• harnesses atmospheric nitrogen and makes it
available directly to the plants.
• increases phosphorus uptake by solubilising and
releasing unavailable phosphorus.
• enhances root proliferation due to release of
growth promoting harmones.
• increases the crop yields by 10 – 25 %.
• improves soil properties and sustain soil
• are cost effective and environment friendly.
• benefit to cost ratio of biofertilizers is fairly
1. On account of quality of product
o Use of ineffective strain.
o Insufficient population of microorganisms.
o High level of contaminants.
2. On account of inadequate storage facilities
o May have been exposed to high temperature.
o May have been stored in hostile conditions.
3. On account of usage
o Not used by recommended method in appropriate doses.
o Poor quality adhesive.
o Used with strong doses of plant protection
4. On account of soil and environment
o High soil temperature or low soil moisture.
o Acidity or alkalinity in soil.
o Poor availability of phosphorous and molybdenum.
o Presence of high native population or presence of
biofertilizers make up by many algal plant and angiosperm
and some decay leaves contain organic mater. It is
decomposed. to useful compound by some earth worm . and also
symbiotic association with azolla anabena the are fix the
nitrogen in earth and gives the nitrogen to the host plant.
disadvantages for that compost more number of cost
Decrease the use of costly chemical fertilizers.
It is pollution free.
Supply plant nutrients (N & P)
Secrete plant growth hormones.
Protect from pathogens.
Less costly & simple to use.
It is renewable.
Increases soil fertility.
Non-toxic to non-target organism.
Very specific to target plant.
Bio fertilizers require special care for long-term storage because they are alive. They must be used before their expiration date. If other microorganisms contaminate the carrier medium or if growers use the wrong strain, they are not as effective. The soil must contain adequate nutrients for bio fertilizer organisms to thrive and work. Bio fertilizers complement other fertilizers, but they cannot totally replace them. Bio fertilizers lose their effectiveness if the soil is too hot or dry. Excessively acidic or alkaline soils also hamper successful growth of the beneficial microorganisms; moreover, they are less effective if the soil contains an excess of their natural microbiological enemies. Shortages of particular strains of microorganisms or of the best growing medium reduce the availability of some bio fertilizers.