Effects of Drought and Heat Stress on Morphophysiological Traits of Sorghum ( Sorghum bicolor [L.] Moench)

Sorghum is a climate‐smart cereal crop inherently adapted to drought and heat stress, playing a vital role in ensuring global food and nutritional security. Despite its inherent tolerance to drought and heat stress, sorghum production is increasingly challenged by climate‐driven stresses that impair critical morphophysiological processes and reduce yield stability. Drought and heat stress are among the most serious constraints to global food security, significantly limiting crop productivity and exacerbating vulnerability in already food‐insecure regions under the intensifying impacts of climate change. Drought limits sorghum growth and biomass by reducing cell expansion, whereas heat accelerates development and leaf senescence, together shortening grain filling and decreasing yield. Drought and heat stresses frequently co‐occur in sorghum, leading to leaf rolling, leaf firing, and premature senescence, which significantly reduce yield. While drought promotes deeper and more extensive root growth to enhance water uptake, heat stress negatively affects root growth and function. Physiologically, drought limits photosynthesis through stomatal closure and reduced carbon assimilation, whereas heat stress impairs photosystem II, enhances photorespiration, and disrupts thylakoid membrane stability, collectively lowering photosynthetic efficiency. Both stresses reduce chlorophyll content, relative water content, and water‐use efficiency, while increasing respiration rates and canopy temperature, leading to excessive carbohydrate depletion and restricted assimilate translocation to developing grains. At the cellular level, membrane integrity declines due to enhanced lipid peroxidation, resulting in increased electrolyte leakage and oxidative damage. Therefore, sorghum’s adaptive traits, such as deep rooting, efficient stomatal regulation, osmotic adjustment, robust antioxidant defenses, thick cuticles, and the stay‐green phenotype, can be leveraged through integrated conventional and biotechnological breeding to develop climate‐resilient, high‐yielding, and nutrient‐rich cultivars, thereby promoting sustainable food systems and contributing to SDG‐2 (Zero Hunger) and SDG‐13 (Climate Action) under increasingly frequent drought and heat stresses.