Heat-Induced Oxidative Stress in Plants

Abstract

The United Nations has projected that the population across the globe would grow to 9.1 billion by 2050 at a rate of 34% from as-of-today 6.8 billion. To meet the food demand of the increasing population across the globe, it is important to increase the sustainable crop productivity under the changing climate conditions. Recently, the Intergovernmental Panel on Climate Change reported that abiotic stresses such as heat, salinity, water-logging, drought, heavy metals, cold, and ultraviolet rays are increasing day by day due to the rise of global warming and climate change, which have become the greatest threats to crop production. Among the abiotic stresses, heat stress is considered as the greatest threat for sustainable agriculture and global food security, as heat stress alters the modulation of gene expressions and physiological and metabolic activities, and damages photosynthetic machinery and metabolic pathways, by creating oxidative stress that leads to breaking the DNA/RNA bases, molecules of amino acid, fatty acid, carbohydrate’s products, ultimately leaving the plant growth stunted. Moreover, phytohormones such as melatonin, brassinosteroids, abscisic acid, salicylic acid, jasmonic acid, etc. and a small molecule compound of calcium, nitric oxide, etc. have been experimentally evidenced to mitigate/alleviate/lessen (or protect) the heat stress–induced oxidative stress in plants. At the same time, during heat-induced oxidative stress, tolerant plants can create a signalling pathway by activating downstream genes to produce much protein to survive under heat stress. In such ways, plants try to survive during adverse environmental conditions. In the present chapter, the discussion is focused on deleterious effects of heat-induced oxidative stress in plants, plants self-survivability, and exogenous antioxidants like melatonin, brassinosteroids, etc. to protect plants under heat stress–induced oxidative stress.