What are biofertilizers? What are the main sources of biological nitrogen fixation? Name two organisms that fix nitrogen symbiotically and two organisms that fix symbiotically.
Biofertilizers are organisms that can bring about soil nutrient enrichment by their biological activity. Sources of biofertilizers: Bacteria, cyanobacteria, and fungi. Biological nitrogen fixation: The conversion of atmospheric nitrogen into nitrogenous compounds through the agency of living organisms is called biological nitrogen fixation. Symbiotically nitrogen-fixing organisms: Rhizobium leguminosarum, Frankia Bacillus radicicola. Free-living/Asymbiotic nitrogen-fixing organisms-Cyanobacteria, Azotobacter.
