Which one among the following chemical is used for causing defoliation & for causing defoliation of forest trees

Options

A. amo 1618
B. phosphonD
C. malic hydrazide
D. 2,4-D

Explanation

### Step-by-Step Solution:

1. **Understanding Defoliation**:
- Defoliation is the process of removing leaves from a plant. This can occur naturally or can be induced by certain chemicals.

2. **Identifying the Chemicals**:
- The question provides several chemical options, and we need to evaluate each one to determine which is used for defoliation.

3. **Evaluating Each Option**:
- **Option 1: MO1618**:
- This chemical is known to suppress stem elongation. Since it does not relate to leaf removal, it is not the correct answer.
- **Option 2: Phosphon D**:
- Phosphon D enhances the electron transport chain (ETC) during photosynthesis. It promotes growth rather than causing defoliation, so it is also not the correct answer.
- **Option 3: Malic Hydrosol**:
- This chemical induces dormancy in plants, inhibiting growth. Since it does not cause leaf removal, it is not the correct answer.
- **Option 4: 2,4-D (2,4-Dichlorophenoxyacetic acid)**:
- This is a synthetic auxin (plant hormone) that acts as a defoliant. It overstimulates plant growth, leading to premature leaf fall.

4. **Conclusion**:
- After evaluating all the options, the correct answer is **2,4-D**, as it is specifically used for defoliation of forest trees and other plants.

### Final Answer:
The chemical used for causing defoliation of forest trees is **2,4-D (2,4-Dichlorophenoxyacetic acid)**.

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