Introgression of Blast Resistance Gene Pi-kh into Elite indica Rice Variety Improved Samba Mahsuri

Improved Samba Mahsuri, a bacterial blight resistant variety, developed through marker assisted selection is identical to Samba Mahsuri except for three bacterial blight resistant genes, but is susceptible to blast disease. Hence, an attempt was made to introgress the blast resistance gene Pi-kh from donor Tetep which is highly resistant to the rice blast fungus Magnaporthe grisea. The molecular markers used were PTA 248 for bacterial blight resistance gene Xa21 and RM 206 for blast resistance gene Pi-kh in the segregating population and the resultant resistant progenies were analyzed through phenotypic assays with bacterial blight and blast pathogens. This work demonstrates the successful application of molecular markers for targeted introgression of a dominant blast gene (Pi-kh) into a rice cultivar Improved Samba Mahsuri with existing bacterial blight resistance genes.