What Is Abscisic Acid?
Abscisic acid is a plant hormone that is responsible for dormancy and the inhibition of growth, among other processes in plant development. When it was first discovered and tested, abscisic acid was thought to play a role in abscission, or the shedding of the plant’s leaves or fruit. This is part of how the hormone got its name, although most scientists no longer believe that abscisic acid has that function. This hormone may also be produced at certain times by a plant under stress, which may occur in situations such as a lack of water. The first time that abscisic acid was identified and described was in 1963. The scientist Frederick Addicott, in the company of his associates, was looking for the hormone that caused the abscission of fruit in cotton plants. Two different compounds were isolated, and at the time they were called abscisin I and abscisin II. The latter eventually came to be known as abscisic acid, even though its role in abscission is now considered dubious at best. Two
