Genetic analysis of yield and its components in some bread wheat crosses (Triticum aestivum L.)

To identify epistasis and evaluate genetic variance components in two bread wheat varieties namely (Misr 4 and Giza 171 (and their F1 progeny (Male tester: L1, and L2, plus L3), had crossed with fifteen different bread wheat genotypes using the triple test cross procedure This study was carried out over three growth seasons (2020/2021 through 2022/2023. Exceptions of days to heading, 1000 kernel weight, grain filling duration, and all attributes examined showed considerable epistasis. Additive × additive interaction was significantly greater than the additive × dominance and dominance × dominance interactions. The tow genetic components (dominant and additive) had a significant impact on the inheritance of all traits. For all characteristics except plant height and spike length, the D component was significantly greater than the H one, resulting in (H/D)0.5 being less, suggesting partial dominance. Meanwhile, (H/D)0.5 were more than unity for plant height and spike length, exhibiting the importance effects of dominant gene of genetic control to such traits.