Which structure may persist as a tuft of hairs on the fruit of Asteraceae plants?

The pappus is the structure that may persist as a tuft of hairs on the fruit of Asteraceae plants, commonly known as the daisy or sunflower family. This tuft of hairs, which can be feathery or bristle-like, serves important functions for the plant. Primarily, it aids in the dispersal of the seeds by utilizing wind currents. The lightweight nature of the pappus allows the seeds to be carried over distances, increasing the chances of germination in favorable conditions.

In Asteraceae, the pappus develops from the calyx and is often modified into various forms, contributing to the identification of different species within this diverse family. Its persistence on the fruit not only assists in seed dispersal but can also be a distinguishing characteristic when identifying Asteraceae plants in the field.

In contrast, the calyx typically does not remain attached to the fruit; it generally falls away after flowering. The sequence of leaves refers to the arrangement of leaves along the stem, which does not persist on the fruit itself. The ovary wall becomes the fruit pericarp and is not fluffy or hair-like but rather a structural component surrounding the seed.