Short CommuniCation www.landesbioscience.com Plant Signaling & Behavior e26741-1 Short

Drought is a threat to crop productivity worldwide1 and is not restricted to desert regions, since global warming is determining dramatic losses in agricultural yield even at temperate latitudes.2 During water deprivation, plants rapidly modulate a series of physiological responses in order to economize the water use, such as 1) the stimulation of stomata closure through an increase of ABA content, 2) the accumulation of compatible solutes, and 3) the increased expression of aquaporins and vacuolar H+-pyrophosphatases for maintaining cell turgor through osmotic adjustments.3 When drought persists, long-term adjustments of plant physiology are adopted. Ethylene levels reach concentrations that block plant growth, increasing root to shoot ratio, and in the meanwhile, a larger root system is stimulated to increase water adsorption. Despite these adaptation processes, accumulation of ROS can occur, dramatically compromising cell integrity an