1a. Objectives (from AD-416)
Strategically expand the genetic diversity in genebank collections and improve associated information for priority vegetable, sorghum, peanut, subtropical/tropical legume, and warm-season grass genetic resources. Conserve and regenerate priority vegetable, sorghum, peanut, subtropical/tropical legume, new crop, and warm-season grass genetic resources efficiently and effectively, and distribute pathogen-tested samples and associated information worldwide. Strategically characterize (“genotype”) and evaluate (“phenotype”) priority vegetable, sorghum, peanut, subtropical/tropical legume, and warm-season grass genetic resources for molecular markers, morphological descriptors, and key agronomic or horticultural traits such as biochemical content and product quality. Conserve, regenerate, and distribute germplasm of specialty crops, current or potential bioenergy crops (e.g., sweet sorghum, switch grass, and Miscanthus), and new genetic stocks generated by genomic research (e.g., assocition mapping projects) with sorghum and other crops.
1b. Approach (from AD-416)
Acquire samples of native warm-season grasses, bioenergy crops, subtropical legumes, Ipomoea species, chile pepper, and annual clovers to fill current gaps in NPGS collections. Survey existing holdings of sorghum genetic stocks, identify material that would fill gaps in NPGS collections, and begin acquiring and characterizing them. Conserve and distribute genomic research genetic stocks including association mapping populations of sorghum and other crops. Regenerate, conserve, and distribute more than 88,000 accessions of specialty crops, bioenergy crops, and other priority genetic resources and associated information. Increase the number of sweetpotato and warm-season grass clonal accessions maintained in tissue culture. Increase to 95 percent the proportion of the collection backed up at second sites. Develop superior regeneration methods for seed and clonally-propagated crops. Assay stored genetic resources for vigor, viability, and health. Distribute on request accessions and information that meet the specific needs of researchers and breeders. Develop and apply new genetic markers for phylogenetic and genetic diversity analyses of priority crops. Update and apply phenotypic descriptors for vegetables, peanuts, warm-season grasses, and subtropical/tropical legumes. Develop, enhance, and/or apply high performance liquid chromatography (HPLC) procedures for analyzing variation in flavonoids, antioxidants, capsaicin, and other key phytochemicals in accessions. Incorporate characterization, phenotypic, and biochemical data into GRIN and/or other databases.
3. Progress Report
A total of 90,942 accessions of 1,534 plant species were maintained in the Griffin plant genetic resources collection. Over 87.7% of accessions were available for distribution to users and over 97.1% were backed up for security at a second location. Bulk seed samples for 66,995 accessions were maintained at -18 C for long-term storage with seed of the remaining accessions stored at 4 C. A total of 28,308 seed and clonal accessions in 925 separate orders were distributed upon request to scientists and educators in 49 U.S. states and 47 foreign countries. Acquisitions made to the collection included 143 sorghum, 144 warm-season grass, 19 vegetable and 2 other accessions. A plant collection trip was conducted in Alabama, Florida, Georgia, and South Carolina for naturalized Sorghum halepense germplasm that is in demand for sorghum gene flow studies. Seed regenerations and characterization were conducted on 299 peanut, 131 cowpea, 46 warm-season grass, 60 pepper, 361 legume, new, and misc. crop, 91 annual clover, and 30 other vegetable accessions. Over 300 pepper accessions were grown in the field for regeneration, characterization and recording of digital images. Digital images of cowpea, sorghum, cucurbit, and watermelon accessions, and pepper capsaicin content, peanut core selection, sorghum, and sweet sorghum data were added to the Germplasm Resources Information Network (GRIN). Long-term maintenance of 241 wild peanut and 458 warm-season grass accessions was continued in the greenhouse. Over 30 warm-season grass accessions and 712 sweetpotato accessions were maintained in tissue culture with eight replications of each sweetpotato clone. Germination testing has been completed for 69,556 accessions (over 77% of collection) since 2002. In cooperation with vegetable industry plant pathologists, differential sets of four vegetable crops are being established and distributed to researchers for identification of disease races. Fatty acid content was determined for the entire U.S. castor bean (over 1,000 accessions) and sesame (over 1,200 accessions) collections and 98 okra accessions. Over 660 castor accessions were genotyped with 15 Simple Sequence Repeats (SSR) markers for further genetic classification. A population of over 1,900 mutant watermelon seeds were developed for a mutant Targeting Induced Local Lesions in Genomes (TILLING) study with ARS cooperators in Charleston, SC. Ploidy level was determined for the entire St. Augustine and seashore paspalum grass collections. Photoperiod-sensitive Neonotonia, Teramnus, and annual clover accessions were successfully regenerated in the greenhouse. A total of 92 peanut accessions were successfully evaluated under quarantine and disease-free seed was produced. In association with Kansas State University scientists, 1,000 biomass sorghum accessions will be evaluated for plant morphology, biochemical composition, and genotype.