Pecíolo

Pecíolo is the botanical term for the stalk that attaches a leaf blade to the stem of a plant. It is essentially the leaf's stem. The petiole's primary function is to support the leaf blade and to position it in a way that maximizes light absorption for photosynthesis. It also serves as a conduit, containing vascular tissues (xylem and phloem) that transport water and nutrients from the stem to the leaf, and sugars produced during photosynthesis from the leaf to the rest of the plant.

The length and structure of petioles can vary greatly among different plant species. Some petioles are very short, almost appearing as though the leaf is directly attached to the stem, while others can be quite long and slender. In some cases, the petiole may be flattened or winged, contributing to the overall shape of the leaf. The point where the petiole attaches to the stem is called the node. Leaf scars are often visible on the stem where petioles were attached on previous seasons.

In certain plants, the petiole can undergo modifications. For example, in some species of *Acacia*, the petiole is flattened and broadened, taking on a leaf-like appearance and performing photosynthesis; these are called phyllodes. Conversely, some plants have leaves that lack a petiole entirely; these are referred to as sessile leaves. The presence or absence of a petiole, and its characteristics, are often important features used in plant identification.