Impact of Abiotic Stresses on Wheat Yield and Strategies for Mitigation: A Comprehensive Review

Climate change is causing various stresses on field crops, potentially threatening global crop production. Wheat, a cool-season crop, is particularly vulnerable to rising temperatures. Several abiotic stresses, including heat, moisture, and nutrient deficiencies, significantly impact wheat yields. Heat stress during the grain-filling period can drastically reduce wheat yields by shortening the growing period due to earlier flowering and maturity. Water stress, especially under rainfed conditions in arid and semi-arid regions, is a major environmental challenge. Reduced irrigation can negatively affect leaf water potential, transpiration rates, stomatal conductance, and photosynthesis, leading to a notable decline in yield attributes, particularly the number of grains per spike. Nutrient stress also contributes to significant reductions in wheat yield. Adequate nitrogen supply can increase the number of grains per spike and plant height, but excessive use of nitrogenous fertilizers can result in excessive vegetative growth, lodging of plants, and increased greenhouse gas emissions. Given the increasing variability in climate and limited water availability, it is crucial to optimize nutrient and water application and improve their efficiency to sustain productivity and ensure food security.