Drought and Salinity Stress: An Overlapping Osmotic Resistance

The present scenario sounds an alarm over the increasing global mean temperature that is coupled with reduced water availability. The present review highlights the osmotic changes that occur on account of water deficit under drought and salinity. Reduced water potential ameliorates the tension in the xylem tissue, thus ultimately leading to xylem cavitation and embolism. The sustained deficit leads to the production of increased reactive oxygen species (ROS) that is not comprehended by usual antioxidative defense system. The upregulation of antioxidative system, variation in root architecture, presence of trichomes, and stomatal regulation alleviate the overall water use efficiency (WUE) under drought and saline conditions. These mitigation strategies are coupled with expression of dehydrins and salt overly sensitive genes (SOS) under drought and salinity, respectively, at the molecular level to provide resistance against the same.