Plant Growth-Promoting Rhizobacteria (PGPR) have emerged as vital components of sustainable crop protection strategies, offering an eco-friendly alternative to synthetic agrochemicals. These beneficial microorganisms colonize the rhizosphere and suppress a wide range of phytopathogens through diverse mechanisms including the production of antimicrobial compounds, competition for nutrients and ecological niches, degradation of virulence factors, and induction of systemic resistance in host plants. PGPR not only promote plant health but also contribute to improved soil fertility and ecological balance. This chapter comprehensively explores the multifaceted roles of PGPR in suppressing bacterial, fungal, and nematode pathogens, with emphasis on recent advances in molecular insights, formulation technologies, and successful integration into farming practices. Challenges such as variability in field efficacy, formulation stability, and regulatory hurdles are discussed alongside emerging solutions and future directions for large-scale commercialization. Overall, PGPR represent a cornerstone of the transition toward climate-resilient, low-input, and biologically-integrated agriculture.
Plant growth-promoting rhizobacteria, Biocontrol, Induced systemic resistance, Rhizosphere, Sustainable agriculture
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