Question

Biofertilizer include

• A. nitrogen fixing bacteria
• B. nitrogen fixing cyanobacteria
• C. both bacteria and cyanobacteria
• D. bacteria, cyanobacteria and mycorrhizal fungi

Answer 1

The correct option is D

bacteria, cyanobacteria and mycorrhizal fungi

The Correct option is: D

Explanation of the correct option:

1. Biofertilizers are substances that contain microorganisms, which when added to the soil increase its fertility and promote plant growth.
2. It comprises living organisms which include mycorrhizal fungi, blue-green algae, and bacteria.
3. Mycorrhizal fungi preferentially withdraw minerals from organic matter for the plants.
4. Whereas cyanobacteria are characterized by the property of nitrogen fixation.
5. The bacteria fix nitrogen in both ways in symbiotic association with the plant as well as in a free-living state.

Explanation of the incorrect option:

Option A:

Nitrogen-fixing bacteria used as biofertilizers to fix atmospheric nitrogen.

Option B:

Nitrogen-fixing cyanobacteria -used as biofertilizer to fix nitrogen in free-living conditions.

Final answer: Biofertilizers include bacteria, cyanobacteria, and mycorrhizal fungi.