Thanks for bringing this up, almost forgot about it.
Cleavage furrow is formed from an actin-myosin contractile ring. It's predominantly actin, but myosin is in there.
Cell plate formation is derived from Golgi vesicles that contain cell membrane/cell wall stuff. Mainly, the cell plate is made up of callose (beta-1,3 polysaacharide) and then when cytokinesis is over, the cell plate turns into the new cell wall containing cellulose (beta-1,4 polysaacharide).