DIALLEL CROSSES FOR ESTIMATION OF COMBINING ABILITY FOR YIELD AND AGRONOMIC ATTRIBUTES IN MAIZE

Abstract

The present study was carried out to estimate combining ability of 36 hybrids generated by crossing 9 new maize inbred lines in a half diallel model in 2013 season at two locations of Sids and Gemmeiza Agric. Res. Stns. The experiment was laid out in a randomized complete block design with four replications. Number of days to 50 % silking, plant height, ear height, ear length, ear diameter and grain yield (Ard / Fed) were determined. The mean squares, due to general combining ability (GCA) and specific combining ability (SCA) were highly significant for all studied traits. There was preponderance of additive gene action for all studied traits. Estimates of GCA and SCA effects showed that parental lines P6 and P8 were generally good combiners for earliness, shortness and lower ear placement, while, P2, P3 and P9 were good combiner for grain yield and can be included in future improvement maize breeding programs. Two crosses exhibited desirable SCA effects for grain yield, four hybrids significantly out yielded the highest yielding check hybrids SC. 162, and twelve hybrids did not differ significantly than the check. These hybrids may be released as commercial hybrids after further testing and evaluation. It could be concluded that P2, P3 and P9 was found to be a good GCA can be used in synthetic variety and hybrids ( P1 x P2 ) and ( P7 x P8 ) was found to be a good combiner and can use as a potential single cross hybrid combination and tester further.