Line × tester analysis for yield and its components of some domestic okra (Abelmoschus esculentus L. Moench) lines

The production of high-yielding and enhanced-quality cultivars of okra has attracted interest from the industry of vegetable seeds production. Thus, field experiments were conducted at El-Baramon Research Station, Horticulture Research Institute. Twenty F₁ hybrids were generated by crossing ten female lines and two male testers using a line × tester mating design. Five hybrids, (L8×T2, L4×T2, L8×T1, L4×T1 and L5×T1), showed higher pod yield compared to the other hybrids. Most of the F₁ hybrids revealed significant heterosis over mid or better parent for yield traits. The best positive heterotic cross was L8×T2 (24.27%) and (17.28%) over mid and better parent, respectively, for pod yield per plant in a desirable direction. Furthermore, the assessments of combining ability variances revealed the predominance of non-additive genetic variance over additive variance in the inheritance of these traits. Specific lines, e.g., L4, L5, L8 and L10 showed favorable gca effects and superior individual performances for pod yield per plant. Cross combinations such as L9×T1, L3×T2, L4×T2, L2×T2 and L5×T1 exhibited desirable sca effects for pod yield per plant along with superior individual performances. The results exhibited that the values of the non-additive genetic variance (σ²D) were greater than those of additive genetic variance (σ²A) for all the traits indicating the major role of non-additive gene effect in the inheritance of the studied traits. Furthermore, the narrow sense heritability varied from 0.49 to 47.37% for pod length and total yield, respectively. To sum up, this study identified superior inbreds, produced promising hybrids, showed desirable specific combining ability action and provided high estimates of useful heterosis, which could be utilized for okra hybrid production.