Heterosis and combining ability studies in single cross hybrids synthesized with diverse inbred lines of maize (Zea mays L.)

Combining ability and heterosis analysis were performed in ten lines, five testers and their fifty hybrid combinations of maize using line x tester analysis. Combining ability analysis among the sixteen traits revealed significant line x tester interaction for most of the traits studied. Variance due to sca was found to be more than gca for all the traits studied which indicated the preponderance of non-additive gene action. Among the parents, the lines viz., N67, N10-65-3, N10-153-1-2 and the tester UMI 1210 exhibited higher per se along with positive gca effects and found to be good general combiners among the parents. Standard heterosis was calculated by comparing TNAU maize hybrid CO 6 as the standard check. Considering the per se, sca and standard heterosis, single cross hybrid N10-65-3 x E.No.8 was identified as the best hybrid for grain yield and other major yield contributing traits followed by the hybrid N44 x UMI 1221.