Molecular Mechanisms and Breeding Strategies for Heat Tolerance in Plants: An Update

Abstract

Heat stress is one of the major environmental stressors that affect growth, metabolism, and plant productivity. Depending on the severity and length of the heat stress, as well as the unique traits of the affected plant species, plants respond to high temperatures in different ways. Crop output is currently greatly impacted by high temperature (HT); hence methods for maintaining high crop plant yields under HT stress are a crucial agricultural objective. To deal with HT conditions, plants have a variety of acclimation, avoidance, and adaptive strategies. To counteract stress-induced biochemical and physiological changes, important tolerance mechanisms that make use of proteins, ion transporters, osmoprotectants, antioxidants, and other elements involved in signaling cascades and transcriptional control are also triggered. For a plant to survive in high temperatures, it needs to possess the capability to detect the HT stimulus, generate and transmit the signal, and initiate the essential physiological and biochemical adjustments. Several studies based on plants’ morphological, physiological, biochemical, and molecular interactions with heat stress are ongoing, and plants are being developed to be HT tolerant through the use of molecular techniques. This chapter highlights strategies being used to improve thermotolerance in plants and reviews the most recent approaches for heat stress tolerance in plant systems.