Identification of Genes for Resistance to Blast (Magnaporthe oryzae): Molecular Breeding Strategies for Improvement of Rice (Oryza sativa L.)

Twenty two elite Indica rice genotypes were evaluated for resistance against blast disease under induced artificial epiphytotic conditions. Screening of rice genotypes for blast resistance was based on disease severity (%) and AUDPC on different growth stages. Only thirteen rice genotypes expressed resistance against the blast disease. The rest nine rice genotypes, which were susceptible under artificial epiphytotic conditions, also carried blast resistance genes as indicated by gene linked markers. The two rice genotypes VLD-61 and Vallabh basmati-22 had no resistance genes, however, expressed strong resistance against blast. The genes responsible for blast resistance were identified with the help of ten gene specific primers. Breeding strategies for development of blast resistant improved varieties of rice involving the varieties identified herein as donors for the genes for blast resistance were also discussed.