Symbiotic nitrogen fixation is carried out in the nodules of leguminous plants by ……………………………….

Explanation

### Step-by-Step Solution:

1. **Understanding Symbiotic Nitrogen Fixation**:
- Symbiotic nitrogen fixation refers to the process where certain bacteria live in association with the roots of leguminous plants and convert atmospheric nitrogen into a form that the plants can use.

2. **Identifying the Bacteria Involved**:
- The primary bacteria responsible for this process in leguminous plants are known as Rhizobium. These bacteria form nodules on the roots of the plants.

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