Recombinants Screening and High Resolution Genetic Mapping of the rhg1 Locus, and the Identification of Candidate Genes for Resistance to Soybean Cyst Nematode

Soybean cyst nematode (SCN) causes an annual loss of about 1.5 billion to the US soybean industry. Host resistance is an effective management system to control SCN. Two major QTL (The Rhg4 and Rhg1) associated with SCN resistance were identified and mapped in soybean. This work focuses on the rhg1 locus isolation. The recombinants at the rhg1 locus were identified using large F2 derived RILs populations, and the fine genetic mapping of the rhg1 locus using molecular makers developed by Eco-TILLING (Targeting Induced Local lesions IN Genomes) allowed the construction of a high resolution genetic map of this locus. Finally, candidate genes for resistance were identified at the rhg1 locus. Mutation screening of candidate genes at this identified resistant region is underway using TILLING.