Molecular Mapping of Qtls for Resistance to Brown Spot Disease in Rice

A double haploid mapping population (DH) consisting of 126 lines produced from a cross between IR64 and Azucena was used to detect the quantitative trait loci associated with resistance to brown spot (Cochliobolus miyabeanus) of rice. The whole set of DH population along with parents were evaluated under irrigated and terminal drought conditions. A total of 3 QTLs with LOD score of >3.3 were found to be associated with reaction to brown spot. These QTLs present on Chromosome # 4, 6 & 8 were stable across environment and explained between 9.5 and 18.4% of phenotypic variation.