Assessment of breeding potential of determinate and indeterminate vegetable cowpea genotypes through multivariate analysis for ideotype breeding

The development of a vegetable cowpea variety that is adaptable to diverse agricultural production systems and has a short, non-vining stem, early maturing and constant green pod bearing, medium-long, meaty pods and a high pod protein content is urgently needed. Using both determinate and indeterminate cowpea genotypes, it is necessary to identify genetically diverse parents for the creation of such a cowpea ideotype. Twenty-four vegetable cowpea genotypes involving both determinate and indeterminate types were assessed for 18 quantitative traits. Genetic variability, correlation and genetic divergence through multivariate analysis were estimated as per the standard procedure through software packages. Based on pod yield, Maharani Laffa Barbati, Kashi Nidhi and Lal Laffa were found superior irrespective of genotypes and need to be critically tested before commercialization. Plant height, branch number per plant, total pickings, marketable pod length, number of marketable pods per plant, seeds per pod, marketable pod weight and yield per plant showed high genetic coefficient of variation, heritability and genetic advance and were primarily governed by additive genetic influences. Pod weight and number of marketable pods per plant were identified as important selection indices for improvement of pod yield. Genetic diversity could not be adequately measured by geographic diversity alone. Three principal components, pod length, plant height and pod protein content, accounted for 95.60 % of the variation irrespective of genotypes, with eigenvalues greater than 1. Based on cluster analysis and scatter diagram of principal component analysis, indeterminate genotypes Asutosh, Vayjayanthi, Shweta, Arya Vaibhav Laxmi and determinate genotype Pusa Komal were found most diverse and could be used as potential donors. The future breeding strategies for the development of cowpea ideotype were discussed.