Location: Soybean and Nitrogen Fixation Research
Project Number: 6070-21220-068-00-D
Project Type: In-House Appropriated
Start Date: May 16, 2013
End Date: May 15, 2018
1. Discover novel genes, alleles, or QTL in soybean for improved yield-potential, determine their inheritance and genomic locations, use marker-assisted approaches to transfer to adapted backgrounds, and release improved germplasm. 1.A. Identify desirable genetic diversity for seed yield in exotic Asian cultivars. 1.B. Determine the usefulness of F2 heterosis in evaluating exotic Asian soybean germplasm as sources of yield-enhancing alleles. 1.C. Identify desirable genetic diversity for improved seed yield in wild soybean. 1.D. Identify novel allele variants associated with heterosis and increased sink strength in wild soybean using genomic approaches. 1.E. Identify high protein QTL that break the typical negative correlation between high-protein seed content and low seed yield in soybean. 2. Discover novel genes, alleles, or QTL in soybean for seed composition and resistance to seed borne pathogens or other biotic pests, determine their inheritance, verify genomic locations, use marker-assisted approaches to transfer to adapted backgrounds, and release improved germplasm. 2.A. Introgress identified genes for improved seed composition into elite soybean breeding lines. 2.B. Identify novel phenotypes for seed composition traits; map and identify novel genes/QTL. 2.C. Assess the impact of seed composition genes on agronomic traits and disease susceptibility. 2.D. Identify defense genes and defense gene expression patterns in seeds that will differentiate resistant from susceptible soybean genotypes with respect to seed infection by C. kikuchii, the causal agent of purple seed stain (PSS) and P. longicolla, the causal agent of Phomopsis seed decay (PSD). 2.E. Assess the extent to which elevated seed oleate content affects seed colonization by the seed pathogens, C. kikuchii and P. longicolla in high oleic acid genotypes. 2.F. Determine if immunogenic epitopes identified in pigs and dogs are common to other species. 3. Discover novel genes, alleles, or QTL in soybean for tolerance to drought and other environmental stresses, determine their inheritance and verify genomic locations, transfer to adapted backgrounds, and release improved germplasm. 3.A. Identify desirable genetic diversity for drought tolerance in exotic soybean accessions preserved in the USDA Soybean Germplasm Collection. 3.B. Identify desirable genetic diversity for slow wilting in rare breeding stock from applied U.S. breeding programs. 3.C. Determine the impact of a ‘deep rooting trait’ on slow wilting and seed yield during drought. 3.D. Novel phenotypes for stress tolerance exist in the wild soybean and novel alleles/ genes identified in wild soybean important for stress resistance can be introgressed into cultivated soybean.
This is a multidisciplinary program which has the expressed purpose of identifying and using genetic diversity in the USDA germplasm collection for the benefit of the consumer. Objective 1, the improvement of yield potential, will employ innovative breeding methods and QTL analysis of breeding populations derived from exotic germplasm, including wild soybean. Objective 2, the improvement of seed composition, will focus on raising oleic acid content of soy oil, reducing phytate in the protein meal, identifying allergenic epitopes in soybean seed storage proteins and determining the impact of altered seed composition on vulnerability to disease. Objective 3, the improvement of stress tolerances will identify QTL in exotic germplasm for tolerance to drought and ozone. All of these objectives focus on increasing the profitability of the U.S. crop. A common factor in the three objectives is the placement of novel alleles and traits in high-yielding publicly-available genetic backgrounds. Because more than 90% of the U.S. soybean acreage is grown in private varieties, industry rather than the public sector will be the most immediate user of this USDA-ARS-developed germplasm as novel breeding stock. However, our products are non-GMO and, thus, are also being used directly in the small- but fast-growing- organic market. To ensure the successful transfer of USDA products to the farm (directly to organic or indirectly as breeding stock for the larger industry) it is essential that our USDA-ARS germplasm releases be ‘user friendly’. Thus, germplasm released in the project must yield within 5% of current commercial types. The highly productive and expansive ARS field program, which is the basis for this project and its objectives, makes this goal achievable.