Development of biotic stress resistant version of CO 51 Rice cultivar through Marker Assisted Introgression of major genes, Pi9 and Xa21

 Rice, is a staple crop for the global population and faces significant challenges from diseases viz., blast and bacterial blight. To combat these biotic stresses, Marker-assisted selection is employed for the development of resistant breeding lines against the concerned stresses. This study successfully demonstrated the stacking/pyramiding of Pi9 and Pi54 genes for blast resistance (Magnaporthe oryzae) and Xa21 gene for bacterial blight resistance (Xanthomonas oryzae p.v oryzae) and stringent phenotypic screening in the early generation of CO 51 X 562-4. Recurrent parent, CO 51 scored 5.0 for blast as a moderately resistant and susceptible reaction to blight screening. Among the five breeding lines of F4, blast resistance ranged from 1.5 to 3.8, while blight disease ranged from 0.6 to 0.7 cm as a resistant reaction. Progeny #6-28-3 recorded resistant reactions to blast and blight disease followed by Progeny #6-28-4.