ABSTRACT
Salicylic acid (SA) is a phytohormone increasingly recognized as an abiotic stress-tolerance enhancer, via SA-mediated control of major plant-metabolic processes; its exogenous application is an emerging tool in plant-drought tolerance. Drought stress results in the increased generation of reactive oxygen species (ROS) due to energy accumulation, which increases the photooxidative effect. General responses to stress involve the signaling stress detection and, consequently, the increase in antioxidant responses. The immunodetection of phytohormones has been proven to be an efficient tool to understand the hormone translocation in plants subjected to different stress situations and to clarify their role in regulating physiological responses. Salicylic acid improves adaptative responses to drought by the direct and/or indirect modulation of several molecular, biochemical and physiological processes, including a better balance between ROS production and scavenging, reducing the oxidative stress. The application of SA also contributes to a reduction in the investment in extra repair damages, while accelerating the restauration of the physiological functions, after stress relief.
