The bacterium_____belonging to group Actinomycetes, produces `N_(2)-`fixing nodules on the roots of non-leguminous plants (e.g., Alnus)

Options

A. (a) Frankia
B. (b) Rhizobium
C. (c) Rhodospirillum
D. (d) Clostridium

Answer

**Step-by-Step Solution:**

1. **Identify the Group of Bacteria**: The question asks for a bacterium that belongs to the group Actinomycetes. Actinomycetes are a group of gram-positive bacteria known for their filamentous structure and ability to form spores.

2. **Analyze the Options**: The options provided are:
- A) Francia
- B) Rhizobium
- C) Rhodospirillum
- D) Clostridium

3. **Determine the Correct Bacterium**: Among the options, we need to identify which one is known for forming nitrogen-fixing nodules on the roots of non-leguminous plants.
- **Francia**: This bacterium is indeed part of the Actinomycetes group and is known for forming symbiotic relationships with non-leguminous plants like Alnus, producing nitrogen-fixing nodules.
- **Rhizobium**: This bacterium is primarily associated with leguminous plants, not non-leguminous.
- **Rhodospirillum**: This is a type of purple non-sulfur bacteria and does not form nodules.
- **Clostridium**: This is an anaerobic bacterium that does not form nodules on plant roots.

4. **Conclusion**: Based on the analysis, the correct answer is **Francia**, as it forms nitrogen-fixing nodules on the roots of non-leguminous plants such as Alnus.

5. **Final Statement**: Hence, the correct answer is option A, Francia.

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