Organic Solutes in Cereals Under Abiotic Stress

Abstract

AbstractCereals are the major source of agricultural grain production worldwide. These cereal crops experience various harsh environmental conditions which reduce their growth and productivity. They respond to these stressful conditions by accumulating various types of organic solutes including amino acids and their derivatives (proline, polyamines), quaternary ammonium compounds (glycine betaine), sugars (trehalose, sucrose, fructans), and sugar alcohols (mannitol, inositol). These organic solutes are highly soluble, nontoxic, and low-molecular-weight compounds that stabilize the membrane structures and other cellular components. Further, they maintain the osmotic potential of the cell, act as signaling molecules, and scavenge reactive oxygen species produced due to osmotic stress. Various cereal crops have been reported to accumulate different compatible solutes under abiotic stress conditions which enhanced the stress tolerance. However, some crops cannot synthesize these solutes in an appropriate amount; thus exogenous applications have been used by various researchers. Further, incorporating genes related to biosynthetic pathway enzymes of organic solutes enhanced their accumulation in various transgenic crops. Therefore, this chapter discusses the main categories of organic solutes and their role in ameliorating the stress in crop plants growing under adverse environmental conditions.KeywordsAbiotic stressCerealsOrganic solutesOsmotic stress