tuberrhizome

Tuberrhizome is an underground storage organ found in some plants that combines features of tubers and rhizomes. In botanical terms, a rhizome is a horizontal subterranean stem that produces roots from its underside and shoots from its nodes, while a tuber is a swollen tip of a stolon or root that stores nutrients. A tuberrhizome develops when a rhizomatous stem thickens and forms a tuber-like storage mass at one or more points, or along its length, while maintaining the ability to produce adventitious roots and aerial shoots from nodes. This combination allows both storage and clonal spread.

Morphologically, a tuberrhizome retains the rhizome's architecture of nodes and internodes, with storage tissue accumulating starches and other reserves. The thickened regions may be irregular and can vary in size along the rhizome. The structure is functional as a reserve source during unfavorable conditions and can support rapid regrowth and propagation when growth resumes.

Taxonomic usage varies. Some authors treat tuberrhizomes as a distinct organ type, others regard them as a form of rhizome that has acquired tuber-like storage capacity. In horticulture and ecology, they are noted in geophyte groups and in crops where clonal propagation via storage organs is advantageous.

Related terms include tuber and rhizome; tuberrhizome represents a conceptual middle ground between these storage organs.