Combining ability in rice was studied with a set of 5 lines and 10 testers and their 50 hybrids. The magnitudes of sca variances were higher than gca variances for all the characters except days to 50 per cent flowering and plant height, which indicated that non-additive gene action was predominant in the expression of these traits. The estimation of gca effects for parents revealed that female, IR-87707-182-B-B-B and males SPRV -1 and IRRI -AMT -301 were good general combiners for yield and yield contributing characters. The best specific cross combinations obtained through average x poor and good x average combining parents respectively for grain yield per plant.
Combining ability, gene action, line x tester, rice, yield, yield components
