​Investigations on Per se Performance, Genetic Variability and Correlations in Vegetable Cowpea [Vigna unguiculata (L.) Walp.] Germplasm for Yield and Its Attributing Traits

Background: Cowpea is a multiple-purpose, drought-tolerant, climate-smart and leguminous pulse crop. Recent studies established this crop as a potential vegetable crop with nitrogen fixation ability and round the year cultivation unlike French bean. In several crops, exotic collections imported into India have positive impact in release of new varieties. Per se performance evaluation is the best option for identification of high yielding varieties. Genetic parameters controlling the expression of yield and its components are essential in determining the effect of such genetic parameters and association among the characters enhancing the green pod yield of vegetable cowpea. Methods: A set of eighty seven genotypes of vegetable cowpea including 59 exotic collections imported from International Institute of Tropical Agriculture (IITA), Nigeria; 24 indigenous germplasm collected from different parts of India and four released commercial varieties were evaluated in a randomized block design during Kharif, 2019. The analysis of variance by Panse and Sukhatme (1985), genetic parameters by Burton and De Vane (1953) and heritability in a broad sense and genetic advance by methods given by Allard (1960) and Johnson et al., (1955) were carried out to validate the results. Result: The analysis of variance revealed that genotypes exhibited significant differences for all the characters. Based on per se performances, the exotic collections for flowering and maturity traits and check varieties followed by indigenous collections for yield and yield characters have exhibited superior performance. The highest range of variation was observed for green pod yield per plant. The highest variation was observed for pod yield per plant and number of pods per plant. The higher estimates of GCV and PCV ( greater than 20%) were registered by pod width, mature pod weight, number of pods per plant and pod yield per plant, which indicates partly the interaction of the genotypes with the environment influencing the expression of these characters. High heritability along with high genetic advance was observed for green pod yield per plant, pod length, pod width and number of pods per plant indicating that these traits were mainly governed by additive gene action and responsive for their further improvement. The maximum coefficient of variation was recorded for pod width followed by green pod yield per plant, pod weight and pod length. Green pod yield per plant has a positive and significant correlation with pod length, pod width, mature pod weight, number of pods per plant and number of seeds per pod. Hence, these characters should be considered, while selecting the genotypes for their further genetic improvement in vegetable cowpea.