Location: Sunflower and Plant Biology Research
Project Number: 3060-21220-028-26-S
Project Type: Specific Cooperative Agreement
Start Date: Jun 1, 2014
End Date: Sep 30, 2017
The long-term goal of this project is to develop soybean varieties or germplasm that have a high level of resistance to Sclerotinia stem rot (SSR). The short-term supporting objectives are: 1. evaluate advanced breeding lines for resistance to SSR and for agronomic performance, and release the best lines as germplasm or varieties; 2. evaluate a diverse set of 280 soybean plant introductions (PIs) for resistance to SSR; 3. validate SNP markers that were found associated with resistance to SSR in our genome wide association studies.
For objective 1, over 70 advanced breeding lines derived from multiple sources of resistance to Sclerotinia will be evaluated at seven locations in Michigan for yield and agronomic traits. The lines will also be evaluated for resistance to SSR in a Sclerotinia disease nursery and in the greenhouse with the drop-mycelium method developed by us. About 15% of the lines will be selected based on their resistance to SSR, yield, and other agronomic traits. The selected lines will be re-evaluated in our disease nursery for resistance to SSR and yield under disease pressure. Five to 10 lines will be selected and tested in the Uniform Soybean Tests – Northern Region (19 locations in 10 northern US states and 1 Canadian province), for yield and other agronomic traits. The best lines will be released to the public. For objective 2, a diverse set of early maturing (maturity groups I, II and III) 280 soybean plant introductions selected based on 52,041 SNP marker data will be evaluated for resistance to SSR in a naturally infected Sclerotinia disease nursery and in the greenhouse with the drop-mycelium method. For objective 3, over 500 breeding lines developed by crossing SSR resistant parents with SSR susceptible parents will be evaluated for resistance to SSR in the disease nursery and in the greenhouse. These lines will also be genotyped with SNP markers that were found associated with SSR resistance in our genome wide association studies. The SNP marker data and the disease resistance data will be analyzed together to validate the association of the SNP markers with resistance to SSR.