Ground meristem The central region of the apical meristem from which the ground tissues of pith, cortex, medullary rays, and mesophyll differentiate. In root meristem it is also called periblem.

位于顶端分生组织的中部，髓、皮层、髓射线以及叶肉这些基本组织均是由基本分生组织分化而成。根部分生组织也称为皮层原。