Heat Stress in Maize: Understanding the Physiological and Biochemical Impacts

Abstract

Climate change and global warming significantly impact agriculture, particularly maize (Zea mays L.), a crucial global food, feed, and industrial crop. From 2011 to 2020, the global surface temperature rose by 1.09°C compared to the 1850–1900 baseline, with projections suggesting a further increase, potentially reaching 3°C by 2100. This rise in temperature, driven by greenhouse gas emissions, adversely affects maize, especially during heat stress conditions above 35°C, causing irreversible damage to nutrient uptake, chlorophyll content, and biomass accumulation. Heat stress during critical growth stages, particularly the reproductive phase, leads to pollen sterility, poor seed set, and grain abortion, reducing maize yields by an average of 7.4% per degree Celsius rise. Additionally, heat stress increases oxidative stress and disrupts cellular structures, impairing plant growth. Future research should focus on breeding heat-tolerant maize varieties and optimizing agronomic practices. Advanced genomic tools and biotechnological approaches can accelerate the identification and manipulation of genes involved in heat tolerance. Plant growth regulators such as gibberellic acid, abscisic acid, and salicylic acid show promise in enhancing maize resilience by modulating physiological responses and stress adaptation mechanisms. Interdisciplinary collaboration and innovative technologies are essential for developing effective strategies to ensure sustainable maize production in the face of climate change.