MARKERASSISTED BREEDING FOR RESISTANCE TO BACTERIAL LEAF BLIGHT IN POPULAR CULTIVAR AND PARENTAL LINES OF HYBRID RICE
M.L. Shanti, V.V. Shenoy, G. Lalitha Devi, V. Mohan Kumar, P. Premalatha, G. Naveen Kumar, H.E. Shashidhar, U.B. Zehr, W.H. Freeman
Molecular markers are becoming essential components in breeding programs involving gene pyramiding. Using marker-assisted selection in a backcross-breeding program, four bacterial blight resistant genes namely Xa4, xa5, xa13 and Xa21 have been introgressed into the hybrid rice parental lines KMR3, PRR78, IR58025B, Pusa 6B and the popular cv. Mahsuri. Only foreground selection was done using markers. Conventional breeding strategy was adopted for background selection. The pyramids showed very high level of disease resistance to 10 highly virulent isolates of Xanthomonas oryzae pv. oryzae. Grain quality parameters of the pyramids were on par with that of the original genotype. This work reports the successful application of marker-assisted breeding for pyramiding simultaneously four bacterial blight resistant genes into multiple backgrounds. These lines can be used directly or can be used as donors of bacterial blight (BB) resistance breeding.