Phytomer

Synonyms

Metamer

Definition

A phytomer, from Greek φυτον, “plant,” and μερίς, “part,” thus literally “plant part,” is a constructional unit, consisting of a node, a leaf at that node, a lateral bud in the axil of the leaf (sometimes not present), and a portion of stem called internode (Bell 2008). Opinions differ as to whether the internode proximal or distal to the node should be included in the definition (Bell 2008). Phytomers are the product of the activity of a shoot apical meristem, possibly embedded within a terminal bud. Sometimes the terminal or lateral buds grow out into flowers, thereby exhausting the activity of the meristem. The aerial parts of every higher plant constitute a collection of phytomers, with varying shapes and dimensions of its constituting organs, resulting from differential growth and development dynamics. In a Functional-structural Plant Modeling (FSPM), the identification of a phytomer within a branched structure is aided using two topological indices,...