Research Projects

Rice blast caused by Magnaporthe oryzae is a major threat to global rice production, causing 20-30% losses annually. In India, seven blast epidemics have been reported in a span of seven years from 1980 to 1987. Deploying blast resistance genes is considered an economic and environmental friendly approach, but frequent mutations, largely attributed to transposons, allow M. oryzae to evolve and evade the rice defense system, leading to frequent breakdowns in rice's resistance to blast disease. This arms race between rice and M. oryzae emphasizes the importance of isolation and cloning of novel rice blast resistance genes. A broad spectrum, durable rice blast resistance gene, Pi42, was identified from a doubled haploid line DHR9, derived from japonica rice line Fukunishiki. The gene is mapped to chromosome 12 of rice and has been tested for its reaction to blast isolate 'DSN37-1'. Further analysis of nucleotide sequence corresponding to the mapped genomic region in japonica rice cv. Nipponbare has identified a candidate NBS-LRR resistance gene. The proposed project proposes identifying and cloning the candidate blast Pi-42 gene using available genomic resources, and performing functional analysis against blast pathogen through genetic complementation and CRIPSR/Cas mediated editing. The expected results will provide a novel blast R gene Pi42, which will facilitate newer strategies for engineering rice for blast resistance. Deployment of resistance genes is one of the best approaches for rice blast management, but M. oryzae rapidly evolves and overcomes existing rice immunity. Therefore, there is a need for the identification, cloning, characterization, and deployment of novel blast resistance genes, including Pi-42, for effective management of present and future threats posed by blast pathogens.