The role of cytokinins (CK) in mediating effects of light on stem elongation is unclear but they somehow appear to interact with other hormones
CK can apparently promote stem elongation in light-grown A. thaliana either through blocking ethylene action or IAA transport
Furthermore, the effects of CK may vary in light- and dark-grown plants.
In light-grown A. thaliana there was no effect of CK application on hypocotyl elongation but in the dark CK inhibited hypocotyl elongation
Taken together, the role of CK in photomorphogenesis is still unclear.