Diquat is a contact herbicide that produces desiccation and defoliation. As an ionic compound, it may have a variety of counterions associated with it. The herbicide is most often used as the dibromide salt, diquat dibromide. Brand names for this formulation include Aquacide, Dextrone, Preeglone, Deiquat, Detrone, Reglone, Reglon, Reglox, Ortho-Diquat and Weedtrine-D.
Diquat is a non-selective herbicide that acts quickly to damage only that parts of the plant to which it is applied. It breaks down quickly upon exposure to soil, leaving little residue.
Diquat dibromide is moderately toxic. It may be fatal to humans if swallowed, inhaled, or absorbed through the skin in sufficient quantities.
Diquat is synthesized from 2,2'-bipyridine.