Gibberellin takes part in

Options

A. Bolting of rosette plants
B. Replacing long day requirement
C. Overcoming genetic dwarfism
D. All the above.

Answer

**Step-by-Step Solution:**

1. **Understanding Gibberellin:**
- Gibberellin is a plant hormone that plays a crucial role in promoting growth, particularly in stem elongation.

2. **Analyzing the Options:**
- The question provides several options regarding the roles of gibberellin:
a. Bolting of rosette plants
b. Replacing long day requirement
c. Overcoming genetic dwarfism
d. All of the above

3. **Explaining Bolting of Rosette Plants:**
- Bolting refers to the rapid elongation of the stem in rosette plants, which typically occurs under long day conditions or cold treatment. Gibberellin can induce this process artificially, allowing the plant to bolt even without the required environmental conditions.

4. **Replacing Long Day Requirement:**
- Since gibberellin can induce bolting in rosette plants under normal conditions, it effectively replaces the need for long day exposure that is typically necessary for this process.

5. **Overcoming Genetic Dwarfism:**
- Gibberellin promotes the elongation of internodes, which helps dwarf plants grow taller and overcome genetic dwarfism. This means that even genetically short plants can achieve normal height with the application of gibberellin.

6. **Conclusion:**
- Since gibberellin is involved in all three processes mentioned in the options, the correct answer is that gibberellin takes part in "all of the above."

**Final Answer:**
Gibberellin takes part in bolting of rosette plants, replacing long day requirement, and overcoming genetic dwarfism. Therefore, the answer is **all of the above**.

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