2013 Annual Report
1a.Objectives (from AD-416):
Objective 1: Develop and apply new methods for managing potato genetic resources which improve genebank operating efficiency and effectiveness, and which enable pathogen-tested materials and associated information to be distributed worldwide.
Objective 2: Maintain, regenerate, back-up, monitor, and distribute genetic resources and associated information for potato and related wild species.
Objective 3: Evaluate and characterize potato genetic resources for priority genetic and horticultural traits. Apply knowledge of patterns of genetic divergence and diversity in potato to strategically expand the collection.
1b.Approach (from AD-416):
We will systematically test potential improvements in germplasm preservation and handling techniques through various enhancers of seed germination, flowering and botanical seed yield, pollen viability, and improved methods of plant fertilization. We will acquire selected germplasm for the genebank from within the USA and abroad after consultation with state and federal advisory committees. We will classify germplasm with morphological and DNA marker assessments. We will preserve germplasm by performing seed increase of at least 200 accessions per year yielding >10,000 seeds on the populations with lowest seed numbers and germination, testing for disease, and backup in the national base collection at Ft. Collins, CO. We will distribute germplasm free of charge to federal, state, corporate and private clients in the US and abroad. We will evaluate genebank germplasm through partnerships with ARS, state, industry, and foreign scientists with expertise in various specialties of potato research. We also aim to continue to discover and describe simple physiological and genetic traits in-house. We will particularly seek evaluation projects studying nutritional potential in exotic germplasm. Evaluation of the patterns of genetic diversity in the genebank will be done using DNA markers. As in the past, the empirical evidence gained will be used to modify genebank techniques so the best practices are in place for maximizing the acquisition, preservation, and evaluation of genetic diversity in the genebank.
Availability of potato germplasm is important to the progress of basic research and breeding. During May - June 2013, the genebank at Sturgeon Bay, Wisconsin in cooperation with worldwide collaborators, continued filling this need by distributing (free of charge), viable and disease free stocks to all those who requested them, which fulfills the project's Objective 2 to maintain and distribute germplasm. We also evaluated and documented valuable traits as mandated by Objective 3. Orders were filled within one week of receipt. Summer field plantings of nearly 2000 plots were completed, including plots to verify that seed multiplication efforts last year resulted in offspring seedlots that matched their parents. Four large screenhouses with research stocks for various traits were planted. A summer seed increase of genebank stocks with low germination or few seeds was initiated. A germination experiment was started to compare long-term viability of seeds that had been produced 25 years ago on parents without extra fertilizer versus seeds produced on the same parents with extra fertilizer. We acquired funds for, and planned a new germplasm collecting expedition to the southwest United States. A new program was initiated with a Canadian cooperator to look for even better somaclonal variants in genebank stocks high in antioxidants and folate. With cooperators in Peru, stocks with very favorable response to fertilizer calcium and exceptional frost tolerance were identified at their June harvest in Huancayo and Puno regions. The above are all specific steps in developing new methods that will forward the productive use of potato germplasm by developing new technologies (Objective.
1)and evaluating and expanding the breadth of knowledge and physical germplasm available (Objective 3).
Floral mutants can be useful tools for understanding sexual reproduction. The new floral mutant ARS researchers at Sturgeon Bay, WI discovered in the wild potato Solanum stoloniferum form fendleri has been named "Matryoshka." It was found to have unique expressions of male and female sterility, as well as producing seedless berries. This could result in progress toward more complete understanding and control of flowering and fruiting. That would be very useful in potato, and such knowledge might transfer to the closely-related fruit-crops tomato, pepper, and eggplant. This is important to US consumers who eat a lot of these vegetables, since they stand to benefit from research tools that improve those crops.
Confirmed success in visual categorization within species. When the genebank has many populations of a given species, it would be useful to be able to group them very easily to guide prioritization for evaluation and preservation. New evidence gathered by ARS scientists at Sturgeon Bay, WI confirmed that quick visual classification is repeatable, and matches genetic relatedness according to deoxyribonucleic acid (DNA) markers. Documenting and characterizing these classes will help germplasm users understand and use the variation expressed within species. Since the whole point of having and studying genetic resources is to find ways to manage genetic variation pursuant to improvement of the crop, this work should eventually make improving the potato crop more efficient. That better potato crop will provide an improved food for the farmer and consumer.
New potato anti-cancer information. Diverse stocks kept at the United States Potato Genebank, Sturgeon Bay, Wisconsin, hold promise for improving anti-cancer components of potato. One such component, tomatine, exists in very high levels in certain exotic potato species. For the first time, ARS researchers at Sturgeon Bay, WI identified true hybrids with cultivated forms that could be used to bring tomatine into the potato crop. Transformation of the potato crop to contain an anti-cancer compound, could increase United States citizens' health and reduce their healthcare costs.