Progressive Agriculture

Heterotic expression and combining ability was studied for fifteen yield and related traits in maize involving 66 F₁ crosses produced in line x tester design. Pooled analysis of variance revealed significant differences among lines, testers and line x tester crosses except for leaves per plant and ear girth due to testers. Inbred lines L9. L13, L14, L15 and L18 were good general combiners for earliness; L2, L3 and L5 for higher plant height, ear height and number of leaves per plant, L2 and L3 for ear length, ear girth, kernel rows ear, kernels per row, 100 kernels weight, grain yield per plant, dry stover yield per plant and biological yield per plant. On the basis of SCA and per se performance, hybrid L15 x T3 idetified as early in flowering traits. Crosses L19 x T3, L7 x T3 and L11 x T3 revealed high SCA effects for grain yield per plant. When one or both the parents were poor general combiners, they resulted into a hybird having highly significant SCA effects upon crossing. This is exemplified by hybird L19 x T3 for ear length, kernel rows, kernels per row, 100 kernel weight, grain yield, dry stover yield and biological yield. High percentage of better parent heterosis and standard heterosis for grain yield per plant was recorded by hybird L3 x T1 and L3 x T3, respectively. Hybrid L3 x T1 had considerable higher desirable heterosis over better parent for days to 50 per cent silking, days to maturity, leaves per plant and ear girth and standard heterosis for plant height, ear girth and kernel row per ear.