One of the commonly used plant growth hormone in tea plantations is

Options

A. Zeatin
B. ABA
C. IAA
D. Ethylene.

Answer

**Step-by-Step Solution:**

1. **Identify the Question**: The question asks for a commonly used plant growth hormone in tea plantations.

2. **Review the Options**: The options provided are zeatin, ABA (abscisic acid), IAA (indole acetic acid), and ethylene.

3. **Understand Each Hormone**:
- **Zeatin**: This is a type of cytokinin that promotes cell division (cytokinesis) but is not specifically used in tea plantations.
- **ABA (Abscisic Acid)**: Known as the stress hormone, it helps plants cope with stress but is not primarily used for growth promotion in tea.
- **IAA (Indole Acetic Acid)**: This is a form of auxin, which is crucial for promoting growth, particularly in stem elongation and apical dominance.
- **Ethylene**: This hormone is involved in the ripening of fruits and senescence of leaves, not in promoting growth in tea plantations.

4. **Determine the Correct Answer**: Among the options, IAA (indole acetic acid) is the most relevant hormone used in tea plantations because it promotes cell elongation and is essential in the process of vegetative propagation through stem cuttings.

5. **Conclusion**: The commonly used plant growth hormone in tea plantations is **IAA (Indole Acetic Acid)**.

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