Genetic analysis and identification of two soybean mosaic virus resistance genes in soybean [Glycine max (L.) Merr]

Abstract Soybean mosaic virus ( SMV ) commonly affects soybean production worldwide, and the SC 18 strain has been widespread in C hina. This study aimed to characterize and map the SC 18 resistance genes present in soybean cultivars ‘ K efeng N o. 1’ and ‘ Q ihuang 22’. Inheritance analysis revealed that two independent single dominant genes in K efeng No. 1 and Q ihuang 22 confer resistance to SC 18. Using simple sequence repeat ( SSR ) markers and bulked segregant analysis, the K efeng No. 1 and Q ihuang 22 resistance genes were located on soybean chromosomes 2 and 13, respectively. We further screened two populations of recombinant inbred lines with 32 SSR markers in the target region, where the resistance gene in K efeng No. 1 was fine mapped to an 80‐kb region containing six putative genes. Sequence and expression analyses of these genes revealed that SMV resistance in K efeng No. 1 was probably attributable to three of the candidate genes (i.e. Glyma.02G127800 , Glyma.02G128200 and Glyma.02G128300 ). Collectively, the results of this study will greatly facilitate the cloning of SC 18 resistance genes and marker‐assisted breeding of SMV ‐resistant soybean cultivars.