A review on enhancing crop resilience in adverse environmental conditions: Unveiling the action between plant growth-promoting rhizobacteria and crops
Nishtha R. Vaghela, Vivek B. Jotaniya, Sangeeta D. Gohel
Abstract
Many unfavourable environmental factors such as drought, excessive salt, heat, acidity, cold, and biotic stresses, hinder plant development and agricultural productivity. One of the complex networks of microorganisms inhabiting the rhizosphere is plant growth-promoting rhizobacteria (PGPR), which alleviates these stress-induced limitations. To boost plant resilience, PGPR employ a variety of adaptation strategies, including enhanced water uptake, nutrient mobilization, modulation of phytohormones such as indole-3-acetic acid (IAA), gibberellins (GA), and cytokinins, and activation of stress resistance mechanisms through enzymes like 1-aminocyclopropane-1-carboxylate (ACC) deaminase and antioxidant enzymes. This review highlights the positive effects of PGPR on plant growth and development under various stress conditions. Rhizobacteria significantly enhance photosynthesis by preserving chlorophyll content, improving stomatal regulation, and maintaining photosystem efficiency under abiotic stress. Moreover, PGPR promote sustainable farming practices by reducing chemical fertilizer and pesticide dependence through biological nitrogen fixation, phosphate solubilization, and natural biocontrol of phytopathogens. Additionally, this review identifies major research gaps, challenges in field application, and commercialization hurdles that limit the large-scale implementation of PGPR-based technologies. Future research should emphasize strain optimization, bioformulation improvement, and long-term field validation to translate laboratory findings into effective, scalable solutions for climate-resilient and sustainable agriculture.