Paradormancy

Paradormancy is a form of dormancy in which growth is inhibited by signals originating from other organs within the same plant. The classic example is apical dominance, where the shoot apex suppresses the outgrowth of lateral buds. The inhibitory signal is usually a hormone produced near the apex and transported through the stem, keeping side shoots dormant while the apex remains.

Paradormancy differs from endodormancy, in which buds fail to grow due to internal physiological constraints within the meristem despite favorable external conditions, and ecodormancy, where the external environment prevents growth even though the buds are capable of growing.

Release from paradormancy occurs when the source of the inhibitory signal is removed, such as by pruning, debudding, or decapitating the shoot apex. With the apex removed, the downward transport of inhibitory signals diminishes, allowing lateral buds to break dormancy and resume growth. Environmental conditions may then influence the rate of growth.

In horticulture and forestry, understanding paradormancy informs practices for training, pruning, and shaping plants. Distinguishing paradormancy from endodormancy or ecodormancy helps managers decide whether to adjust pruning regimes, provide additional cues from light or temperature, or address internal dormancy issues to achieve desired plant architecture and yield.