Combining ability analysis on of quantitative traits in rice bean Vigna umbellata [(Thunb.)Ohwi. & Ohashi] was studied using 6 x 6 parents half diallel cross in the F1 generation. The variancesdue to gca (except for clusters/plant) and sca were highly significant, indicating the prevalence ofadditive and non-additive gene action for all the traits studied. The estimates of gca components werehigher than sca components for all the traits, except clusters/plant indicating the predominance of theadditive gene action for the traits. Parents RBL-50/PRR-2, RBL-6/RBL-1, were good generalcombinations for pods/plant and clusters/plant respectively. RBL-17/KHRP-2, RBL-6/KHRP-2 andRBL-6/PRR-2 were good specific combinations for grain yield.
Key words: Combining ability, quantitative traits and rice bean.