Variability, correlation and path analysis studies in F2 generation of cowpea [Vigna unguiculata (L.) Walp]

Abstract

Cowpea Vigna unguiculata (L.) Walp is one of the most important food and forage legumes in the semi-arid tropics due to its drought tolerance and ability to grow on poor quality soils. As a self pollinated crop and existing variability is insufficient for further crop improvement. Two genetically diverse parents were crossed (C-152 × V-16) and advanced to F2 generation. The magnitude of variation, heritability, genetic advance, association of component characters and path co efficient analysis were estimated in a set of 194 F2 individuals. Grain yield is complex and is determined by several component traits. The traits having high heritability and significant positive correlation with the grain yield can be utilized for indirect selection for genetic improvement. Results revealed that a high PCV and GCV, Heritability in broad sense and generic advance as per cent of mean were recorded for plant height, 100- seeds weight and seed yield per plant. Moderate PCV and GCV were noticed in branches per plant and pods per plant. Seed yield per plant exhibited significant positive association with plant height (0.132), number of branches per plant (0.143) and pods per plant (0.123). Highest positive direct effect was on number of branches per plant (0.168), seeds per pod (0.158), pods per plant (0.115) and 100 seeds weight (0.102). Information obtained in this study suggests that traits like plant height, number of branches per plant, number of pods per plant, 100-seeds weight could be used as selection criteria for grain yield improvement at segregating populations of cowpea.