What would be probable reasons for not getting response from the application of biofertilizers?

1. On account of quality of product
   • Use of ineffective strain.
   • Insufficient population of microorganisms.
   • High level of contaminants.
2. On account of inadequate storage facilities
• May have been exposed to high temperature.
• May have been stored in hostile conditions.
3. On account of usage
• Not used by recommended method in appropriate doses.
• Poor quality adhesive.
• Used with strong doses of plant protection chemicals.
4. On account of soil and environment
• High soil temperature or low soil moisture.
• Acidity or alkalinity in soil.
• Poor availability of phosphorous and molybdenum.
• Presence of high native population or presence of bacteriophages.