Mapping powdery mildew resistance gene in V97‐3000 soybean

V97-3000 is a maturity group (MG) V soybean breeding line derived from SS 516xV90-2592 (VancexV81-1325) with high stachyose, small seed and powdery mildew resistance. A total of 53 F-2:3 families were derived from a cross between V97-3000 and a powdery mildew susceptible line V99-5089. The 53 F-2:3 families, each with 30 plants, were grown in the greenhouse for powdery mildew evaluation, and the corresponding 53 F-2 plants were genotyped using simple sequence repeat (SSR) markers. Results showed that the 53 F-2:3 families segregated in ratio of one resistant : two segregating : one susceptible (13:26:14) and the 26 segregating F-2:3 families each exhibited a good fit to three resistant : one susceptible, indicating that resistance to powdery mildew is conditioned by a single dominant gene. The gene for powdery mildew resistance in V97-3000 was mapped on chromosome 16 [linkage group (LG) J] flanked by Satt547 and Sat_396 on one side and Sat_393 on the other side with 3.8 cM and 3.9 cM distance, respectively. This study provides a new source of powdery mildew resistance and information of genetic location of the resistance gene and linked markers, which is useful for breeders selecting powdery mildew resistance through marker-assisted selection (MAS) in soybean breeding programmes.