It is known that some varieties of wheat are sown in autumn but are harvested around next mid-summer.
$(A)$ What could be the probable reason for this?
$(B)$ What term is used for this promotion of flowering under low temperature?
$(C)$ Which plant hormone can replace the cold treatment?

(B) Annual winter wheat plants require a full growing season to complete their vegetative growth before initiating flowers and fruits. By sowing in autumn,they are exposed to low temperatures throughout the winter,which is essential for them to reach vegetative maturity. They resume growth in spring and produce flowers and grains by mid-summer.
$(B)$ The process of using chilling or cold treatment to promote or accelerate flowering is called vernalisation. It shortens the juvenile or vegetative phase,thereby hastening the transition to the reproductive phase. This stimulus is perceived specifically by meristematic cells,such as the shoot tip,embryo tip,root apex,and developing leaves.
$(C)$ Gibberellic acid $(GA)$ treatment can replace the cold treatment and induce early flowering by reducing the vegetative growth period in many long-day plants.