prostem
Prostem is a term occasionally found in historical or speculative discussions of plant development to describe an early, undifferentiated tissue proposed to give rise to the plant stem axis. The term is not widely used in contemporary botany and is generally considered to be obsolete or hypothetical rather than a standard description of developmental processes.
The word combines pro-, meaning before, with stem, signaling a position preceding the mature stem axis. In
In proposed models, prostem would be a pluripotent or multipotent tissue that precedes the primary shoot apical
Because of limited evidence and inconsistent application, the term prostem is rarely used in modern plant biology.
See also: meristem, shoot apical meristem, proembryo, protocorm, plant development.