KESRI Roufaida, KESRI Rayene2024-10-152024-10-152024-06-10http//localhost:8080/jspui/handle/123456789/12100This study focused on isolating and identifying effective Plant Growth-Promoting Rhizobacteria (PGPR) strains from earthworm castings. Earthworm castings, rich in nutrients and beneficial microbes, were found to be a significant source of PGPR. The isolated PGPR strains demonstrated their ability to solubilize phosphate, calcium, and potassium, produce siderophores and auxin, which are essential for plant growth. The use of PGPR supports sustainable agriculture by reducing the need for chemical fertilizers and pesticides, promoting healthier crops, and minimizing environmental impact. The findings highlight the potential of earthworm castings in sustainable agricultural practices and the importance of leveraging natural interactions between earthworms, beneficial bacteria, and plants. Future research should focus on wider application and long-term field studies to validate the effectiveness of these PGPR strains in diverse agricultural settings. Advanced genomic and biotechnological tools can further optimize PGPR strains, contributing to resilient agricultural systems that meet growing food demands while preserving environmental health. This research represents a significant step towards sustainable and productive farming practices .enPlant Growth-Promoting Rhizobacteria (PGPR) ,Earthworm castings, Nutrient-rich , Phosphate solubilization ,Calcium solubilization, Potassium solubilization ,Siderophores ,Auxin production.Thesis