Which growth regulator promotes root initiation, flowering and induced parthenocarpy

Options

A. Gibberellin
B. Auxin
C. Cytokinin
D. Ethylene.

Answer

To solve the question "Which growth regulator promotes root initiation, flowering, and induced parthenocarpy?", we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Question**: We need to identify a growth regulator that has three specific functions: promoting root initiation, aiding in flowering, and inducing parthenocarpy.

2. **Review the Options**: The options provided include:
- A) Juberline
- B) Auxin
- C) Cytokinin
- D) Ethylene

3. **Analyze Each Option**:
- **Juberline**: This growth regulator is primarily known for its role in seed germination. It does not significantly promote root initiation or flowering. Thus, it is not the correct answer.

- **Auxin**: Auxin, particularly indole acetic acid, is known to promote root initiation and is also involved in the process of flowering. Additionally, auxin can induce parthenocarpy, which is the development of fruit without fertilization (e.g., seedless bananas). This makes auxin a strong candidate for the correct answer.

- **Cytokinin**: This hormone is primarily involved in promoting cell division and delaying senescence (aging) in plants. It does not directly promote root initiation or flowering, making it an incorrect choice.

- **Ethylene**: Ethylene is a gaseous hormone that primarily regulates fruit ripening. It does not promote root initiation or flowering, so it is also not the correct answer.

4. **Conclusion**: Based on the analysis, the growth regulator that promotes root initiation, flowering, and induced parthenocarpy is **Auxin**.

### Final Answer:
The correct growth regulator is **Auxin**.

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