Plant Hormones as Key Regulators in Plant-Microbe Interactions Under Salt Stress

Abstract

Salinity is a global problem that hinders the normal growth and development of most plants. The loss of arable land due to salinization directly affects the food requirements of the world’s population. However, plants have their own tolerance mechanisms that can help to withstand a certain degree of salinity. Nonetheless, plants often fail to survive under high saline conditions. Many published studies have advocated the positive influence of phytohormones on the growth and stress tolerance of plants. In addition, the microbes associated with plants have the capability to synthesize plant growth hormones that play an important role in alleviating salt stress in plants. The biosynthesis of phytohormones such as auxins, gibberellic acid, salicylic acid, and abscisic acid by root-associated microbes is a compelling mechanism to alter plant physiology and the biochemical processes in plant tissue. This review summarizes the plant phytohormones and their metabolism and activity under abiotic stress. In addition, it addresses the microbes that produce phytohormones that are closely associated with plants, along with their roles and interactions with plants under various stress conditions.