Biofertilizers: A Viable Solution for Sustainable Agriculture
While chemical fertilizers have played a key role in increasing crop yields over the years, their excessive and indiscriminate use has adversely impacted soil health and the environment. The need of the hour is to promote more sustainable agricultural practices that minimize the use of chemical inputs and ensure long-term soil fertility. Biofertilizers provide a cost-effective and eco-friendly alternative that can help address this need.
What are Biofertilizers?
Biofertilizers refer to preparations containing living microorganisms that help crop plants’ uptake of nutrients by increasing their availability in the soil. They typically contain nitrogen-fixing, phosphate-solubilizing or plant growth-promoting microbes like bacteria and fungi that colonize the rhizosphere and interact favorably with plant roots. When applied through seed treatment or soil application, these beneficial microbes boost various soil and plant nutritional processes without any harmful chemicals.
Main Types of Biofertilizers
The main types of biofertilizers available are:
– Nitrogen-fixing biofertilizers: These contain bacteria like Rhizobium, Azotobacter, Azospirillum etc. that can fix atmospheric nitrogen into plant-usable forms through symbiotic or non-symbiotic processes. Legume crops like pulses are major beneficiaries of Rhizobium inoculation.
– Phosphate-solubilizing biofertilizers: Microbes like Pseudomonas and Bacillus present in these formulations aid the solubilization of fixed soil phosphorous, making it accessible to plants.
– Potash-mobilizing biofertilizers: Certain fungal strains secrete organic acids that help release potassium locked in soil micronutrients.
– Zinc-mobilizing and zinc-solubilizing biofertilizers: Microbial inoculants containing Bacillus, Pseudomonas and Aspergillus help overcome deficiency of zinc in alkali soils.
Advantages of Biofertilizers over Chemical Fertilizers
– Eco-friendly: Being microbial inoculants, biofertilizers do not pollute soil and water resources unlike chemical fertilizers.
– Improve soil health: The beneficial microbes improve soil structure and fertility by secreting growth-enhancing substances, making nutrients more bioavailable.
– Increase nutrient uptake: By colonizing plant roots biofertilizers help absorption of major, secondary and micronutrients in a sustained manner compared to surface application of chemicals.
– Reduce production costs: Due to their low application rates and nutrient recycling ability, biofertilizers cut down expenditure on purchase of chemical manures over long-term.
– Boost crop immunity: The plant growth-promoting microbes induce systemic resistance in crops against biotic and abiotic stresses through nutrient synthesis.
Applications of Biofertilizers in Different Crops
Cereals: Seed treatment with azotobacter or azospirillum biofertilizers before sowing wheat, rice, maize etc. saves 20-30% of nitrogenous fertilizers.
Pulses: Inoculation of legume seeds with rhizobium cultures fixes 20-60 kg nitrogen per hectare supporting cultivation of beans, peas and lentils without nitrogen application.
Oilseeds: Soil/seed application of phosphate solubilizing bacillus and pseudomonas in soybean, groundnut and mustard enhances phosphorus availability for better yields.
Plantation crops: Mixing azotobacter/azospirillum with Trichoderma in the ratio of 5:1 helps nutrient/water management in coconut, areca nut, cocoa and cashew orchards.
Commercial Production of Biofertilizers
Biofertilizers find large-scale commercial production by various agencies under strict quality control guidelines of National Project on Development and Use of Biofertilizers. The microbes are mass multiplied on an affordable substrate in controlled fermentation chambers. After ensuring their viability and performance, the products are packed in degradable polyethylene bags and distributed among farmers through a network of authorized dealers.
The urgent need today is to move away from destructive farming methods towards resource-conservation practices. Biofertilizers offer a natural, inexpensive and risk-free solution that aligns perfectly with the goals of sustainable agriculture. Mainstreaming their use especially for small and marginal holdings through policy intervention and availability of quality products can significantly reduce the burden of expensive chemicals on Indian soils and farmers. With proper promotion, biofertilizers hold immense potential to make agriculture more eco-friendly and remunerative in the long run.
Note:
1. Source: Coherent Market Insights, Public sources, Desk research
2. We have leveraged AI tools to mine information and compile it
