Radicle

The radicle is an embryonic organ in vascular plants that develops into its root system. The radicle drastically changes during development, and its appearance in maturation differs depending on the embryo’s clade. In all angiosperms, the radicle develops into a primary root. However, in typical monocots, this radicle remains the primary root, and lateral roots develop off of it, before later dying off; in typical eudicots, the radicle thickens into a taproot and forms the center of the taproot system. This may differ in plants where the root organs must be modified, such as where the taproot thickens into a storage root.

In maturing eudicots, a hook forms within the growing taproot. The location of this hook may vary, but it will always remain within the developed radicle. This hook does not tend to form in monocots.