Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: February 10, 2007
Publication Date: N/A
Technical Abstract: Frogeye leaf spot (FLS) caused by Cercospora sojina K. Hara is a common disease of soybean. Significant yield losses of soybean occur due to FLS under hot and humid growing conditions of the southern USA. Recently, FLS has moved further north into the northern soybean growing states. C. sojina is a dynamic pathogen and its isolates show physiologic specialization for soybean genotypes. Current number of C. sojina isolates at the University of Georgia collection is 93. To facilitate future studies of the genetics of soybean resistance to FLS and the identification of existing and future races of C. sojina, reliable soybean differentials and C. sojina races needs to be defined. Based on the reactions of 93 isolates of C. sojina on 38 putative soybean differentials, a core set of 10 differentials and 13 races are proposed. The definition of these 10 differentials and 13 races should provide the foundation for the identification of additional soybean resistance genes and new races of C. sojina. Rcs3 is the only gene known to provide resistance to all races of FLS in the USA. Rcs3 was mapped on soybean LG J within 1 cM of an SSR marker, Satt244. Recently, five SNP markers within a 2 cM-interval containing Rcs3 have been developed, confirmed, and applied for MAS for Rcs3. The future direction marker assisted breeding for FLS will be presented.