Folioläpistymisestä

Folioläpistymisestä, often translated as leaf adhesion or leaf abscission, is a biological process in plants where leaves detach from the stem. This is a crucial part of a plant's life cycle, allowing it to shed older, damaged, or senescent leaves. The process is controlled by hormonal changes within the plant, primarily involving auxins and ethylene. As leaves age, auxin production decreases, while ethylene production increases, signaling the formation of a specialized layer of cells at the base of the leaf stalk called the abscission layer.

The abscission layer consists of two parts: the separation layer and the protective layer. The separation layer is composed of thin-walled cells that weaken over time, eventually breaking down. Simultaneously, the protective layer forms a corky or waxy coating on the outer surface of the stem, preventing pathogens from entering the plant through the wound left by the detached leaf. Environmental factors such as changes in temperature, light duration, and water availability can also influence the timing and rate of folioläpistymisestä. In deciduous trees and plants, this process is a prominent feature of autumn, leading to the colorful display of changing leaves before they fall. In other plants, it can occur more gradually or in response to stress.