Question

Azotobacter is used as:

• A. Pesticide
• B. Bio-fertilizer
• C. Fungicide
• D. Nematicide

Hint:

Remember the nitrogen-fixing categories:
- Symbiotic: Rhizobium (for legumes).
- Free-living (Asymbiotic): Azotobacter (for non-legumes).
- Associative: Azospirillum.

Answer 1

The Correct Option is B

Step 1: Understanding the Concept:
Bio-fertilizers are preparations containing living microorganisms that, when applied to seed, plant surfaces, or soil, colonize the rhizosphere and promote growth by increasing the availability of primary nutrients.

Step 2: Detailed Explanation:
Azotobacter is a genus of free-living, aerobic, heterotrophic, nitrogen-fixing bacteria.
It fixes atmospheric nitrogen non-symbiotically in the soil and makes it available to non-leguminous crops (such as wheat, maize, cotton, and vegetables).
Therefore, it is widely formulated and utilized as a highly effective bio-fertilizer.

Step 3: Final Answer:
The correct option is (B).