Drought stress and morphophysiological responses in plants

More than 80% of the world's population is entirely dependent on the food grown on land. Environmental changes like global warming and low precipitation result in low water availability to crops. Drought stress is a severe problem that is causing massive yield and quality reduction due to environmental changes. Crops, when exposed to drought, result in aberration in their morphological, physiological, and biochemical processes. Drought affects yield, growth, reproduction, and development of crops. Drought also reduces chlorophyll content and pigments necessary for photosynthesis. Prolonged closing of stomata leads to CO2 deficiency, which adversely affects photosynthesis. Oxidative stress results in severe damage to plants. Plant induces its defensive mechanism in order to avoid any kind of deadly damage by Reactive Oxygen Species (ROS). Reduction of transpiration and leaf rolling are the basic responses to reduce water loss and combat adverse conditions due to drought. Tolerant plants have adapted themselves by deep root system, leaf rolling, hormonal signaling, and efficient transpiration. The objective of this review is to develop an understanding about the adverse effects caused by drought and various adaptive measures taken up by plants to minimize these adverse effects.