Early fruit drop can be avoided by spraying

Options

A. Auxin
B. Ethylene gas
C. Gibberellins
D. Cytokinin

Answer

**Step-by-Step Solution:**

1. **Understanding Early Fruit Drop**: Early fruit drop refers to the premature shedding of fruits from a plant before they have matured. This can be a significant issue for farmers and gardeners as it can lead to reduced yields.

2. **Role of Plant Hormones**: Plant hormones are crucial in regulating various physiological processes in plants, including growth, development, and responses to environmental stimuli. Different hormones have different effects on plant processes.

3. **Identifying Relevant Hormones**: The question provides several options: auxin, ethylene gas, gibberellins, and cytokinins. We need to determine which of these hormones can prevent early fruit drop.

4. **Analyzing Auxin**: Auxin is a plant hormone known for promoting growth and development. It plays a significant role in:
- Apical dominance (growth of the main stem over lateral buds).
- Inducing parthenocarpy (development of fruit without fertilization).
- Preventing early fruit and leaf drop by inhibiting abscission (the process of shedding).

5. **Analyzing Ethylene Gas**: Ethylene is a gaseous hormone primarily involved in the ripening of fruits. While it influences fruit maturation, it does not prevent early fruit drop.

6. **Analyzing Gibberellins**: Gibberellins are hormones that promote stem elongation, seed germination, and flowering. They do not have a direct role in preventing early fruit drop.

7. **Analyzing Cytokinins**: Cytokinins are involved in cell division and growth but do not specifically prevent early fruit drop.

8. **Conclusion**: Based on the analysis, auxin is the hormone that can effectively prevent early fruit drop by inhibiting the abscission process. Therefore, the correct answer is auxin.

**Final Answer**: Early fruit drop can be avoided by spraying **auxin**.

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