Is the quiescent centre only found in monocot roots?
Note that quiescent centers are typically defined by cell division activity not anatomical placement and are not confined to monocots.

For example, this paper discusses the quiescent center in Arabidopsis roots1.



Reference:
1: Doerner, P. (1998). Root development: quiescent center not so mute after all. Current Biology, 8(2), R42-R44.