Morfamquat is a selective herbicide in that dicots but
not monocots are affected at the normal field rates (19).
The mechanism of this difference is not clearly understood
but probably relates to the ability of morfamquat to be
enzymatically converted to paraquat by esterases that
cleave the bulky side groups on the molecule. Once in the
cell, morfamquat then behaves identically to paraquat.
