A hormone which can substitute effect of cold treatment and photoperiodism to bring early flowering is

Options

A. ethylene
B. gibberellin
C. cytokinin
D. florigen

Answer

**Step-by-Step Text Solution:**

1. **Understanding the Question**: The question asks for a hormone that can mimic the effects of cold treatment and photoperiodism to promote early flowering in plants.

2. **Identifying the Hormones**: The options provided are ethylene, gibberellin, cytokinin, and fluorogen. We need to analyze each of these hormones to determine which one can substitute for cold treatment and photoperiodism.

3. **Analyzing Gibberellin**: Gibberellins are known plant hormones that play a significant role in various growth processes. They are particularly noted for their ability to promote flowering in certain plants that require cold treatment (vernalization) or specific light conditions (photoperiod).

4. **Effect of Gibberellin**: When gibberellin is applied to plants that typically require cold treatment, it can induce flowering without the need for low-temperature exposure. This makes gibberellin a suitable candidate for substituting the effects of cold treatment and photoperiodism.

5. **Conclusion**: Based on the analysis, the hormone that can substitute the effects of cold treatment and photoperiodism to bring about early flowering is **gibberellin**.

6. **Final Answer**: The correct option is **gibberellin**.

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