Which of these is not a function of the gaseous hormone ?

Options

A. Initiation of flowering and synchronization of fruit - set in pineapples
B. Promotion of male flowers in cucumbers thereby increasing its yield
C. Breaking the bud dormancy and promoting sprouting of potato tubers
D. Promotion of root growth and root hair formation, thus helping the the plants to increase their absorption surface.

Answer

To solve the question "Which of these is not a function of the gaseous hormone?", we will analyze the functions of ethylene, the primary gaseous hormone in plants, and evaluate the provided options.

### Step-by-Step Solution:

1. **Identify the Gaseous Hormone**:
- The main gaseous hormone in plants is ethylene. It plays various roles in plant growth and development.

2. **Understand the Functions of Ethylene**:
- Ethylene is known for its role in:
- **Senescence**: It regulates the aging process in plants.
- **Ripening of Fruits**: It is crucial for the ripening process of many fruits.
- **Flowering**: It can initiate flowering in certain plants, such as pineapples and mangoes.
- **Breaking Dormancy**: It helps in breaking seed and bud dormancy, promoting germination.
- **Root Development**: It promotes root growth and root hair formation, enhancing nutrient absorption.

3. **Evaluate Each Option**:
- **Option 1**: Initiation of flowering and synchronization of fruit set in pineapples.
- This is a correct function of ethylene.
- **Option 2**: Promotion of male flowers in cucumbers and thereby increasing its yield.
- This is incorrect. Ethylene promotes female flowers in cucumbers, which increases yield.
- **Option 3**: Breaking the bud dormancy and promoting sprouting of potato tubers.
- This is a correct function of ethylene.
- **Option 4**: Promotion of root growth, root hair formation, thus helping the plants to increase their absorption surface.
- This is also a correct function of ethylene.

4. **Conclusion**:
- The option that is **not** a function of the gaseous hormone (ethylene) is **Option 2**: Promotion of male flowers in cucumbers.

### Final Answer:
**Option 2**: Promotion of male flowers in cucumbers and thereby increasing its yield.

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