plots in ME and NC during 2000. The 244 selections were planted in NC and Dr. Yencho selected 7 of these for further evaluation in 2001 as 20-hill plots. As in the previous year, selections made in NC will be saved in ME and evaluated in both environments. As above, each of these selections has the potential to produce a new variety better adapted to a wide region, but they need to be further evaluated in larger plots and replicated trials over multiple years.

Objective 2. Evaluate pest and disease resistant, early-maturing, long-dormancy varieties for fresh market and/or processing from cold storage.

Objectives 1.e. and 1.f. above also address Objective 2 to develop varieties resistant to late blight and early blight.


At Penn State twenty-two cultivars and lines were evaluated for early blight, late blight and powdery scab disease reaction in separate trials by Dr. Christ. Early blight severity ranged from 11% to 98%. Five lines had less than 25%: Eva, Kennebec, Russet Burbank, AF1758-7 and Keuka Gold. Late blight never progressed beyond spreader rows, therefore no data was recorded. Powdery scab incidence was high and ranged from 4% to 84%. Four lines had less than 20%: Russet Norkotah #3117, Snowden, NY112 and Russet Burbank. In yield trials, NY112, NY 120 and AF1437-1 had yields greater than Atlantic. Chip color of NY112 and NY120 were equal or better than Snowden across all storage regimes.


Fifteen potato clones consisting of nine advanced breeding lines (AF1437-1, AF1569-2, AF1615-1, AF875-15, B0178-34, B056-8, B0564-9, B0766-3, B9922-11) and six commercial varieties (Atlantic, Cherry Red, Snowden, SuperiorAG, SuperiorUS, and Yukon Gold) were evaluated for their susceptibility to Rhizoctonia disease under field conditions in NC. The incidence of Rhizoctonia disease (expressed as the percentage of infected stems) ranged from 31-70%. The fungus reduced the number of emerged stems from 0-80% depending on the potato clone and assessment date. Although differences in emergence and disease were observed, these differences were not statistically significant (P=0.05). Also, when compared to the noninoculated control, no differences in total and marketable yield were observed. In addition 12 Solanum have also been included in the hopes of identifying new sources of resistance to Rhizoctonia.



The Cornell breeding program has golden nematode resistance as its highest priority, all selected clones have resistance to Ro1. New York Extension trials in 2000 had 14 named and 54 numbered entries with GN resistance. The latest variety releases, which were tested in NE-184, were Eva and Keuka Gold. Both produce very good yields of attractive tubers over many locations.

Objective 3. Identify and quantify significant climate and cultural effects on the performance of potato selections.


Replicated and observational trials were conducted by all participating locations to determine genotypes best adapted for their growing conditions and markets. Data was collected and evaluated using guidelines established by the NE-184 technical workgroup. All cooperators include standard varieties and breeder choices to maximize our ability to make performance evaluations and comparisons over years and locations. This data is presented in state trial reports, the NE-184 annual report and the USDA Germplasm report, and provided for extensive discussion on clonal performance when deciding which clones to test in the NE-184 project, as well as providing feedback to our three breeders. Various statistical analyses have been conducted on this combined dataset, such as the AMMI model (Ag. Canada-Dr. Tai and Cornell-Dr. Halseth), to help evaluate clonal adaptation-stability, seasonal variation, and trial site characteristics. Cultural practice experiments on seedpiece weight, spacing and fungicide treatments, nitrogen rates, herbicide materials, tuber bruising, storage temperature and utilization (baking, boiling, chip and French fry) quality were conducted during the 2000 season. It is important to develop variety profiles and optimal cultural practices to help identify promising clones and to speed their successful adoption by the potato industry. Growers were provided with seed of the most advanced lines for commercial scale testing in typical growing conditions. Taste panels were conducted on selections to determine culinary acceptance. Industry involvement and consumer input are important to provide a reality check on evaluations and also to get more active participation.

Future Plans:

Project NE-184 plans for 2001 include continuing research on its three objectives. Development of varieties with multiple resistances for disease, insect, nematode and stress problems will be a priority. Clones with longer tuber dormancy and the ability to process out of colder temperatures will reduce dependency on chemical sprout inhibitors. Tubers that resist bruising will enhance processing efficiency and provide much better tablestock quality. Optimal cultural practices for new selections will be developed to help the industry more quickly and successfully adopt them while reducing chemical inputs and hence reduce risk to the environment. Depending upon the region, chip, French fry or novelty tablestock clones will be developed to better serve market needs. We also plan to conduct larger scale (1 to 3 acre) on-farm trials with advanced Cornell, University of Maine and USDA clones.

Brodie, B.B., M. Scurrah, and R.L. Plaisted. 2000. Release of germplasm resistant to multiple races of potato cyst nematodes. Amer. J. Potato Res. 77:207-209.

Christ, B.J. 2000. Severity of early blight on potato cultivars and breeding lines, 1998. Biological and Cultural Tests for Control of Plant Diseases 15:105.

Christ, B.J. 2000. Severity of powdery scab on potato cultivars and breeding lines, 1998. Biological and Cultural Tests for Control of Plant Diseases 15:115.

Christ, B.J. 2000. Severity of early and late blight on potato cultivars and breeding lines, 1998. Biological and Cultural Tests for Control of Plant Diseases 15:112.

Christ, B.J. 2000. Severity of powdery scab on potato cultivars and breeding lines, 1999. Biological and Cultural Tests for Control of Plant Diseases 15:116.

Goth, R.W. and K.G. Haynes. 2000. Evaluation of potato clones for severity of Verticillium wilt, yield and specific gravity in Maine. Amer. J. Potato Res. 77:89-94.

Halseth, D.E., W.L. Hymes, 2000. Upstate New York potato variety trials  1999. 70th National Potato Germplasm Evaluation and Enhancement Report, 1999. K.G. Haynes, editor. 70:In Press

Halseth, D.E., W.L. Hymes and R.L. MacLaury. 2000. Upstate New York potato variety trials and cultural practice experiments. Fruit and Vegetable Science Report 84  Cornell University, 46pp.

Haynes, K.G. 2000. Inheritance of yellow-flesh intensity in diploid potatoes. J. Amer. Soc. Hort. Sci. 125:63-65.

Henninger, M.R. 2000. White Potato Research Report  Summary of Varietial and Cultural Studies. Rutgers Cooperative Extension Publication.

Henninger, M.R., S.B. Sterrett and K.G. Haynes. 2000. Broad-sense heritability and stability of internal heat necrosis and specific gravity in tetraploid potatoes. Crop Sci. 40:977-984.

Porter, G.A., J.A. Sission and B. MacFarline. 2000. Maine potato variety trials  1999. 70th National Potato Germplasm Evaluation and Enhancement Report, 1999. K.G. Haynes, editor. 70:In Press

Porter, G.A., P.C. Ocaya, J.A. Sission, B. MacFarline and P. Wardwell. 2000. Maine potato variety trials  2000. UM Dept. of Plant, Soil & Env. Sciences Mimeo 2000-02.

Porter, G.A., J.A. Sission, P.C. Ocaya, B. MacFarline and P. Wardwell. 2000. Screening of potato varieties and breeding lines for sensitivity to postemergence metribuzin and rimsulfuron, 2000 growing season. UM Dept. of Plant, Soil & Env. Sciences Mimeo 2000-02.

Sterrett, S.B. and C.P. Savage, Jr. 2000. Virginia. 70th National Potato Germplasm Evaluation and Enhancement Report, 1999. K.G. Haynes, editor. 70:In Press

Yencho, G.C., S.P. Kowalski, G.G. Kennedy and L.L. Sanford. 2000. Segregation of leptine glycoalkaloids and resistance to Colorado potato beetle (Leptinotarsa decemlineata Say) in F2 Solanum tuberosum (4x) X S. chacoense (4x) potato progenies. American J. Potato Research 77:167-178.

Zhang, R., and B.J. Christ. 2000. Severity of early blight on potato cultivars and breeding lines, 1999. Biological and Cultural Tests for Control of Plant Diseases 15:106.