Drought stress is one of the most significant abiotic factors limiting agricultural productivity across the world. Increasing climate variability and irregular rainfall patterns have intensified water scarcity in many agricultural regions, adversely affecting crop growth, physiology, and yield. In recent years, beneficial rhizospheric microorganisms known as Plant Growth-Promoting Rhizobacteria (PGPR) have emerged as an effective biological strategy for enhancing plant tolerance to drought stress. PGPR colonize the rhizosphere and promote plant growth through several mechanisms including phytohormone production, nitrogen fixation, phosphate solubilization, and stimulation of antioxidant defense systems. These microorganisms also regulate stress-related metabolic pathways and improve root architecture, enabling plants to absorb water more efficiently under drought conditions. In addition, PGPR possessing ACC deaminase activity helps to reduce stress-induced ethylene accumulation in plants, thereby promoting root growth and stress tolerance. The present study reviews the mechanisms through which PGPR enhance crop tolerance to drought stress and highlight their potential applications in sustainable agriculture. The findings indicate that PGPR-based biofertilizers can significantly improve plant growth, water use efficiency, and crop productivity under water-limited environments.
Publication Date: 2026-05-19