Variations in agromorphological characteristics of IPGRI Cowpea (Vigna unguiculata (L.) Walp.) accessions

Abstract

Cowpea (Vigna unguiculata (L.) Walp.) remains an important crop in the tropics. One of its challenges remains the selection and improvement of genotypes to meet location–specific needs. We studied ten cowpea accessions in Akamkpa and Ikom, Cross River State, Nigeria. Principal component and biplot analyses associated high yield with growth, flowering, pod and seed traits. Seed weight per plot and number of seeds per plot were phenotypically correlated (rp = 0.99, p ≤ 0.01). Number of seeds per plot and number of seeds per pod were genotypically correlated (rg = 1.00, p ≤ 0.01). TVu–980 did not flower at Akamkpa and TVu–1019 did not grow at Ikom. TVu–992, TVu–53, TVu11, TVu–3629 and TVu–980 (only at Ikom) cowpea accessions showed promising agromorphological attributes for possible crop improvement programmes in Ikom and Akamkpa.

Keywords

• cowpea
• genotypic correlation
• multivariate analysis
• phenotypic correlation
• principal component analysis