Question

Which of the following symbiotic association is useful as biofertilizer?

• A. Rhizobium and leguminous roots
• B. Azolla and Anabaena
• C. Both A and B
  
• D. None of the above
  

Answer 1

The correct option is C Both A and B

Biofertilizers are organisms that enrich the nutrient quality of soil. The main sources of biofertilizers are bacteria, fungi, and cynobacteria (blue-green algae). The most striking relationship that these have with plants is symbiosis, in which the partners derive benefits from each other. Plants have a number of relationships with fungi, bacteria, and algae, the most common of which are with mycorrhiza, rhizobium, and cyanophyceae. These are known to deliver a number of benefits including plant nutrition, disease resistance, and tolerance to adverse soil and climatic conditions. These techniques have proved to be successful biofertilizers, that form a healthy relationship with the roots. Examples of symbiotic association used as a biofertilizers are Rhizobium and leguminous roots, Azolla and Anabaena etc.