Estimation of Genetic Parameters in Bread Wheat (Triticum aestivum L.) Genotypes Evaluated Under High Temperature Yield Trial in Ethiopia

The study was carried out to estimate genetic parameters of 49 bread wheat genotypes and standard check evaluated at Kulumsa and Melkasa using alpha lattice design with two replications. The analysis of variance result showed highly significant differences among the genotypes for all traits (P< 0.001), implying the presence of considerable genetic variability for these traits. Out of 50 genotypes, four genotypes such as EBW2113062, EBW2113039, EBW2113037 and EBW2113056 were the top yielding genotypes across the locations. Furthermore, 30 of the 50 genotypes gave grain yield above grand mean whereas 14 genotypes had grain yield above the check, Dursa(1295.05kg/ha). In the other word, about 60% of genotypes were with mean grain yield above the overall mean and 30% of them provided mean grain yield above the check, Dursa, variety. High and moderate heritability estimates were found for most of traits showing that the variation observed was mainly under genetic control. The highest PCV and GCV values were observed for grain yield at both locations indicating better opportunity for improvement in this trait via selection. The phenotypic coefficient of variation (PCV) was generally higher than the genotypic coefficient of variation (GCV) for all characters at both locations. The difference between PCV and GCV was large in TKW followed by PHT and Grain yield indicating that these traits are influenced by the environment. However, differences between them were small for most of the traits indicating low effect of environment on the expression of characters at both locations. The genotypic correlations between grain yield with thousand kernel weights and hectoliter weight were highly significant showing their important contribution to grain yield. Therefore, the identified genotypes with better performance could be utilized in advanced bread wheat yield trial targeted for high temperature condition in the country.