Genetical Contributions and Combining Ability Analysis in Bitter gourd (Momordica charantia L.)

Abstract

The present study was undertaken to estimate the general and specific combining ability in 10 x 10 diallel set of crosses (excluding reciprocals) in bitter gourd to get 45 hybrids using 10 parents (DVBTG-1, VRBT-94, VRBT-39, VRBT-41, VRBT-49, VRBT-50, VRBT-103, VRBT-63, VRBT-32 and VRBT-6). These 45 F1 along with 10 parents were evaluated in Randomized Block Design with three replications considering 10 characters (days to first male flower anthesis, days to first female flower anthesis, days to first harvest, number of branches/plant, plant height, fruit length, fruit diameter, number of fruits/plant, fruit weight and fruit yield/plant) in bitter gourd. Analysis of variance due to treatment was highly significant for all the traits. The combining ability analysis revealed highly significant differences among the treatments for all the parameters studied. The variances due to sca were higher than the gca for all the characters indicating the predominance of non-additive gene effects. Out of 10 parents’ four parents DVBTG-1, VRBT-49, VRBT-103 and VRBT-32 exhibited significant and   negative g.c.a effects for early female flowering and days to first harvest. Similarly, positive and significant g.c.a effects were shown by DVBTG-1, VRBT-50, VRBT-49, VRBT-103 and VRBT-6 for number of fruits/plant. DVBTG-1 and VRBT-49 showed negative gca effects for the characters except days to 1st harvesting. How VRBT-49 was identified as one of the best general combiners. The cross combinations VRBT-94 x VRBT-32, DVBTG-1 x VRBT-50, VRBT-49 x VRBT-103, VRBT-49 x VRBT-32, VRBT-94 x VRBT-32 and VRBT-41 x VRBT-103 exhibited positive and significant s.c.a effects for first female flower anthesis and days to first harvest. The finding of experiments confirmed the potentiality of DVBTG-1 x VRBT-6, VRBT-94 x VRBT-103, VRBT-41 x VRBT-6, VRBT-94 x VRBT-49, VRBT-39 x VRBT-49 and VRBT-94 x VRBT-39 combination based hybrids for yield/plant. The results of this study also suggest 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. Significant estimates of additive component (d) along with significance of additive x additive (i) gene interaction-with positive sign pod yield per plant which indicated the presence of increase alleles and associated pair of genes.