DCMU

DCMU, commonly known as diuron, is a substituted urea herbicide used to control a wide range of annual grasses and broadleaf weeds. It is valued for its effectiveness in crop and noncrop settings and is typically applied as a pre-emergence or post-emergence treatment in many agricultural systems and turf management.

Chemical identity and naming: DCMU stands for 3-(3,4-dichlorophenyl)-1,1-dimethylurea. It is also referred to as diuron. Its molecular formula is C9H10Cl2N2O, and its chemical structure comprises a dichlorophenyl group attached to a dimethylurea moiety.

Mechanism of action: DCMU is a photosynthesis inhibitor that acts on photosystem II. It binds to the QB-binding site of the D1 protein in the thylakoid membrane, blocking electron flow from QA to QB. This disruption halts the photosynthetic electron transport chain, leading to plant death under exposure.

Applications and use patterns: Diuron is employed on a variety of crops including sugarcane, maize, citrus, grapes, vegetables, and in turf and ornamental plants. It can be used alone or in combination with other herbicides as part of integrated weed management programs. Its performance is influenced by factors such as soil type, moisture, and light exposure.

Environmental and safety considerations: DCMU is moderately persistent in soil and can reach surface water through runoff or leaching, with potential toxicity to aquatic organisms. It may contaminate groundwater under certain conditions. Regulations and usage guidelines vary by country; many regions impose restrictions due to environmental concerns. Proper handling, label-compliant application, and protective measures are advised.

See also: Photosystem II inhibitors; herbicides in the diuron/PSII inhibitor class.