Microbial Endophytes: A Hidden Plant Resident, Application and Their Role in Abiotic Stress Management in Plants

Abstract

Microbial communities in nature involve complex interactions with several biotic and abiotic components. An endo-symbiotic association is one in which one organism lives within the host plant for at least a part of its life. It is often obligate and does not create visible disease and has been reported to exist for at least 400 million years. Beneficial endophytes promote plant nutrient uptake, host plant growth, reduce disease severity, inhibit plant pathogens and improve tolerance to environmental stresses. Stresses like salinity, alkalinity, drought, global warming, temperature and pollution will increase in prominence and endophytes are predicted to play a significant role and offer eco-friendly techniques to increase productivity under such conditions. There also exists the potential for genetic modification of endophytes to impart additional stress tolerance traits in hosts. The present review discusses the beneficial effect of fungal and bacterial endophytes, emphasizing improving crop productivity under abiotic stress conditions. The review also discusses the various aspects of physiological and molecular mechanisms determining the interaction and stress tolerance, enhancing plant functions and productivity.