Proline Accumulation and its Defensive Role Under Diverse Stress Condition in Plants: An Overview

Adverse environmental conditions impose stress in the plant, like heat, cold, salinity, heavy metal, nutrient, droughtstress; play a very prominent role to limit the plant growth and development. During the exposure of these wide ranges of stresses, plant itself changing or developing at morphological, biochemical or molecular level. During the morphological changes, plant not only reduceduration of life but also reducing plant body skeletons like shortening of plant height, while the adjustment of ion transport, carbon metabolism and synthesis of osmoregulatory compound or compatible moleculeslike proline, glycinebetaine, sorbitol takes place at molecular level.Different kinds of compatible solutes enable to the plant to tolerate abiotic stress. Proline is one the most effective compatible molecule that produces in the wide range of organism including plant under the adverse conditions. A transcriptional characteristic known as up and down regulation of gene expression may be observed during osmotic stress. These changes may be facilitating directly by various stress condition. The up regulation in the plants result,proline accumulation under osmotic stress while down regulation result deterioration process