Promoting Plant Growth A class of bacteria known as rhizobacteria (PGPR) inhabits the rhizosphere, the area of soil that surrounds plant roots. Through a variety of ways, these bacteria interact positively with plants to promote their growth. Genera including *Azospirillum*, *Bacillus*, *Pseudomonas*, and *Rhizobium* are included in PGPR. Plant science and agriculture both benefit greatly from PGPR. The ability of PGPR to fix atmospheric nitrogen and make it available to plants is one of its main advantages. This mechanism is particularly important for legumes, because symbiotic bacteria, such as *Rhizobium*, grow nodules on the roots of these plants and use the nitrogen gas to produce ammonia, which the plant may use.

Furthermore, phytohormones like auxins, gibberellins, and cytokinins are produced by PGPR and directly stimulate plant growth through increased vigor, seed germination, and root elongation. In addition, certain PGPR generate siderophores—compounds that bind and solubilize iron in the soil, increasing plant accessibility and promoting plant metabolism. Plant defense against pathogens is another important function of PGPR. By creating systemic resistance in plants and generating antimicrobial chemicals, they strengthen the plants’ natural defenses. Because of its capacity for biocontrol, less chemical pesticides are needed, which supports sustainable farming methods.

Additionally, PGPR can enhance fertility and soil structure. They improve soil aggregation and water retention by producing exopolysaccharides and other biofilms, which results in healthier soil ecosystems. In conclusion, PGPR are essential partners in sustainable agriculture, enhancing soil health, plant growth, nutrient availability, and disease resistance. By using them, agricultural systems can become more resilient, crop yields can rise, and chemical inputs can decrease.