The ploughing of field is the first step in the process of crop plantation. Which of the following statements about the usefulness of ploughing is incorrect?

Options

A. It promotes the growth of useful microbes in soil
B. It brings nutrients to the top layer of soil
C. It reduces the population of pests in soil
D. It helps in aerating the soil

Answer

To determine which statement about the usefulness of ploughing is incorrect, we need to analyze the given statements regarding ploughing and its effects on the soil and crop growth.

### Step-by-Step Solution:

1. **Understanding Ploughing**: Ploughing is the process of turning over the upper layer of soil, which helps in preparing the field for planting crops.

2. **Identifying the Benefits of Ploughing**:
- **Breaks Down Soil**: Ploughing breaks down the soil, making it loose and aerated, which is beneficial for root growth.
- **Promotes Microbial Growth**: By mixing the soil, ploughing promotes the growth of beneficial microbes, which are essential for nutrient cycling.
- **Brings Nutrients to the Surface**: Ploughing helps in bringing nutrients from the lower layers of soil to the top layer, making them more accessible to plants.
- **Reduces Pest Population**: This is where we need to be careful. While ploughing can disrupt the habitat of some pests, it does not necessarily reduce their population effectively.

3. **Evaluating the Statements**:
- **Statement 1**: Ploughing promotes the growth of useful microbes in the soil. (Correct)
- **Statement 2**: Ploughing brings nutrients to the top layer of the soil. (Correct)
- **Statement 3**: Ploughing reduces the population of pests in the soil. (Incorrect)
- **Statement 4**: Ploughing helps in breaking down the soil. (Correct)

4. **Conclusion**: The incorrect statement about the usefulness of ploughing is that it reduces the population of pests in the soil.

### Final Answer:
The incorrect statement about the usefulness of ploughing is: "It reduces the population of pests in the soil."

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