A farmer adds Azotobacter culture to soil before sowing maize. Which mineral element will be replenished by doing so?

Options

A. N
B. P
C. K
D. S

Explanation

**Step-by-Step Solution:**

1. **Understanding Azotobacter**: Azotobacter is a type of bacteria that is known for its ability to fix atmospheric nitrogen. This means it can convert nitrogen gas (N₂) from the atmosphere into a form that plants can use.

2. **Role of Nitrogen in Plants**: Nitrogen is an essential mineral element for plants. It is a key component of amino acids, proteins, and nucleic acids, which are vital for plant growth and development.

3. **Process of Nitrogen Fixation**: The process involves Azotobacter taking in atmospheric nitrogen and converting it into ammonia (NH₃). This ammonia can then be further transformed into other nitrogenous compounds that plants can absorb.

4. **Impact on Soil Fertility**: By adding Azotobacter culture to the soil, the farmer is enhancing the nitrogen content in the soil. This replenishment of nitrogen increases the fertility of the soil, making it more conducive for growing crops like maize.

5. **Conclusion**: Therefore, the mineral element that will be replenished by adding Azotobacter culture to the soil is nitrogen.

**Final Answer**: The mineral element replenished by adding Azotobacter culture to soil is nitrogen.

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