DETECTION OF EPISTASIS COMPONENT OF VARIATION FOR YIELD CONTRIBUTING TRAITS OVER TWO ENVIRONMENTS IN BREADWHEAT

Abstract

The component of genetic variation were studied in 54 TIC progenies over two environments for grain yield and its component traits. The overall epistasis (i Type) was present for all the characters except number of ear bearing tillers and spike length under late sown conditions and weight of grains per spike under timely sown conditions. However, j and I type of epistasis was more pronounced than i type in both environments for all the characters. Both the additive and dominance components of genetic variation were highly significant for all the traits. All the attributes exhibited high heritability estimates under both the environmental conditions except ear bearing tillers under late sown conditions. The additive and dominance gene effects were equally sensitive to the change in environment. The j and I components of epistasis were more sensitive to environment than i component. The possible application of genetic variances prediction in wheat improvement programme has been discussed.