abscission

botany

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July 23, 2026

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Abscission is the process by which plants shed parts like leaves, fruits, or flowers. This shedding occurs at a specialized region called the abscission zone, which is often marked by a constriction. Within this zone, a separation layer forms, composed of cells that facilitate the detachment of the plant part.123

Plant hormones play a crucial role in regulating abscission. Abscisic acid and ethylene are growth inhibitors that promote leaf fall. Conversely, auxins, a type of growth promoter, can inhibit abscission, particularly when they reach the abscission zone from the tip of the structure. The interaction of these hormones, along with the synthesis of enzymes at the abscission zone, orchestrates the shedding process.45

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hormone
Auxins
…and in leaf fall (abscission). In experimental conditions, auxins tend to inhibit the progress of plant aging, perhaps because of their stimulating effect upon protein synthesis.
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…and in leaf fall (abscission). In experimental conditions, auxins tend to inhibit the progress of plant aging, perhaps because of their stimulating effect upon protein synthesis.
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aging
Reproduction and aging
…processes—including ripening and falling (abscission) of fruits and drying of seed pods—that are inseparable from the overall senescence process. Moreover, the onset of plant senescence is invariably initiated by the changing levels of hormones, which are under systemic or environmental control. If, for example, the hormone auxin is prevented,…
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…processes—including ripening and falling (abscission) of fruits and drying of seed pods—that are inseparable from the overall senescence process. Moreover, the onset of plant senescence is invariably initiated by the changing levels of hormones, which are under systemic or environmental control. If, for example, the hormone auxin is prevented,…
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plant development
Seasonal adaptations
…water stress and in leaf abscission (the separation of the leaf from the plant); there is a great deal of debate among scientists concerning what role, if any, this hormone plays in abscission. Other signaling hormones, such as indole-3-acetic acid (an auxin) and ethylene, appear to play a more significant…
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…water stress and in leaf abscission (the separation of the leaf from the plant); there is a great deal of debate among scientists concerning what role, if any, this hormone plays in abscission. Other signaling hormones, such as indole-3-acetic acid (an auxin) and ethylene, appear to play a more significant…
Read More