exact: portion of shoot-borne root primordium tissue
exact: primordio del eje del epiblasto de la raíz (Spanish)
broad: adventitious root primordium
Definition
A root primordium (PO:0005029) that is committed to the development of a shoot-borne root (PO:0000042). [source: POC:curators]
Comment
Transition from shoot-borne root primordium to shoot-borne root occurs with the formation of a root cap (PO:0020123), shortly after the development of a root apical meristem (PO:0020147).