Development of semi-dwarf bacterial blight disease resistant lines of “Ranbir Basmati”
In the current study, a marker-assisted backcross breeding (MABB) strategy was employed to transfer two bacterial blight (BB) resistance genes (Xa21 and xa13) alongside a dwarfing gene (sd1) into Ranbir Basmati. The molecular markers, specifically pTA 248, xa13prom and h, which are associated with Xa21, xa13 and sd1 respectively, were utilized in the MABB programme. Both foreground and background selection methods were applied to pyramid the genes of interest into the variety. Crosses were conducted to integrate the BB resistance genes and the dwarfing gene from Punjab Basmati 4 (Xa21, xa13 and sd1) into Ranbir Basmati. The MABB programme progressed up to the BC3F6 generations. A total of four semi-dwarf pyramided lines, namely SJBR 145-22, SJBR 145-34, SBJR-129-06 and SBJR-139-14 have been identified for subsequent field screening. These pyramided lines exhibited excellent cooking qualities and a pleasant aroma. Further evaluations of these four lines for morpho-physiological and quality traits indicated the potential donors for various rice pre-breeding programmes.