Genetic variability, correlation and path analysis in cowpea [Vigna unguiculata (L.) walp]

Cowpea [Vigna unguiculata (L.) Walp] is a self pollinated crop, belonging to family fabaceae and sub family papilionaceae. It is an important multipurpose grain legume extensively cultivated in arid and semi arid regions of Sub-Saharan Africa, Asia, Central and South America. The assessment of variability present in any crop species is an essential pre requisite for formulating an effective breeding programme, as the existing variability can be used to enhance the yield level of cultivars after following appropriate breeding strategies.

The present investigation was carried out during the Kharif season of the year 2019. The field experiment was carried out at Pulses Research Station, NAU, Navsari in randomized block design. The study was undertaken on fifty three genotypes of cowpea to know the variability present among genotypes for thirteen traits and correlation and path analysis of yield components.

Analysis of variance indicated significant genotypic differences for all the characters under study. The highest GCV was recorded for plant height, pods per plant, pods per cluster, seed yield per plant, straw yield per plant, 100 seed weight and harvest index. High heritability coupled with high genetic advance was exhibited by days to 50 per cent flowering, days to maturity, plant weight, seed yield per plant, 100 seed weight, pod length, pods per cluster and seeds per pod indicating the presence of additive gene action. Seed yield per plant was found to be positively and significantly correlated with pods per plant, pods per cluster, pod length, days to 50 per cent flowering and straw yield per plant or seed yield per plant. The present study has indicated the need for giving due weightage to pods per plant, pods per cluster, seeds per pod, 100 seed weight, pod length with straw yield per plant for improving seed yield in cowpea.