Plant Metabolism during Water Deficit Stress: A Review

Water deficit stress is one of the chief abiotic stresses adversely affecting plant endurance leading serious effects on plant metabolism. Depending upon strength and duration of water deficit conditions, plants adjust a series of physiological, cellular and molecular mechanisms aiming a correct stress response. Some of the responses of plants to water stress include decreased growth and development and hence decrease in fresh biomass, decreased content of chlorophyll and hence the decreased rate of photosynthesis, decrease in leaf relative water content (RWC) and increased accumulation of osmolytes like proline, sucrose, soluble carbohydrates, etc. Several enzymes involved in carbohydrate metabolism seem to play a role in the multi-layered response of plants to water deficiency. Glycolysis is a central metabolic pathway that provide elasticity when production of energy for existence is confronted and is modulated to establish a novel homeostasis under stress conditions in plants. Evidence for the participation of glycolytic genes, proteins and enzymes in response to stress is established by the fact that their expression is deeply affected by exposure of plant tissues to environmental stresses such as drought. Keeping in mind the importance of glycolytic pathway during stress conditions in plants, the impact of the drought stress on plant glycolysis is the subject of current review. In addition, plant physiology and carbohydrate metabolism under drought stress are also discussed.