Role of sugars in regulating physiological and molecular aspects of plants under abiotic stress

Over the last decade, intensive research has been focused on various stimuli that affect the physiology, biochemical constituents, and molecular processes in plants against fluctuating environmental factors. Sugar is a vital molecule which acts as a key regulator to promote growth and development at different stages of the plant. Carbohydrates are essential macromolecule in plants. Hence, sugars are potential signaling molecules in multifaceted metabolic pathways like photosynthesis, carbohydrates metabolism, cellular respiration, and defense responses. Being chemically varied molecule, they act as a central controller to augment adaptation to multifactorial abiotic stresses as sugars are long-distance transporters in plants. Owing to the dynamic metabolic nature of soluble sugar, regulate diverse physiological functions like an energy source for growth, serve as a precursor for metabolic pathways, osmoprotectants on cell dehydration, long-range signaling molecule and modulate reactive oxygen species scavenging system. Recent advancements in the field of molecular biology manifest wide molecular mechanisms underlying the significant role of sugar to modulate the expression of genes that are responsible for plant tolerance against adverse environmental factors. Therefore, in this chapter, we summarize the magnitude of sugar molecules to regulate physiological and molecular processes in plants with abiotic stress.