Estimation of General and Specific Combining Abilities of Morphological Traits and Grain Yield in Bread Wheat

Five wheat varieties were used to estimate gene action for morphological traits and yield and estimate the heritability of traits. The varieties including White Bolani, Brown Bolani, Tajan, Kealk and AS48 mutant have been crossed based on full diallel. The F2 genotypes were planted in a randomized complete block design with three replications in the Nuclear Agricultural Research Institute. Analysis of variance for all the traits revealed that the general combining ability was significant so these traits were controlled by additive genetic effects. The heritability of traits were high and therefore selection based on these will be successful. Additive-dominance model was sufficient for this research and non-allelic effect weren’t observed, therefore Hayman analysis was performed. Hayman’s analysis of variance showed that the additive effects and non-additive effects control the traits. For number of spikelet per spike, second and third internodes diameter, second and third internodes length and leaf area traits, the average degree of dominance indicate that partial dominance controls these traits. Heyman’s graphical analysis showed that partial dominance was involved in controlling these traits.