Drought Stress Adaptive Responses of Six Short-Cycle Cowpea Varieties Grown in Togo.
Publication Date: 10/09/2025
Author(s): Lamèga Madjonga, Atalaèsso Bokobana, Tchilabalo Ketetche, Yao Dodzi Dagnon, Outéndé Toundou, Damigou Bammite, Koffi Tozo.
Volume/Issue: Volume 8, Issue 2 (2025)
Page No: 139-155
Journal: African Journal of Agriculture and Food Science (AJAFS)
Abstract:
Drought stress is a major hindrance to cowpea cultivation. In Togo, climate fluctuations lead to sudden droughts, posing a real threat for this crop. This survey aimed to evaluate the effects of an induced water deficit in 6 short-cycle cowpea cultivars grown in Togo (Amélassiwa, Ketcheyi, Ketcheyi-Soukpelo, Malgbong-Bomoine, Siéloune, and TVX). The experimental device, under semi-controlled conditions, was a split plot (three repetitions, two treatments) with two interacting factors, varietal type and water regime. Plants in the flower initiation phase were subjected to a water deprivation of 30% of available water content (AWC) for 14 days. Plants used as control were irrigated at 70% of AWC. The fluctuations in growth parameters, total proteins, proline, malondialdehyde (MDA) levels, and yield variables were determined, and the data were analysed through ANOVA, Tukey HSD, and principal component analysis (PCA). The Fisher-Maurer index, or drought susceptibility index (DSI), was used to distinguish drought-tolerant from susceptible varieties. As a result, ANOVA revealed a significant effect (p 0.05). However, a negative correlation between both contents was noted. PCA revealed that varieties that exhibited higher yields were correlated with proline content, while those that showed higher productivity and MDA levels were correlated with protein content. Thus, osmotic adjustments mechanisms are important aspects to target first during variety improvements. According to DSIs and PCA, the six varieties can be divided into three categories: susceptible varieties (Ketcheyi and Amélassiwa), medium-tolerant varieties (Siéloune, Malgbong-Bomoine, and TVX), and high-tolerant varieties (Ketcheyi-Soukpelo).
Keywords:
Cowpea, water deficit, drought stress, DSI, drought tolerance.
