Agronomic responses of selected improved sorghum [Sorghum bicolor (L.) Moench] varieties to scheduled water stress

The 13th sustainable development goal emphasizes urgent action to combat climate change and its impacts; in this context, continuous evaluation of drought tolerance traits in crops with high climate-smart potential is imperative. The agronomic responses of three sorghum varieties (SAMSORG 44, SAMSORG 47, SAMSORG 48) under severe water stress conditions were investigated in a screen house study in 2022 (August–December) as a 3 × 3 factorial experiment in plastic pots arranged in a completely randomized design (CRD) with three replications. Three soil moisture stress levels [well-watered (WW), moderately water-stressed (MWS) and severely water-stressed (SWS) conditions] corresponding to 100, 50 and 25%, respectively, of fractional soil available water (FSAW) determined gravimetrically were imposed at 21 days after sowing (vegetative) and at 50% flowering (reproductive) for 2 weeks. Agronomic (phenological, growth, yield and yield components) parameters measured were not significantly (p < 0.05) influenced by drought stress. There were significant (p < 0.05) interactions between water stress and variety. The three sorghum varieties responded differently (p < 0.05) in terms of FSAW dynamics at both the vegetative and reproductive stages. SAMSORG 44 had a comparatively superior performance, as indicated by its relatively high moisture stress tolerance. These varieties are suggested to be suitable for cultivation under severe drought conditions.