Types of Biofertilizers

Biofertilizers can be classified based on the microorganisms they contain:

  1. Nitrogen-fixing biofertilizers
    • Rhizobium – used mainly for leguminous crops.
    • Azotobacter – used for crops such as wheat, maize and vegetables.
    • Azospirillum – commonly used for cereals and grasses.
    • Blue-green algae (cyanobacteria) – especially useful in rice cultivation.
  2. Phosphate-solubilizing biofertilizers
    • Contain bacteria or fungi that convert insoluble phosphorus into forms plants can absorb.
    • Examples: Bacillus, Pseudomonas.
  3. Phosphate-mobilizing biofertilizers
    • Mycorrhizal fungi help plants absorb phosphorus and other nutrients from the soil.
  4. Potassium-solubilizing biofertilizers
    • Microorganisms that make potassium available to plants.
  5. Zinc-solubilizing biofertilizers
    • Microorganisms that increase the availability of zinc in soil.