Biofertilizers are Preparations containing live or latent cells of efficient strains of nitrogen fixing, phosphate solubilizing or cellulolytic microorganisms used for application to seed, soil or composting areas.
A simple form of classification of biofertilizers is given below:
I) For Nitrogen
· Rhizobium for legume crops.
· Azotobacter l Azospirillum for non legume crops.
· Acetobacter for sugarcane only.
· Blue -Green Algae (BGA) and Azolla for low land paddy.
2) For Phosphorous
· Phosphatika for all crops to be applied with Rhizobium, Azotobacter,Acetobacter.
· VAM(Vesicular-arbuscular mycorrhiza).
3) For Enriched Compost
· Cellulolytic fungal culture.
· Phosphotika and Azotobacter culture.
Basic Advantages of Biofertilizers
- Increase availability or uptake of nutrients through solubilization or increased absorption.
- Stimulate plant growth through hormonal or antibiotics action or by decomposing organic waste.
- They are cheap, hence, reduced cost of cultivation.
- Improves soil properties and sustaining to maintain soil fertility.
- Lead to soil enrichment.
- Are compatible with long term sustainability.
- Build up soil fertility in the long term.
- They are eco-friendly and pose no damage to the environment and soil.
Disadvantages of Biofertilizers
- Specific to the plants.
- Rhizobiurn spp. culture doesn't work well in high nitrate tolerant strains of soybean.
- The acceptability of biofertilizers has been rather low chiefly because they do not produce quick and spectacular responses.
- Require skill in production and application.
- Difficult to store.
