2010 Annual Report
Enhancing Sclerotinia resistance in soybean: Management strategies for Sclerotinia stem rot or white mold of soybean have limitations. Crop culture modifications often compromise high yield, fungicides add to production costs, and resistance found to date is partial, multigenic, and complex. This project brings together expertise and results from identification of genes involved in resistance to Sclerotinia sclerotiorum in soybean and basic research on plant defense mechanisms in response to fungal pathogen infection. The LysM-encoding genes are known to be involved in reaction to fungal infection, and some of these have been mapped to regions in the soybean genome previously identified as quantitative trait loci (QTL) for resistance to sclerotinia stem rot. This project is focused on the LysM domain encoding genes and mapping them in two soybean recombinant inbred line populations that were used previously to identify quantitative trait loci for resistance to sclerotinia stem rot. We are correlating the map locations of the LysM-encoding genes with those of the identified QTL. In addition, we are developing polymorphic SNP markers for the LysM genes that map close to existing QTL. These genes represent promising candidate genes that would explain the resistance to white mold in selected cultivars. Genetic markers developed against these LysM-domain encoding genes should be useful for molecular assisted selection to move the favorable QTL loci into elite lines of soybean.