The element which plays an important role in stomatal movement and its deficiency causes mottled chlorosis is

Options

A. `Mg^(2+)`
B. N
C. P
D. `K^(+)`

Answer

**Step-by-Step Solution:**

1. **Identify the Element Related to Stomatal Movement:**
The question asks for an element that plays a crucial role in stomatal movement. The element that is known for this function is potassium (K).

2. **Understand the Role of Potassium:**
Potassium is an essential macronutrient in plants. It is primarily absorbed in the form of K⁺ ions and is vital for various physiological processes in plants, including the regulation of stomatal opening and closing.

3. **Recognize the Symptoms of Deficiency:**
The question mentions that the deficiency of this element causes mottled chlorosis. Mottled chlorosis is a condition where leaves exhibit yellowing with green patches, often associated with potassium deficiency.

4. **List Functions of Potassium:**
- It helps in maintaining the anion-cation balance within the plant.
- It is crucial for the opening and closing of stomata, which regulates gas exchange.
- It activates several enzymes that are important for various metabolic processes.
- It plays a role in photosynthesis and chlorophyll synthesis.
- It helps maintain cell turgidity, which is essential for plant structure and function.

5. **Conclude the Answer:**
Based on the above points, the element that plays an important role in stomatal movement and whose deficiency leads to mottled chlorosis is potassium (K⁺).

**Final Answer: Potassium (K)**

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