Inheritance of Resistance to SMV3 and Identification of RAPD Marker Linked to the Resistant Gene in Soybean

One SMV resistant soybean line (95-5383) was crossed with four susceptible soybean varieties/line ( HB1, Tiefeng21, Amsoy, Williams) and one resistant introduced line PI486355. Their F1 and F2individuals were identified for SMV resistance by inoculation with SMV3. The results showed that in the four crosses of resistant × susceptible, F1 were susceptible and the ratio of F2 populations was 1 resistant : 3susceptible (mosaic and necrosis), indicating that 95-5383 carries one recessive gene that confer resistance to SMV3. There is segregation of susceptibility in F2 progenies from the cross of 95-5383 × PI486355, indicating that the SMV3 resistant gene in 95-5383 is located at different locus from PI486355. By bulked segregating analysis (BSA) in F2 populations of 95-5383 × HB1, one codominant RAPD marker OPN11980/1070 closely linked to SMV3 resistance gene amplified with RAPD primer OPN11 was identified. The DNA fragment OPN11980 was amplified in resistant parent 95-5383 and resistant bulk, and OPN111070 was amplified in susceptible parent HB1 and susceptible bulk. OPN11980/1070 was amplified in F1. Identification of the markers in F2 plants showed that the codominant marker OPN11980/1070 is closely linked to the SMV resistance locus in95-5383, with genetic distance of 2.1cM.