Project Number: 8042-21000-289-49-R
Project Type: Reimbursable Cooperative Agreement
Start Date: Oct 1, 2020
End Date: Sep 30, 2021
The purpose of the project is to discover genetic sources from wild soybean for the development of new soybean varieties with improved meal protein. The protein content of U.S. commercial soybean seed has been declining for decades. Decades of breeding focused on increased yield with little attention to protein has resulted in decreased protein in U.S. soybean. The lower protein of soybean puts U.S. growers at a disadvantage in the global marketplace. In the past 70 years, intensive breeding and selection has resulted in dramatically reduced genetic variability of modern U.S. soybean cultivars. Wild soybean has higher protein level compared to commercial cultivars, however, genetic variability of protein from wild soybean has rarely been exploited for the genetic improvement of cultivated soybean. Although many QTL controlling soybean seed protein and other traits have been mapped, most QTL have been identified in U.S. elite germplasm, omitting a vast pool of potentially favorable alleles for these traits from wild soybean. It is important to mine this gene pool. In addition, fine mapping high seed protein and oil QTL from wild soybean will help geneticists and breeders to identify these genes and to introgression desired genes using tightly linked markers. Thus, our objectives are to identify and fine map new major QTL controlling protein concentration in wild that have not been discovered and can be used to improve the cultivated soybean, and to develop breeder-friendly genetic markers for targeted protein genes to assist development of high quality germplasm with high protein levels.
Based upon the analysis of the nearly 1,200 wild soybean accessions in the USDA Soybean Germplasm Collection that have been analyzed with more than 50,000 SNP DNA markers a core collection of 81 wild soybeans were identified. F6 seeds were obtained by crossing the wild soybean accessions of the core subset with elite soybean cultivars by collaborators. The F6-derived recombinant inbred lines (RILs) from 10 cultivated x wild crosses will be genotyped with BARCSoySNP5K/Soysnp50k BeadChips or sequencing. The RILs will be evaluated for protein content and other seed compositions in two years. The genotypic and phenotypic data will be used to identify loci and haplotypes that are associated with high protein content and are specific in wild accessions. The identified genes will be introduced to elite cultivated soybean by collaborators.