Guttation happens due to the development of

Options

A. Negative hydrostatic pressure in xylem
B. Positive hydrostatic pressure in xylem
C. Intense transpiration pull
D. Low root pressure

Answer

**Step-by-Step Text Solution:**

1. **Understanding Guttation**: Guttation is the process of loss or excretion of water in the form of liquid droplets from the plant. This phenomenon is commonly observed in the early morning.

2. **Hydathodes**: Guttation occurs through small pores on the margins and tips of the leaves, known as hydathodes. These structures are specialized for the excretion of water.

3. **Structure of Hydathodes**: Hydathodes are made up of loosely arranged, colorless parenchymatous cells called epitheme. These cells are located over the tip of the vascular strand and have a permanent opening called a water pore or water stoma.

4. **Mechanism of Guttation**: The process of guttation is driven by positive hydrostatic pressure in the xylem, which is generated by the root pressure. This pressure pushes water upwards through the plant and out through the hydathodes.

5. **Root Pressure**: Root pressure is the pressure exerted by the roots of the plant, which can lead to the exudation of water. It is important to note that this is different from negative hydrostatic pressure, which occurs in tall plants due to transpiration.

6. **Conclusion**: Guttation primarily occurs in herbaceous plants due to the positive root pressure, making it a unique feature of these types of plants. Therefore, the development of root pressure is the key factor that leads to guttation.

**Final Answer**: Guttation happens due to the development of root pressure.

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