Mottle leaf in citrus plants is due to the deficiency of

Options

A. boron
B. zinc
C. magnesium
D. molybdenum

Answer

### Step-by-Step Solution:

1. **Understanding Mottle Leaf Disease**:
- Mottle leaf disease is characterized by the appearance of uneven spots on the leaves of citrus plants. These spots are typically whitish and yellowish in color.

2. **Identifying the Cause**:
- The whitish and yellowish spots on the leaves are primarily due to a deficiency in chlorophyll, which is essential for the green color of leaves and for photosynthesis.

3. **Linking Chlorophyll Deficiency to Mineral Deficiency**:
- The lack of chlorophyll in plants can be attributed to the deficiency of certain minerals. In this case, we need to identify which mineral deficiency leads to mottle leaf disease.

4. **Evaluating the Options**:
- The options given are boron, zinc, magnesium, and molybdenum.
- Among these, zinc is known to play a crucial role in chlorophyll synthesis and is often linked to chlorosis (yellowing of leaves).

5. **Conclusion**:
- Based on the information, the mottle leaf disease in citrus plants is primarily due to the deficiency of zinc. Therefore, the correct answer is zinc.

### Final Answer:
Mottle leaf in citrus plants is due to the deficiency of **zinc**.

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