Combining Ability and Heterosis in French Bean

A diallel cross set of 7 × 7 was analysed for combining ability variances and effects for seed yield, 100-seed weight and protein content in French bean. Heterosis was studied in the F_t populations. Both additive and non-additive gene action were predominent for seed yield and protein content, where as additive gene action was predominent for 100-seed weight. In the F_l generations, the mean heterosis was 76.0 per cent for yield, 35.00 per cent for 100-seed weight and 8.90 per cent for protein content. This indicated the importance of non-additive (presumly additive × additive type) gene action for the characters studied.