Plant Growth-Promoting Rhizobacteria (PGPR): Perspective in Agriculture Under Biotic and Abiotic Stress

Abstract

Knowledge of rhizosphere ecology and its impact on plant physiology has dramatically changed traditional agricultural practices, especially in the context of plant defense mechanisms against biotic and abiotic stresses. It is a universally accepted fact that certain rhizosphere-associated strains, referred to as plant growth-promoting rhizobacteria (PGPR), stimulate plant growth and fitness. Since PGPR in symbiotic interactions are an integral part of the living ecosystem, they are believed to be the natural partners that modulate local and systemic mechanisms in plants to offer defense under adverse external conditions. PGPR producing secondary compounds that may act as signals—that is, allelochemicals—induce plant immunity against pathogen attack. Moreover, multifaceted role of PGPR is now being widely implemented for mitigating abiotic stress caused and induced by climate alternations and for restoring natural soil against variety of toxic metals. Future research demands interdisciplinary research that may pave the significant role of PGPR in modulating/introducing new crop traits under adverse conditions. © 2018 Elsevier B.V. All rights reserved.