Water deficit is the major abiotic factor limiting plant growth and crop productivity around the world. In all agricultural regions, yields of rain-fed crops are periodically reduced by drought, and the severity of the problem may increase due to changing world climatic trends. Water is essential for plant growth and development and affects plant morphology as well as critical physiological functions, the results of which are manifested in poor growth and decreased yield and fiber quality. The effects of water stress depend on the severity and duration of the stress, the genotype of the plant, as well the growth stage at which stress is imposed.
