Endophyte-Mediated Host Stress Tolerance as a Means for Crop Improvement

Abstract

Plants being sessile are continuously exposed to a wide range of biotic and abiotic stresses that exert adverse effect in their growth and development. Various physiological, biochemical, and molecular machineries are employed by the plants to overcome these stresses. Endophytes are mostly the symbiotic fungi and bacteria that reside inside the plant tissue and stimulate plant growth during stress conditions. Endophyte-mediated plant stress tolerance holds significant role in the analysis of plant-microbe interactions. Although still at its infancy, the endophyte-mediated host stress tolerance including drought, salinity, high-temperature stresses, and pathogenic infection has been well described in the recent times. The molecular mechanism governing the endophyte-mediated stress response includes the induction of plant stress genes and regulation of reactive oxygen species. In the present review, we discuss the evidences for bacterial and fungal endophyte-mediated stress tolerance and associated mechanisms. This information from this review will help the scientific community in the development of suitable biotechnological approaches toward usage of endophyte microbes in the improvement of crop yield under multiple stress conditions.