The most important function of Rhizobium is

Options

A. nitrogen assimilation
B. nitrogen fixation
C. ammonification
D. nitrification

Answer

**Step-by-Step Solution:**

1. **Understanding Rhizobium**: Rhizobium is a type of bacteria that forms a symbiotic relationship with the roots of leguminous plants (plants belonging to the family Leguminosae).

2. **Identifying Functions of Rhizobium**: The main functions of Rhizobium include:
- Nitrogen fixation
- Nitrogen assimilation
- Ammonification
- Nitrification

3. **Defining Nitrogen Fixation**: The most important function of Rhizobium is nitrogen fixation. This process involves converting atmospheric nitrogen (N₂) into a form that plants can absorb and utilize, such as ammonia (NH₃).

4. **Explaining Other Processes**:
- **Nitrogen Assimilation**: This is the process where inorganic nitrogen is converted into organic compounds, such as amino acids, which are necessary for plant growth.
- **Ammonification**: This refers to the breakdown of nitrogen-containing compounds (like proteins) into ammonia by microorganisms.
- **Nitrification**: This is a biological process where ammonia is converted into nitrates and nitrites, which are forms of nitrogen that plants can also use.

5. **Conclusion**: Among the options provided, the most significant function of Rhizobium is nitrogen fixation, as it directly contributes to the availability of nitrogen in a form that plants can utilize for their growth.

**Final Answer**: The most important function of Rhizobium is nitrogen fixation.

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