A bio fertilizer (also bio-fertilizer) is a substance which contains living microorganisms which, when applied to seeds, plant surfaces, or soil, colonize the rhizosphere or the interior of the plant and promotes growth by increasing the supply or availability of primary nutrients to the host plant. Bio-fertilizers add nutrients through the natural processes of nitrogen fixation, solubilizing 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.
Fertilizer a substance which helps to grow plants rapidly and produce fruits flower and vegetable more quantity in proper time, otherwise fertilizer be a compound, which fulfill the needed minerals orelemerts require for the growth of plants and vegetables to produce and products in proper time.
Fertilizer basically three types:
(1) Inorganic fertilizer
(2) Organic fertilizer
(3) Biofertilizer
Biofertilizer are natural fertilizers which are microbial moculants of bacteria, algae, fungi alone or in combination and they augment the availability of nutrients to the plants. Rhizobium is the best known biofertilizer which fixes atmospher nitrogen symbiotically with legumes. Other bio-fertilizers are Azobacter, Azospirillum, Blue green algae and Azolla.