Phenotypic Analysis of Pigeon Pea Reveal Genotypic Variability under Different Environmental Interaction

Abstract

Pigeon pea is one of the most important leguminous crop globally. However it is a neglected pulse crops in South Africa in terms of research and production. Most farmers grow local landraces with low yields and there is lack of diverse material. The objective of the study was to determine the presence of genetic diversity among the pigeon pea genotypes using quantitative and qualitative phenotypic traits. The trials were conducted in Mafikeng and Nelspruit in South Africa. The trials were laid out in randomised complete block designs replicated three times. The quantitative and qualitative phenotypic data were recorded according to pigeon pea descriptor list. The phenotypic data were analysed using analysis of variance, Pearson’s correlations, principal component analysis, and biplots constructed using principal coordinate analysis, Shannon weaver diversity indices and frequencies. The results showed highly significant differences among the genotypes based on plant height, pod bearing and seed number per pod meaning there was vast genetic diversity among the genotypes. Seed yield was positively correlated with seed number per pod, seed number per plant and pod weight whereas pod bearing was negatively associated with hundred seed weight meaning improving seed yield will automatically improve other positively correlated traits. Principal component analysis showed five most important PCs contributing to a total variation of 84.7%. The traits that contributed to the most variation to the total variation observed were plant height, pod length, seed yield, pod bearing and days to flowering. The Shannon weaver indices ranged between 0.98 and 1.00 showing the presence of variation among the qualitative traits measured. The clustering grouped genotypes into three clusters with Tumia and ICEAP 00540 being the most diverse. The diverse genotypes can be used as parents for hybridization and development of transgressive segregants in breeding programmes. There was vast presence of genetic diversity among the pigeon pea genotypes evaluated.