Give a short account of biofertilizers.

Biofertilizers - Organisms which enrich the soil with nutrients are called biofertilizers. Biofertilizers are used for the specific crop plants such as pulses, legumes, oil seeds and rice. They are renewable and non-pollutant sources of plant nutrient such as nitrogen.They do not cause pollution.

Nitrogen fixing microorganisms, i.e., non-symbiotic and symbiotic cyanobacteria and phosphate-solubilising microorganism are the main type of biofertilizers.