Evaluation of agro-morphological diversity in some segregating lines of cowpea (Vigna un-guiculata L. WALP)

Abstract

A study was conducted to evaluate agro-morphological characteristics of some segregating lines of eight accessions of cowpea (Vigna unguiculata L. Walp.) using seeds from a first cycle generation progenies. Eight cowpea accessions [GH3684₁ (red), GH3684B₄ (mottle brown), GH 3684B₅ (mottle brown), GH3684A₂ (red), GH3684C₂ (red), GHUCO1_BL (black), GH3684_BL, (black) and GH7184_BL (black with spots)] and an out group IT97K-499-35 (white) were culti-vated under field conditions. Twenty three agro-morphological traits were assessed for thirty three lines of cowpea. A dendrogram generated using 23 agro-morphological characters distinguished the cowpea accessions into two lineages, with the out-group being the most diverse. Generally, morphological polymorphism revealed discriminations among the cowpea accessions studied. Seed weight, plant height, number of branches, length of branches, number of leaves, number of peduncles, length of peduncles and number of seeds per pod as well as number of pods per plant differed significantly (p ≤ 0.05) among the cowpea accessions. The evidence showed that there were variations in morphological characteristics expressed by the cowpea ac-cessions and these were segregations in one trait or the other. The cowpea accession GH UCO1BL is possibly a cross between IT97K-499-35 x SARC-LO2. The segregation lines of GH 3684 had the greatest diversity probably due to genotype environment interactions.