Identification of coupling- and repulsion-phase markers in rice for brown planthopper resistance genes using F 2 S of IR 50 X CO 46

Brown planthopper, Nilaparvata lugens Stal (Homoptera: Delphacidae) is one of the most threatening pests, often significantly reducing the rice yield. The breeding of resistant cultivar has been the most effective way of controlling this pest. Recent advancements in DNA marker technology together with the concept of marker-assisted selection (MAS) provide new solutions for selection of more durable brown planthopper (BPH) resistant genotypes in rice. F2s of a cross between IR 50 and CO 46 and their susceptible and resistant parents were used for the present study. In bulk segregant analysis, random amplification of polymorphic DNA (RAPD) primer, OPC 11 (5’AAAGCTGCGG 3’) showed co-dominant banding pattern, which amplified a susceptible phenotype specific marker OPC11856 associated with repulsion phase. It also amplified resistant phenotype specific markers, OPC 11817 which are associated in coupling phase to the resistant allele. The OPA11817 RAPD marker could be used in a cost effective way for marker assisted selection of BPH resistant rice genotypes.