Mapping of Powdery Mildew Resistance Gene in Melon PMR5

Taking the powdery mildew resistance variety PMR5,susceptible variety Jiashi,F1,BC1 and BC2as materials,and the powdery mildewPodosphaera xanthii race 1was inoculated.The method of resistance genetic analysis,Bulked Segregation Analysis(BSA)and Simple Sequence Repeat(SSR)markers were adopted to find the inheritance law of powdery mildew resistance,the markers linked to resistance gene,and then construct the genetic map the gene.The results showed that the resistant and susceptible separation ratio was 64∶27in BC1,and 37∶27in BC2,suggesting that PMR5 provided two dominant genes in BC1,and single dominant gene in BC2.A total of 11 SSR markers in LGII were found to linked powdery mildew resistance gene,and the gene was located in 104 113 bp between markers CMGA36 and SSR25208.