Location: Vegetable Crops Research
2023 Annual Report
Objectives
Objective 1: Conduct research to develop genetic resource maintenance, evaluation, or characterization methods and, in alignment with the overall NPGS Plan, apply them to priority potato genetic resources to avoid backlogs in genetic resource and information management.
Objective 2: Acquire, distribute, and maintain the safety, genetic integrity, health, and viability of priority potato genetic resources and associated descriptive information.
Approach
Conduct research to develop genetic resource maintenance, evaluation, or characterization methods and, in alignment with the overall NPGS Plan, apply them to priority potato genetic resources to avoid backlogs in genetic resource and information management. Make core subsets from species with many populations, or complete a related study of status and dynamics of genetic diversity in the genebank. Perform one in-house phenotypic evaluation, ideally for a new valuable trait, or for common traits from a more breeding-friendly germplasm source. Perform joint research projects with specialist collaborators to identify valuable germplasm, including making of custom samples, propagules and/or research populations. Identify in situ population locations and study valuable germplasm at sites in southwest U.S. Perform greenhouse botanical seed multiplication. Annually assess whole seed collection in terms of seed numbers and germination. Process, label, organize, and store multiplied seeds at -20C. Rely on longstanding methods to secure new seeds (at least 200 accessions per year) in storage in a way that results in maximum long-term viability. Transfer in vitro clonal collection stocks to fresh medium as needed to maintain viability. Use longstanding methods to keep the 1500 clonal collection alive and continuously available for distribution. Maintain optimal virus test schedule and records for all seeds and clones. Assess germination of all seedlots within a 5-year interval which equals at least 1200 accessions per year. Distribute data, advice, information, and germplasm efficiently to cooperators.
Progress Report
This is the first report for this new project which continues research from the previous project, 5090-21000-066-000D, Management of Genetic Resources and Associated Information in the U. S. Potato Genebank. lease see the report for the previous project for additional information.
Objective 1 - Research for characterization and technical use of the germplasm: 1) progress was made toward producing a core collection of 62 diploid cultivated potato lines selected for Late blight resistance, 2) stocks with novel introgression of Solanum jamesii into cultivated forms of potato were planted for field and greenhouse evaluation, 3) progress was made on detecting artifacts that confuse conclusions when bulking to capture DNA diversity of a population, 4) progress was made on testing how well backcrossing works for converting rare single-genotype accessions to botanical seed form, and 5) progress was made in synthesizing and testing populations with resistance to Dickeya tuber rot, Zebra chip disease, and drought tolernace.
Objective 2 - Service for maintaining and improving germplasm services for the nation’s researchers and breeders: 1) progress was made in converting a duplicate set of the clonal tissue culture collection to microtubers, 2) Polymerase Chain Reaction - based testing for Potato Spindle Tuber Viroid was fully validated for seedlots, and a program for retesting all germplasm was initiated, 3) greenhouse grow-outs validated high germination and vigor of nearly all genebank seedlots, and 4) adaptations of greenhouse and screenhouse were made to test feasibility of summer seed increases to expand genebank’s seed multiplication capacity.
Accomplishments
1. Acquisition of valuable breeding stocks with drought, frost and disease tolerance from diverse regions. ARS researchers at Madison, Wisconsin, and their collaborators evaluated and imported a new frost and drought tolerant variety, Wiñay, from Peru. They evaluated a set of seedlots reputed to have potent resistance to Late blight, the worst fungal disease of potato foliage. They evaluated seedlots of a species reputed to have potent resistance to Zebra chip, a very serious disease of potato tubers. The U.S. Potato Genebank (USPG) has now identified, multiplied, and preserved selections that have extreme value for each of these traits and made them available to clients. The potato is the most important vegetable crop in the United States and world. Frosts early and late in the season can reduce yield and quality of the crop. Drought stress tolerance can reduce losses if rain becomes less reliable and irrigation more expensive. Natural Late blight and Zebra chip resistance are economical alternatives to pesticide application. Now users of USPG germplasm will have potent new tools to protect it from new diseases; and stresses like heat, drought, disease and frost, all which have increasing importance due to climate change.
