Which one is used in biogas generation ?

Options

A. Rhizobium
B. Methanobacterium
C. Agrobacterium
D. Azotobacter

Answer

**Step-by-Step Solution:**

1. **Understanding Biogas**:
- Biogas is a mixture of gases, primarily methane (CH4), carbon dioxide (CO2), and hydrogen sulfide (H2S). It is produced through the anaerobic digestion of organic matter.

2. **Identifying the Options**:
- The options given are Rhizobium, Methanobacterium, Agrobacterium, and Azotobacter. We need to determine which of these is involved in biogas production.

3. **Analyzing Each Option**:
- **Rhizobium**: This bacterium is primarily known for its role in nitrogen fixation in legumes and does not contribute to biogas production.
- **Methanobacterium**: This is a type of methanogen, which is a group of archaea that produce methane as a metabolic byproduct in anaerobic conditions. They play a crucial role in biogas generation by decomposing organic matter.
- **Agrobacterium**: This bacterium is known for its role in plant genetic engineering and does not contribute to biogas production.
- **Azotobacter**: This is a free-living nitrogen-fixing bacterium that enhances soil fertility but is not involved in biogas production.

4. **Conclusion**:
- The bacterium that is specifically involved in biogas generation is **Methanobacterium**. It is responsible for the production of methane through the decomposition of organic matter in anaerobic conditions.

5. **Final Answer**:
- The correct answer is **Methanobacterium**.

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