Explain about the Biofertilizers

Biofertilizers, are the cultures of microorganisms used for inoculating seed or soil or both under ideal conditions to increase the availability of plant nutrients. Their purpose is to supplement chemical fertilizers and not to replace them. Some of the microorganisms fix nitrogen to be supplied to crops, convert insoluble phosphates to soluble forms to make them available to crops, synthesise biomass for manuring crops, particularly rice, and hasten the process of decomposition of cellulose in composts and farmyard manures. If these specific organisms are not present in the soil or in the decomposing substrate, they have to be in oculated into the medium to initiate and accelerate biological activity.