Define biofertilizers. Give an account of technology involved for the mass production of different biofertilizers, with their application.
In short
Biofertilizers are products containing living microorganisms that colonise the rhizosphere and raise nutrient availability by fixing nitrogen or solubilising phosphorus. Mass production involves selecting efficient strains such as Rhizobium, culturing them in fermenters and formulating them on carriers like lignite or as liquid inoculants for seed or soil application.
Model answer
Ghissu Editorial · Verified 4 Oct 2026 · 246 words
Microbial Inoculants
Biofertilizers include Rhizobium, Azotobacter, and Mycorrhiza that fix nitrogen, solubilize phosphorus, and mobilize nutrients, enhancing yields and reducing chemical inputs.
Distinct from Organic Fertilizers
They are carrier-based microbial products, not decomposed organic matter, crucial for soil health in drought-prone Rayalaseema.
Strain Cultivation and Formulation
Selected microbes are cultured in nutrient media and mixed with carriers like lignite or formulated as liquid inoculants with protectants, improving shelf life up to one year and easing storage problems.
Quality Control and Infrastructure
Maintaining microbial viability is key; India’s 537 production units, including those in Andhra Pradesh, ensure quality and cater to local crop needs.
Nitrogen Fixers and Phosphorus Solubilizers
Rhizobium for pulses, Azospirillum for cereals, and Bacillus for phosphorus solubilization support crops like paddy and sugarcane in coastal Andhra Pradesh.
Mycorrhizal and Micronutrient Mobilizers
Mycorrhizae enhance nutrient uptake in horticulture (Chittoor district), while bacteria mobilize potassium and zinc in Rayalaseema.
Regional Mother Culture Facilities
Establish centers in Andhra Pradesh for authentic strains.
Farmer Training
Expand extension and demonstrations via agricultural universities and Krishi Vigyan Kendras.
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