Soil is the prime source of essential nutrients to plants. Unavailability of a nutrient to the plant show deficiency symptoms, which result in yield decline.
Rhizospheric bacteria has got a vital role in the geochemical cycling of nutrients like nitrogen, phosphorus and micronutrients like iron, manganese, zinc and copper. These micro-organisms determine the nutrient availability for plants and also for soil microbial community.
These bacteria helps in enhancing crop yield by increasing plant nutrient availability, producing growth hormones and they also acts as a bio agent for control of many plant parasitic pathogens.
In present agricultural scenario nutrients availability in the soil has declined due to indiscriminate use of inorganic nutrients’ sources without giving any importance to soil microorganisms.
The nutrient use efficiency can be enhanced by adding biofertilisers to the rhizosphere environment or root zone or agricultural soil.
What is bio-fertilizer?
A bio-fertilizer is a living microorganism substance which, colonizes in the soil rhizosphere or in the interior parts of the plant and promotes growth by increasing the supply or availability of primary nutrients to the plant.
These bio-fertilizers add nutrients through the natural processes of nitrogen fixation, solubilising phosphorus, and stimulating plant growth through the synthesis of growth promoting substances.
Bio-fertilizers can be expected to reduce the use of chemical fertilizers and pesticides.
The microorganisms in bio-fertilizers restore the soil’s natural nutrient cycle and build soil organic matter.
Why use bio-fertilizers?
- Bio-fertilizers may be a safe alternative to chemical fertilizers to minimize the soil ecological disturbance.
- They may increase crop yield upto 10-40% and fix nitrogen upto 40-50 kg.
- They improve soil texture, pH, and other properties of soil.
- They produces plant growth promoting substances IAA amino acids, vitamins etc.
Types of Biofertilisers
- Nitrogen fixing Biofertilisers - Rhizobia are used for legume crops, Azotobacter or Azospirillum for non-legume crops, Acetobacter for sugarcane and blue-green algae and Azolla for lowland rice paddies.
- Phosphorous solubilising and mobilizing Biofertilisers, - Bacillus megaterium, some Pseudomonas spp bacteria, Aspergillus species and Vesicular Arbuscular Mycorrhizal (VAM) fungi
Potassium mobilizing biofertilisers – Frateuria aurentia
Zinc mobilizing biofertilisers – Some Bacillus bacteria species
Sulphur mobilizing biofertilisers - Some Bacillus bacteria species
Method of application of Bio fertilisers.
- Seed treatment: Mix 25 – 50 g of Biofertilisers [Powder formulation] 5 to10 mL /L [Liquid formulation] per litre of cow dung slurry for treatment of 1kg of seed before sowing, particularly for cereals, pulses and oilseeds.
- Nursery treatment: Drench nursery beds with @ 15 gm Biofertilisers [Powder formulation] 5 mL /L [Liquid formulation] per litre of water before sowing.
- Cutting and seedling root dip: Mix 25 – 50 g of Biofertilisers [Powder formulation] 3 to 5 mL /L [Liquid formulation] per litre of water and dip the cuttings and seedlings for 20-30 minutes before planting.
- Soil treatment: Mix 5 to 10 kg of Biofertilisers [Powder formulation] 2 to 3 L [Liquid formulation] in 100 kg of farmyard manure and cover it for 7 days with polythene. Mix the mixture in every 3-4 days interval before broadcasting in the field.
K SANJEEVA REDDY,
Senior Agronomist, BigHaat.
Disclaimer: The performance of the product (s) is subject to usage as per manufacturer guidelines. Read enclosed leaflet of the product(s) carefully before use. The use of this product(s)/ information is at the discretion of user.