Question

What is abscission zone? Name its components and their functions.

Answer 1

Abscission is a process that initiates the removal/shedding of a part of plant following the formation of a protective layer that protects the inner tissues from desiccation. Leaf abscission is a very common phenomenon. The protective layer, and the region of separation, i.e. abscission layer are collectively termed as abscission zone. This zone initiates the process of abscission. The protective layer provides protection and acts as a defensive measure against infections. The cells in this layer may become lignified. During the process of abscission, walls of the cells forming the abscission layer undergo dissolution due to which the petiole remains attached to the stem only by the vascular elements.Thereafter due to wind or the gravity pull, the leaf is separated from the parent plant. Abscission layer leads to the formation of protective layer across the area left by the abscission.