rhizomer

Rhizomer is a botanical term used to describe a repeating unit along a rhizome, a horizontal underground stem. Each rhizomer is analogous to a metamer along a shoot and typically includes a node bearing buds, an internodal segment, and often roots that emerge from the node. This modular organization supports the rhizome’s ability to grow horizontally, store resources, and regenerate after disturbance.

Rhizomeres occur in many rhizomatous plants, such as certain grasses, perennials, and ferns. The size, number, and arrangement of rhizomeres influence the plant’s overall architecture, branching patterns, and propagation capacity. In developmental studies, rhizomers provide a framework for describing positional information along the rhizome and for comparing modularity across species. Terminology can vary, and some authors use rhizomer and rhizomere interchangeably or with slight definitional differences.

In broader plant biology, the concept of rhizomer complements discussions of nodes, internodes, and metamerism, highlighting how modular units along underground stems contribute to growth form, resilience, and clonal spread. While not as widely standardized as shoot metamer terminology, the rhizomer concept remains useful for describing the structural and developmental organization of rhizomatous plants.