Anthocyanin pigment synthesis in leaves is encouraged by deficiency of :

Options

A. `N_(2)`
B. C
C. Mg
D. Cl

Answer

**Step-by-Step Solution:**

1. **Understanding Anthocyanins**: Begin by recognizing that anthocyanins are a type of polyphenolic pigment found in plants. They are responsible for the red, purple, and blue colors in many fruits and flowers.

2. **Role of Anthocyanins**: Acknowledge that anthocyanins play several important roles in plants, including attracting pollinators, aiding in reproduction, and providing protection against biotic (living organisms) and abiotic (non-living environmental factors) stresses.

3. **Identifying Nutrient Deficiencies**: The question asks which nutrient deficiency encourages the synthesis of anthocyanin pigments in leaves. The options provided are nitrogen, C4 carbon, magnesium, and chlorine.

4. **Analyzing Each Option**:
- **Nitrogen**: Essential for overall plant growth and development; its deficiency can lead to stress conditions that may trigger anthocyanin production.
- **C4 Carbon**: This is not a nutrient but rather refers to a type of photosynthetic pathway; it does not directly relate to anthocyanin synthesis.
- **Magnesium**: Important for chlorophyll production; its deficiency can lead to yellowing of leaves but is not directly linked to increased anthocyanin synthesis.
- **Chlorine**: A micronutrient that plays a role in photosynthesis but does not have a known direct relationship with anthocyanin production.

5. **Conclusion**: Based on the analysis, the deficiency of nitrogen is the most likely cause for increased anthocyanin synthesis in leaves. Therefore, the correct answer is nitrogen.

**Final Answer**: Anthocyanin pigment synthesis in leaves is encouraged by deficiency of nitrogen.

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