Name the hormone involved in vernalisation.

Answer

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

1. **Understanding Vernalization**: Vernalization is a process that involves exposing seeds or plants to low temperatures, typically around 0 degrees Celsius. This exposure helps to induce flowering in certain plants that require a cold period to trigger their reproductive phase.

2. **Effect of Low Temperature**: When seeds are exposed to low temperatures, their metabolic activities slow down significantly, leading to a state of dormancy. This dormancy allows the seeds to remain intact without germinating until conditions are favorable.

3. **Role of Hormones**: While low temperatures are a natural method for vernalization, certain hormones can also mimic this effect. The primary hormone involved in this process is gibberellin. Gibberellins can promote flowering and can be used in place of vernalization.

4. **Application of Gibberellins**: When gibberellins are applied to plants that do not flower naturally, they can stimulate the flowering process, similar to the effects of vernalization. It is essential that seeds are moist before the application of gibberellins for effective results.

5. **Hypothetical Hormone**: Additionally, there is a hypothetical chemical known as "vernaline" which is suggested to be involved in the vernalization process. However, gibberellins are the main hormones recognized for their role in promoting flowering as a substitute for vernalization.

**Final Answer**: The hormone involved in vernalization is gibberellin.

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