Evaluation of F4 Generation of Cowpea (Vigna Unguiculata) Genotypes for Drought Tolerance and High Yield

Abstract

Globally, demand for improved agricultural production has increased as a result of an increasing human population. Drought and heat stress brought on by climate change exacerbate the difficulties of increasing crop production. Drought stress has a primary consequence of lowering crop output by reducing biomass and seed weight. Irrigation and breeding are two strategies for minimizing the consequence of drought or addressing the problem of drought stress. Irrigation, on the other hand, necessitates a significant upfront investment and the availability of water throughout the growing season, particularly during flowering and pod filling. This makes it more difficult, particularly for African small-scale farmers. The study was aimed at increasing cowpea yield through improved tolerance to drought. There was high diversity among the genotypes for days to first flowers, chlorophyll content, plant healthiness, stem greenness, number of seeds per pod, number of pods per plant, number of days to maturity, and ultimately the yield of the genotypes across all the treatments applied. The most decline was observed in the pod filling stage drought treatments across all measured parameters. Pearson correlation was conducted to observe the relationships between the parameters measured. The correlation analysis revealed a strong relationship was established between chlorophyll content and plant healthiness. Number of pods per plant was positively correlated to number of seeds per pod and similarly, seed size and pod length, revealing that the size of seeds and number of seeds in a pod determines the length of the pod. The ranking of genotypes based on the three drought tolerant parameters revealed some genotypes that performed better than Danila, a known drought tolerant line and Hewale the high yielding local cultivar. High yielding and drought tolerant genotypes for the vegetative and pod filling stage drought showed true drought tolerance.