ABSTRACT
The accumulation of osmolyte (compatible solutes) in response to various stresses is a widely distributed phenomenon in the plant kingdom and regarded as a basic strategy for the protection and survival of plants under abiotic stress by lowering water potential without decreasing actual water contents, which leads to osmotic adjustment. They are non-toxic and are accumulate to significant levels without disrupting plant metabolism. Understanding the metabolism, transport and physiological roles of the osmoprotectants during stress is vital in developing plants for stress tolerance. There is an urgent need to identify the signaling components related to the osmolytes biosynthesis and degradation and their coordination in gene expression events under stress and at recovery. These metabolites accumulate under stress and can maintain turgor pressure, protect macromolecules of cells from the damaging effects of ROS, protect cell membranes against oxidation, stabilize proteins, enzymes and cell structures and act as antioxidants, thermo stabilizers or scavengers that help plants to avoid and/or tolerate stresses.
