Combining ability analysis for yield and its contributing characters in cucumber

Abstract

Combining ability was studied in cucumber in a 10 × 10 diallel cross excluding reciprocals for ten important quantitative characters including total yield per plant, maturity and fruit characters. The mean square due to gca and sca were highly significant for all the characters studied which revealed that both additive and non-additive gene actions were important in the inheritance of these characters. Hence, for the improvement of these traits, both selection and heterosis methods of breeding can be adopted. The estimated components of variance for sca were larger than those of gca. This indicated that the superior performance of F1 hybrids showing high sca was largely due to epistasis interaction. Among 10 parental lines, the parent P1 (DC-1) showed highest gca for fruit weight, fruit length and total yield per plant and parent P3 (DC-2) exhibited maximum favourable gca for node number of first female flower and number of fruits per plant. In order of merit, the hybrid P7 × P8 (PCUC-28 × VRC-11-1), P1 × P7 (DC-1 × PCUC-28) and P4 × P6 (CH-20 × Himangi) were found to be the top performing hybrids over top parent for total yield per plant. These F1 hybrids showed highly significant sca effects for yield and its important contributing characters. The results of this study suggests that for improvement of a desirable character, the selected parental line should be of high gca value and their F1s should express high specific combining ability.