A Comprehensive Review on the Efficiency of Prokaryotic Rhizobacteria as Biofertilizers

Unsustainable agricultural practices and declining soil fertility have led to a notable reduction in global crop productivity. The excessive and indiscriminate use of chemical fertilizers not only deteriorates soil health but also possess a significant risk to human well-being. Consequently, farmers across the globe have increasingly adopted biofertilizers and biopesticides to preserve the natural equilibrium of the soil ecosystem. Biofertilizers represent an environmentally benign and economically viable alternative to chemical fertilizers. Their plant growth-promoting attributes are manifested through direct mechanisms such as biological nitrogen fixation, nutrient solubilization and mobilization (notably of N, P, K, S, Zn and Fe) and the synthesis of phytohormones including auxins, cytokinins, gibberellins and ethylene. Indirectly, plant growth- promoting rhizobacteria (PGPR) contribute to the suppression of phytopathogens via antibiotic production, siderophore secretion, hydrolytic enzyme activity, and the induction of systemic resistance. In contrast to conventional chemical fertilizers, biofertilizers offer a cost-effective, sustainable, and renewable solution that ensures the long-term preservation of soil fertility and agricultural productivity.