Title: Combining Ability Estimate And Gene Action In Maize Under Water Stress And Non Stress Conditions
Authors: Solomon Z. S., Jonathan J. S., Samuel A.
Volume: 9
Issue: 10
Pages: 239-248
Publication Date: 2025/10/28
Abstract:
This study analyzed the combining abilities of 6 parents and F1 hybrids developed from 6 x 6 diallel combination evaluated under water stress and non stress conditions for drought tolerance and yield and yield components at Minna and Jebba locations during the 2022 cropping season. The experiment was laid out in a randomized complete block design with three replications. Traits studied include, plant height, ear height, number of grains per cob, number of grain row per cob, number of grains per row, total grain per cob. The results of the general combining ability (GCA) indicated significant differences among the parents and specific combining ability (SCA) for crosses for all the traits studied. Estimate of GCA effect for grain yield per plant showed that the genotype (W.DT STR Syn/TZL COMP1-W) F2 and TZL COMP1-W C6/DT-SYN-1-W were positively significant under stress condition and were identified as the best general combiner for the trait. The poorest general combiners were genotypes DT Syn-1 F2 and DT SYN 13-W F1 under stress condition. The best specific combination was (W.DT STR Syn/TZL COMP1-W) F2 X DT SYN2-W F1 for grain yield per plant under stress condition. Components of variance relative to GCA and SCA effects revealed that only cob length under non stress condition was controlled by additive gene action among the traits measured under both conditions. The importance of both additive and non-additive genetic variability was identified as the overall result of this study; therefore the use of integrated breeding strategies which can efficiently utilize the additive and non-additive genetic variability can be employed in breeding programs.