biofertilizers

Biofertilizers are preparations containing living microorganisms that, when applied to seeds, plant surfaces, or soil, promote plant growth by increasing the availability of nutrients to the host plant. They are used to supplement or partly replace chemical fertilizers, support sustainable agriculture, and improve soil health. The main functions of biofertilizers include nitrogen fixation, phosphate and potassium solubilization, production of growth-promoting substances, and enhanced soil microbial activity.

Common types include nitrogen-fixing bacteria such as Rhizobium for legumes and Azospirillum or Azotobacter for cereals; phosphate-solubilizing bacteria and fungi, such as Bacillus and Pseudomonas species; potassium-solubilizing microbes; and mycorrhizal fungi that expand the root zone. Plant growth-promoting rhizobacteria, including Bacillus, Pseudomonas, and Bacillus subtilis, may also produce phytohormones, siderophores, and antimicrobial compounds that help control soil-borne pathogens.

Applications include seed treatment, seedling root dipping, and soil inoculation at planting or during crop growth. Benefits observed include improved nutrient uptake, reduced dependence on chemical fertilizers, enhanced soil structure and microbial diversity, and better tolerance to drought or salinity in some crops. Effectiveness varies with crop, soil, climate, and management practices, and biofertilizers should be used as part of an integrated nutrient management plan.

Quality and regulation vary by region. Viability and performance depend on product quality, storage conditions, and proper application. Selecting well-studied strains for the target crop and following label recommendations are important for achieving reliable results.