what is vernalisation?

Vernalization is the process of inducing flowering in certain plants by exposing them to low temperature. Biennials and Perennials plants undergo this process of inducing flowering. The exposure to low temperature in certain plants have shown significant increase in seedling growth. For example in plants like wheat, millet, rice, cotton this is very common. So they show early flowering as compare to other seedlings that are not exposed to low temperature. So in other words,  it is pre-treatment of seeds to low temperature to induce early flowering in them.