PGPR-Mediated Defense Priming: A Sustainable Paradigm for Combating Biotic and Abiotic Stresses in Agriculture

Abstract

In the face of complex biotic and abiotic stresses, modern agriculture seeks innovative solutions to ensure sustainable crop production. Plant Growth-Promoting Rhizobacteria (PGPR) emerges as powerful allies, offering a sustainable approach to fortifying plant defense mechanisms. This review delves into harnessing PGPR-mediated defense priming to combat both biotic and abiotic stresses in agriculture. Defense priming, a sophisticated mechanism acquired through exposure to primary stimuli, empowers plants to mount quicker and more resilient defense responses against subsequent challenges. PGPR induce a pre-conditioned state of heightened alertness, enabling rapid and robust defense responses upon stress encounters. This paradigm not only enhances plant resilience to pathogens and environmental stressors but also promotes sustainable practices by reducing chemical inputs. The review critically evaluates the mechanisms underlying PGPR-mediated priming, emphasizing its potential to modulate plant physiology, metabolite production, increased antioxidants enzymes, defense related enzymes activities and enhance stress tolerance. It further explores how PGPR can improve plant responses to a spectrum of stressors. This review also highlights PGPR-mediated defense priming as a cost-effective, enduring, chemical-free, and sustainable method for managing abiotic and biotic stresses in agriculture. Implementing this strategy offers effective crop protection with minimal fitness and environmental costs, even in harsh conditions.