Induced salinity tolerance by salicylic acid through physiological manipulations

To feed the world's growing population crop production needs to be increased, however, the existence of limiting environmental factors such as salinity stress has limited crop production. Therefore, in these situations, it is necessary to use appropriate strategies to improve crop production per unit area. One practical, simple, and inexpensive solution is using phytohormones as plant growth regulators (PGR) to improve yield performance in saline conditions. The first reports of the use of PGRSs date back to 1930 and now occupy a large volume of the global market (USD 8–9 billion). Salicylic acid (SA) is the one of PGRs which is widely used in the chemical and medical industries as a very important compound. The global SA market was USD 287 million in 2019. The role of SA in the processes of response and tolerance to environmental stresses such as salinity and drought has been shown in many studies. Although SA affects many physiological mechanisms in plants under salinity stress, the exact answer to the question of how SA induces salinity tolerance is not easy. In this chapter, the effect of SA on different plants under saline conditions is investigated and its physiological mechanisms for improving salinity tolerance are discussed.