Impact of Heat Stress on Phenological, Physiological, Biochemical Processes, Yield, and Mitigation Strategies on Groundnut

Groundnut (Arachis hypogaea L.) is a significant oilseed crop cultivated in several tropical and semi-arid regions. It significantly contributes to global food security, nutrition, and rural livelihoods. Climate warming is raising temperatures, posing a significant threat to productivity and quality. Groundnut development is adversely impacted by thermal stress, particularly when temperatures above 35°C. This is particularly applicable during essential phenological stages such as flowering and pegging. This review examines the impact of heat stress on groundnut phenology, physiological and biochemical processes, yield, and seed quality, along with potential mitigation strategies. Heat stress disrupts critical physiological processes like photosynthesis, respiration, and membrane integrity, and induces oxidative stress through the excessive generation of reactive oxygen species (ROS). These effects diminish pollen viability, exacerbate peg formation, hinder pod development, and result in significant production losses. Heat stress alters seed quality by affecting oil content, fatty acid composition, and protein levels, hence increasing susceptibility to aflatoxin contamination. The article discusses molecular reactions, including the role of heat-responsive genes, heat shock proteins, and transcription factors in aiding organisms' adaptation to stress. The work discusses many strategies to mitigate the impacts of heat, including agronomic techniques, breeding heat-resistant plants, employing biotechnology, and utilizing external protective agents. To develop groundnut production systems capable of adapting to climate change, it is essential to understand their mechanisms.