Effect of Water Stress (Drought and Waterlogging) on Medicinal Plants

Abstract

Climate change causes different biotic and abiotic stresses to the plants, water stress being one of them. Water stress includes water-logging (flooding) and water deficit (drought). These stresses restrict the plant’s growth, development, and ultimately yield. Approximately 60% of crops, including plants of medicinal importance, are affected by water stress. Water stresses cause physiological disturbance (closure of stomata, decrease in photosynthesis and transpiration) and biochemical alteration (protein denaturing, ROS production, increase in antioxidant enzymes and osmoprotectants) in plants. Water stress can alter the yield of secondary metabolites in medicinal plants. To cope with these stresses, tolerant genotypes have been produced, but more efforts are required for modification of medicinal plant genomes that can help us maintain plant growth and increase yield to meet the requirements of an increasing world population. This chapter deals with the physiological and molecular mechanisms of medicinal plants under waterlogging and water-deficit conditions.