Root pressure develops during

Options

A. Night time
B. Early mornings
C. Mid afternoons
D. 1 and 2

Answer

**Step-by-Step Solution:**

1. **Understanding Root Pressure**: Root pressure is a positive pressure that develops in the roots of plants. It is created when roots absorb water and minerals from the soil.

2. **Mechanism of Root Pressure**: When roots or root hairs absorb water and minerals, this leads to an increase in pressure within the roots. This pressure helps in the upward movement of water and minerals through the xylem to the stems and leaves.

3. **Conditions for Root Pressure Development**: For root pressure to develop effectively, two main conditions must be met:
- Low evaporation rates.
- Presence of moisture in the environment.

4. **Evaluating Time Periods**:
- **Night Time**: At night, there is no sunlight, which means lower temperatures and reduced evaporation. This condition is favorable for root pressure to develop.
- **Early Mornings**: During early mornings, the environment often has high humidity and moisture, and the evaporation rate is still low. This also supports root pressure development.
- **Mid Afternoons**: In contrast, during mid-afternoons, the sun is at its peak, leading to high evaporation rates. This would hinder the development of root pressure as the plant would rely more on transpirational pull.

5. **Conclusion**: Based on the analysis, root pressure develops during the night and early morning. Therefore, the correct answer is both options one (night time) and two (early mornings).

6. **Final Answer**: The correct option is **D (one and two)**.

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