Towards a Sustainable Agriculture: Strategies Involving Phytoprotectants against Salt Stress

Salinity is one of the main constraints for agriculture productivity worldwide. This important abiotic stress has worsened in the last 20 years due to the increase in water demands in arid and semi-arid areas. In this context, increasing tolerance of crop plants to salt stress is needed to guarantee future food supply to a growing population. This review compiles knowledge on the use of phytoprotectants of microbial origin (arbuscular mycorrhizal fungi and plant growth-promoting rhizobacteria), osmoprotectants, melatonin, phytohormones and antioxidant metabolism-related compounds as alleviators of salt stress in numerous plant species. Phytoprotectants are discussed in detail, including their nature, applicability, and role in the plant in terms of physiological and phenotype effects. As a result, increased crop yield and crop quality can be achieved, which in turn positively impact food security. Herein, efforts from academic and industrial sectors should focus on defining the treatment conditions and plant-phytoprotectant associations providing higher benefits.