Genetic Divergence in Cowpea (Vigna unguiculata L. Walp) - an Overview

Authors : Ravish Panchta, Rajesh Kumar Arya, Nguyen Nagoc Vu, Rishi Kumar Behl

Pages : 1-20

View : 27 | Download : 9

Publication Date : 2021-01-01

Article Type : Research

Abstract :Cowpea [Vigna unguiculata L.Walp] is an important summer/rainy season legume crop which is tolerant to drought as well as water logging conditions. It provides nutritious grain and an inexpensive source of protein. In cowpea breeding programmes, the major emphasis has been on the collection and conservation of genetic pools. The knowledge on the nature and extent of genetic variability present in any crop species plays an important role in designing a suitable breeding method. Genetic diversity is the foremos t basic requirement for a successful breeding programme. Heritability is a biostatistic commonly used in plant breeding and genetics works that estimates how much variation in a phenotypic trait in a population is due to genetic variation among individual plants in that population. Genetic advance is the improvement in the mean genotypic value of selected plant families over that of base population. It depends upon phenotypic variability, heritability and intensity of selection. The evaluation of cowpea germplasm, quantification of the magnitude of variability existing for different characters and classification into groups help in identifying potential distinct genotypes which are having contrasting characters, can be used to operate effective selection of genetically diverse genotypes for the improvement of yield. In this review paper, the research work carried on different aspects of genetic divergence is discussed under the sub-heads, i.e. variation of qualitative and quantitative traits, genetic variability, heritability and genetic advance, correlation and path analysis, genetic divergence using D2 analysis and genetic diversity by using molecular markers.
Keywords : Cowpea, genetic variability and divergence, heritability, genetic advance