Identification of micro satellite markers on chromosomes of bread wheat showing an association with karnal bunt resistance

A set of 104 wheat recombinant inbred lines developed from a cross between parents resistant (HD 29) and susceptible (WH 542) to karnal bunt (caused by Neovossia indica) were screened and used to identify SSR markers linked with resistance to karnal bunt as these would allow indirect marker assisted selection of karnal bunt resistant genotypes. The two parents were analysed with 46 SSR primer pairs. Of these, 15 (32%) were found polymorphic between the two parental genotypes. Using these primer pairs, we carried out bulked segregate analysis on two bulked DNAs, one obtained by pooling DNA from 10 karnal bunt resistant recombinant inbred lines and the other similarly derived by pooling DNA from 10 karnal bunt susceptible recombinant inbred lines. Two molecular markers, Xgwm 337-1D and Xgwm 637-4A showed apparent linkage with resistance to karnal bunt. This was confirmed following selective genotyping of individual recombinant inbred lines included in the bulks. These markers may be useful in marker assisted selection for karnal bunt resistance in wheat.