Marker assisted introgression of semi-dwarfing (sd1) gene in Katarni rice (Oryza sativa L.) landrace

‘Katarni Rice’ is a fine quality scented rice landrace of Bihar, India and has tremendous export potential and commercial value. This is a preferred rice in the state due to its flavour, palatability and popcorn like essence before and after cooking. But its area has been shrunken drastically in recent years due to its low yielding (25–30 Q/ha) ability caused due tall and week stature and lodging tendency at maturity. To overcome this problem, marker assisted introgression of semi-dwarfing (sd1) gene from semi-dwarf and high yielding rice varieties Rajendra Sweta and BPT5204 was attempted. Parental polymorphism was obtained through 109 SSR markers. The gene specific markers for fragrance and semi-dwarfing genes were used in the segregants to track their transfer. Recombinant selection was done for the donor genome segments flanking to the target gene i.e., sd1 followed by background selection through genome wide polymorphic SSR markers. More than 90% recurrent parent genome recovery was observed and the selected plants showed a reduction of plant height and flowering time in comparison to Katarni in the successive backcross generation along with the retention of aroma. The identified lines can be evaluated further in multilocation trials to release it as a sustainable high yielding aromatic genotype.