Abstract / Description
Drought stress is one of the most critical abiotic factors limiting sustainable agricultural production globally. It significantly affects plant growth, physiological processes, and crop yields. This study evaluated the drought tolerance of seven yam landraces under varying soil moisture regimes in a greenhouse during the 2024 growing season. A completely randomized design (CRD) with four replications was implemented, utilizing four soil moisture treatments: T1 = 100% FC (control), T2 = 60% FC, T3 = 30% FC, and T4 = 0% FC (halted after saturation at the experiment's commencement). Growth parameters (plant height [PH], leaf number [LN], branch number [BN], internode length [IL], leaf area [LA], biomass), physiological traits (photosynthetic rate [A], transpiration [E], water use efficiency [WUE], intercellular CO2 concentration [Ci], stomal conductance [gs], stomatal density [SD], relative water content [RWC], chlorophyll content [CC], electrolyte leakage [EL], and drought tolerance indices (drought susceptibility index [DSI], drought tolerance index [DTI], and yield index [YI]) were evaluated. Data were analyzed using two-way ANOVA at a 5% significance level. Drought stress significantly reduced growth, physiological performance, and yield across all landraces compared to the control (T1). However, landraces Aha, Ayno, and Duurundufa maintained higher plant height, yield, and biomass under drought stress (T2–T4). Notably, Afri, Gandifa, and Gebsh did not survive under the most severe stress (T4) after three months, showing no measurable height, yield and biomass. Significant differences (p