UNDERSTANDING AND MITIGATING THE IMPACTS OF DROUGHT STRESS IN COTTON- A REVIEW

Water scarcity is the most serious abiotic stress restricting plant productivity throughout the world. Losses in crop yield due to drought exceed from losses caused by other environmental factors. In this review article different morphological, physiological and yield attributes of cotton under drought stress, mechanism of drought induced losses and various management strategies to mitigate drought stress have been discussed. Drought stress reduces growth of leaf, stem and root, interferes with leaf water relations, photosynthesis, respiration, reduces water-use efficiency and ultimately yield of cotton. Under water deficit conditions cotton shows various responses to cope with drought stress. The major mechanisms include accumulation of osmoregulators, plant growth regulators and production of heat shock proteins. Different management strategies to alleviate water deficit stress like foliar application of osmolytes, potassium and growth regulators (hormones), various drought responsive genes, proteins at molecular level, screening and breeding programs against drought tolerance and mulching are also discussed in this paper.