Most famous bacterial biofertilizer is

Options

A. Nitrosomonas
B. Nitrobacter
C. Nitrosococcus
D. Rhizobium

Answer

**Step-by-Step Solution:**

1. **Understanding Biofertilizers**: Biofertilizers are substances that contain living microorganisms, which help to enhance the nutrient quality of the soil. They are used to improve soil fertility and promote plant growth.

2. **Identifying Types of Biofertilizers**: Common types of biofertilizers include nitrogen-fixing bacteria, cyanobacteria (blue-green algae), and certain fungi. These microorganisms play a crucial role in enriching the soil with essential nutrients.

3. **Analyzing the Given Options**: The options provided are:
- A) Nitrosomonas
- B) Nitrobacter
- C) Nitrosococcus
- D) Rhizobium

4. **Understanding Nitrifying Bacteria**: The first three options (Nitrosomonas, Nitrobacter, and Nitrosococcus) are known as nitrifying bacteria. They participate in the nitrification process, which involves the conversion of ammonia into nitrite and then into nitrate, making nitrogen available to plants.

5. **Identifying the Most Famous Biofertilizer**: Among the options, Rhizobium is a well-known nitrogen-fixing bacterium that forms symbiotic relationships with leguminous plants (like beans). It helps in the fixation of atmospheric nitrogen into a form that plants can utilize, making it a crucial biofertilizer.

6. **Conclusion**: Based on the information analyzed, the most famous bacterial biofertilizer is Rhizobium, which is widely recognized for its role in enhancing soil fertility through nitrogen fixation.

**Final Answer**: The most famous bacterial biofertilizer is **Rhizobium** (Option D).

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