Genetic Analysis and Mapping of Resistance Gene to Seed Coat Mottle in Soybean

Abstract

Soybean mosaic virus(SMV) causes a worldwide disease in soybean,reducing yield and making mottling of soybean seeds,and so largely losing soybean economy value. Resistant variety breeding is the most effective way to protect against the seed coat mottle. In this study,an F2:3 population,derived from Dongnong 3C624(susceptible) × Dongnong 8143(resistant) ,was used to study the genetic mechanism of the resistance,and map the resistant gene of seed coat mottle by simple sequence repeat(SSR) markers with bulked segregation analysis(BSA) method. Two parents and their F2,F3 population were inoculated with SMV strain No.1 in 2006 and 2007. Identification results in two years showed that resistance to SMV strain No.1 of Dongnong 8143 was controlled by one pair of dominant genes. Six hundred pairs of SSR primers were screened,and five SSR markers,Sat_297,Sat_229,Sat_317,Satt335,and Sct_188,were mapped near the resistance gene. Linkage analysis indicated that the re-sistance gene locus was located on the linkage group F. The order and genetic distance among the resistance gene and markers were Sat_297–12.4 cM–Sat_229–3.6 cM–SRSMV1–1.7 cM–Sat_317–2.4 cM–Satt335–13.8 cM–Sct_188. Sat_229,Sat_317,and Satt335 can be used for molecular assisted breeding.