The nitrogen fixation of atmospheric nitrogen in the soil is a result of the activity performed by certain beneficial micro-organisms, which live in association with plants. The symbiotic nitrogen fixing bacteria found in the root nodules of legumes is known as

Options

A. Azotobacter
B. Rhizobium
C. Anabaena
D. Oscillatoria

Answer

**Step-by-Step Solution:**

1. **Understanding Nitrogen Fixation**: Nitrogen fixation is the process by which atmospheric nitrogen (N₂) is converted into a form that plants can use, such as ammonia (NH₃). This process is essential for plant growth as nitrogen is a crucial nutrient.

2. **Role of Microorganisms**: Certain beneficial microorganisms, particularly bacteria, play a significant role in nitrogen fixation. These bacteria can convert atmospheric nitrogen into a usable form for plants.

3. **Symbiotic Relationship**: Some of these nitrogen-fixing bacteria form a symbiotic relationship with specific plants, particularly legumes. In this relationship, both the bacteria and the plants benefit from each other.

4. **Location of Nitrogen-Fixing Bacteria**: The symbiotic nitrogen-fixing bacteria are found in the root nodules of leguminous plants. These root nodules provide a suitable environment for the bacteria to thrive.

5. **Identifying the Bacteria**: The specific bacteria that are known for their symbiotic relationship with legumes and are responsible for nitrogen fixation are called **Rhizobium**.

6. **Conclusion**: Therefore, the symbiotic nitrogen-fixing bacteria found in the root nodules of legumes is known as **Rhizobium**.

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