Soybean cyst nematode (SCN) causes by far the most yield loss of any pathogen of soybean in the U.S. This project is developing new tools for SCN control. Three different genetic resistance strategies are being developed. a) Identify the causal gene and mechanism for SCN resistance locus cqSCN-007. b) Create and test soybean lines that express more, or new combinations of, Rhg1 proteins (Rhg1 contributes the best SCN resistance known at present). c) Breed soybean lines with new combinations of multiple quantitative SCN resistance loci, and develop/publicize more efficient breeding methods to do the same. The project is also investigating: d) Chemical treatments that alter the soybean plant’s SCN resistance. These findings will help the industry to develop new approaches to stay ahead of the ongoing evolution of SCN toward higher virulence on presently available soybean varieties. In FY2024, strong progress continued on all four of the present project aims as significant research advances were obtained, new soybean germplasm was developed and planted, and multiple peer-reviewed scientific manuscripts were submitted or published.

These findings will help the industry to develop new approaches to stay ahead of the ongoing evolution of SCN toward higher virulence on presently available soybean varieties. Farmers who use better SCN control methods will realize significant soybean yield increases.