Genetic analysis of wide-compatibility trait in elite cultivars of indica rice, Oryza sativa L.

Genetic enhancement for higher yield potential through the exploitation of diverse gene pool from the groups of cultivated rice, indica and japonica can be achieved through utilization of wide-compatible varieties which possess neutral allele S5 n for normal spikelet fertility from intersubspecific hybrids. Inheritance and relationship with the marker gene in eight elite indica wide-compatible varieties viz., RP 1579-1701-1318, RP 1967-20503-1241, UPR 1279-1-4-1, Pusa 560-2-20-3-338, Narendra 118, UPRI 95-169, UPRI 95-170 and UPRI 95-174 were studied in 24 three-variety paired test crosses involving wide compatable variety WCV, indica and japonica testers. Inheritance of WC trait in ail the WCY’s was controlled by a single gene with dominance of, wide-compatible over narrow-compatibility. The WC gene in seven of the WCV’s revealed loose linkage with chromogen gene (C+) for anthocyanin pigmentation in apiculus colour on chromosome 6, with mean recombination value of 33.72 %. In the variety Narendra 118, no such linkage was observed as the gene was independent of chromogen gene. The implications of these findings in hybrid and recombination breeding for rice improvement are discussed.

Author : Shalani Gupta and M.P. Pandey