Desai, R. TPatel, S. J2018-06-162018-06-162007-05PATEL SHAILESH JAGANNATHBHAI_37284http://krishikosh.egranth.ac.in/handle/1/5810053553Diallel analysis using eight parents was carried out with a view to estimate heterosis, combining. ability and gene effects in Cowpea (Vigna unguiculata (L.) Walp).The experimental material comprising of eight parents and twenty eight hybrids were planted in a randomized block design with three replications at college farm, N.M.College of Agriculture, Navsari during kharif2005. The analysis. of variance revealed highly significant differences among parents and hybrids for most of the characters studied indicating presence of considerable amount of genetic variability in the material tested. In the present study, high heterotic effects were observed for branches per plant, seeds per pod, seed yield per plant, 100 seed weight. and protein content. Remaining characters which recorded low heterotic effects were 50 per cent flowering, plant height. days to maturity. and pod length. The most heterotic cross for the seed yield was GC-OOll X GC-9710 •followed by CAZC-21 X DCP-2.The high heterotic response for seed yield per plant was mainly due to seeds per pod and 100 seed weight. Combining ability analysis revealed that mean squares due to both general and specific combining ability were significant for all the characters. Specific combining ability variance was predominant for most of the traits. Higher sca variances indicated the importance of non-additive gene effects. As regards to gca effects DCP-2·showed positive gca effects for branches per plant, pod length, pods per plant, seeds per pod, seed yield per plant, I 00 seed weight and GC-OO 12 was good general combiner for plant height, branches per plant, pod length, pods per plant, seeds per pod, seed yield per plant and protein content. The per se performance of parents was more or less related to their gca effects. Crosses showing high sca effects for seed yield per plant also indicated high sea for some of the yield components. The hybrid showing high sea effects for seed yield were resulted from crosses between good x good, poor x good and good x poor combiners. In general , biparental mating and diallel selective mating system could be advocated for accumulation of additive gene effects and breaking up undesirable linkage in order to exploit both additive and non additive genetic components. There is a need to replicate the promising parents and hybrids to different environment and / or locations to collect the information regarding the stability of performance.ennullThesis