Which plant hormone is first produced in response to mechanical injury?

Explanation

The correct answer is (D) Systemin Explanation: • Systemin is a polypeptide plant hormone involved in the wound response in Solanaceous plants. • It acts as a primary signal that triggers the synthesis of defense proteins (like protease inhibitors) when the plant is mechanically injured or attacked by herbivores. Information Booster: • It was the first peptide hormone to be discovered in plants. Additional Knowledge: • Ethylene (Option A): Known as the ripening hormone; also released during stress but systemin is a specific injury signal. • Abscisic acid (Option C): Primarily involved in seed dormancy and stomatal closure during water stress. Copyright © 2026 Adda247