Combining Ability in Okra

The present investigation was undertaken on combining ability in okra in a 10 × 10 diallel set excluding reciprocals. The variance due to gca and sea was highly significant. The mean squares for gca were larger than sea for all the characters. The ratio of S²A/S²D indicated high values of S²D for most characters except pod weight, pod thickness and height at first fruiting node. None of the parent was good in respect of all the characters. However, the parents P-6, P-l and P-7 for days to 50 per cent flowering and pod number; P-9 and P-4 for pod weight; P-4, P-6 and P-7 for pod length; P-9 and P-10 for pod thickness; P-6 and P-l for pod yield; P-6, P-7 and P-4 for height at first fruiting node, P-l, P-8 and P-10 for plant height; P-7, P-l and P-6 for branches number; P-7, P-4 and P-l for internodal distance and P-9, P-4 and P-10 for seed number showed high gca effects. The specific cross combinations, P-l × P-2 and P-l × P-3 topped for pod yield, pod number, pod weight, plant height and branches number.

The characters like pod number, pod length, pod yield, plant height, branches number, internodal distance and seed number were under the major influence of non-additive gene action, where the heterosis breeding may be followod. Days to 50 per cent flowering where both additive and non-additive gene action centres, the reciprocal recurrent selection or reciprocal fullsib may be effective. Pod weight, pod thickness and height at first fruiting node where gene action is mainly additive, it is suggested to adopt simple selection procedures for fixing and improving these characers.