The term botanical tunic indicates a thin membrane, or layer of fibers, of papyrus texture, sometimes of brownish-reddish color, but most often whitish or colorless, having a protective and insulating function, covering some plant organs.
It is an external primary tegumental tissue, derived from the primary stem meristema, which is the aerial part of the primary body of the plant, and is usually monochromatic. In addition, the tunic is characterized by the absence of chloroplasts and the presence of attachments such as stomachs and hairs. In addition to having a general protective and general insulation, the tunic prevents water leaks, protects from abiotic factors such as UV rays and biotic factors such as bacterial pathogens and fungal infections. Tunics are very evident in bulbs, bulbs or tubers, some plant species, especially Allium and Romulea. In the common kitchen garlic, it is the thin membrane that covers the clot, which eliminates the use of the bulb (commonly known as the head) as a varied aroma.
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