What is the main role of vernalisation in plants?

Explanation

### Step-by-Step Text Solution:

1. **Definition of Vernalization**: Vernalization is a physiological process in plants where exposure to a prolonged period of low temperatures induces flowering. This process is crucial for certain plants that require cold conditions to trigger their reproductive phase.

2. **Role in Flowering**: The primary role of vernalization is to promote flowering in plants. For many species, especially biennials, exposure to cold temperatures is necessary to transition from the vegetative stage to the flowering stage. This ensures that flowering occurs at the right time, typically in spring, when conditions are favorable for seed production.

3. **Conversion of Biennials to Annuals**: Vernalization allows biennial plants (which typically take two years to complete their life cycle) to complete their life cycle in one growing season. This adaptation is particularly beneficial in environments where the growing season is short.

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