Mention the most significant function/role of Azotobacter.

Explanation

**Step-by-Step Solution:**

1. **Identify Azotobacter**: Azotobacter is an aerobic bacterium, which means it requires oxygen for its growth and survival.

2. **Characterize its Habitat**: It is a free-living soil microbe, meaning it does not form symbiotic relationships with plants or other organisms. Instead, it exists independently in the soil.

3. **Understand its Role in the Nitrogen Cycle**: Azotobacter plays a crucial role in the nitrogen cycle, which is essential for maintaining soil fertility and supporting plant growth.

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