Genotype X Trait Bi-Plot Analysis for Assessing Character Association in Cowpea (Vigna Unguiculata L. Walp)

I. Adedeji, A. T. Ajayi, O.S. Osekita, K. L. Ogunruku
2020 South Asian Research Journal of Biology and Applied Biosciences  
Nigeria's restricted data on trait associations in cowpea genotypes has required setting up a study in this region to better understand the interactions between cowpea characteristics. The objectives of this study were therefore to assess the level of genetic variability and inter-character association among accessions of cowpea. Eight selected accessions from IITA were evaluated in the field in a Randomized Completely Block Design (RCBD) with three replications between September and December,
more » ... 018. Each replicate comprised eight accessions in plots of 5 m x 1 m dimension each; accessions were sown at 30 cm intra and 50 cm inter row spacing with 1 m separation between the accessions. Sixteen (16) quantitative traits were evaluated using five plants per accession per replicate. Significant differences were observed among accessions for most studied traits. Phenotypic variance was higher than genotypic variance for traits evaluated. High broad sense heritability and genetic advance as percent of mean were observed for emergence percentage, seeds per pod, seed weight; the seeds per plant had positive correlation with pod per plant and seed yield, indicating that selection for these will result in increase in yield. PCs 1 and 2 (with eigen value >1) accounted for more than 75.63% of the total variations among accessions. Different patterns of associations and genotype (accession) by trait interactions were observed. The genotype x trait bi-plots consistently indicated that seed yield had positive associations with most of the traits; especially peduncles per plant, seeds per plant, terminal leaflet length and terminal leaflet width.
doi:10.36346/sarjbab.2020.v02i01.002 fatcat:hyw72z7jnbfvfkeeu47xze6phq