Sympodial growth is a bifurcating branching pattern where one branch develops more strongly than the other, resulting in the stronger branches forming the primary shoot and the weaker branches appearing laterally. A sympodium, also referred to as a sympode or pseudaxis, is the primary shoot, comprising the stronger branches, formed during sympodial growth. The pattern is similar to dichotomous branching; it is characterized by branching along stems or hyphae. In

botany Botany, also called plant science (or plant sciences), plant biology or phytology, is the science of plant life and a branch of biology. A botanist, plant scientist or phytologist is a scientist who specialises in this field. The term "bot ...

, sympodial growth occurs when the apical meristem is terminated and growth is continued by one or more lateral meristems, which repeat the process. The apical meristem may be consumed to make an inflorescence or other

determinate In logic and philosophy (especially metaphysics), a property is a characteristic of an object; a red object is said to have the property of redness. The property may be considered a form of object in its own right, able to possess other propertie ...

structure, or it may be aborted.

Types

If the sympodium is always formed on the same side of the branch bifurcation, e.g. always on the right side, the branching structure is called a helicoid cyme or bostryx. If the sympodium occurs alternately, e.g. on the right and then the left, the branching pattern is called a scorpioid cyme or cincinus (also spelled cincinnus). Leader displacement may result: the stem appears to be continuous, but is in fact derived from the meristems of multiple lateral branches, rather than a monopodial plant whose stems derive from one meristem only.Simpson, M. G. 2006. ''Plant Systematics.'' Elsevier Academic Press. Pg. 355. Dichotomous substitution may result: two equal laterals continue the main growth.

In orchids

In some orchids, the apical meristem of the rhizome forms an ascendent swollen stem called a

pseudobulb The pseudobulb is a storage organ found in many epiphytic and terrestrial sympodial orchids. It is derived from a thickening of the part of a stem between leaf nodes and may be composed of just one internode or several, termed heteroblastic a ...

, and the apical meristem is consumed in a terminal inflorescence. Continued growth occurs in the rhizome, where a lateral meristem takes over to form another pseudobulb and repeat the process. This process is evident in the jointed appearance of the rhizome, where each segment is the product of an individual meristem, but the sympodial nature of a stem is not always clearly visible.

References

{{Reflist Plant morphology Orchid morphology