Estimation of Inheritance Leaf Rust, Powdery Mildew, Yield and Yield Components in Barley through Generation Means Analysis

The success of breeding program for improvement any crop depends mainly on the available background of the inheritance of the studied traits to be selected. This study was carried out during 2018/2019, 2019/2020 and 2020/2021 grown seasons at the experimental farm of Sakha Agricultural Research Station, Agricultural Research Center, Egypt to estimate the effect of genetic parameters controlling yield and yield component traits in addition severity of leaf rust and powdery mildew disease infection. Six generations (P1, P2, F1, F2, BC1 and BC2) model was used. Results indicated that, mean effect (m) was highly significant in all evaluated crosses for all studied traits. The relative importance of additive and dominance effects differed from trait to another in each cross. For epistatic components, dominance × dominance interaction effects were more effective than other components in most studied traits. Significant or/and highly significant values in desirable direction of heterosis compared to mid and better parent were obtained from most studied crosses in yield and its attribute traits, but it found over mid parents only for cross no.1 in leaf rust and crosses no. 1 and 2 in powdery mildew infection. The estimation of broad-sense heritability showed high values for studied traits and crosses, while narrow-sense heritability and genetic advance from selection ranged from low to medium in most crosses for the agronomic traits, while it ranged from low to high for leaf rust and powdery mildew infection. Finally, the results of this study recommended the barley crosses no. 4 for improve yield potential and resistant to leaf rust and cross no. 5 to improve resistance to powdery mildew, where it had high genetic advance associated with high heritability.