Diquat

Diquat is a contact herbicide that rapidly desiccates the leaves of plants upon exposure. It is used in agriculture and horticulture to control a wide range of weed species. Diquat is also used in aquatic environments to control nuisance aquatic vegetation.

Chemistry

Diquat is a bipyridyl herbicide. The chemical formula of diquat is C12H12Br2N2. It is a yellow to brown liquid with a sharp odor. Diquat is highly soluble in water and is not volatile. It is stable under normal storage conditions.

Mode of Action

Diquat acts by interfering with photosynthesis, the process by which plants convert sunlight into chemical energy. It is a non-selective herbicide, meaning it will kill most plants it comes into contact with. Diquat is rapidly absorbed by plant tissues and is translocated within the plant but not to a great extent.

Health Effects

Exposure to diquat can cause irritation to the skin and eyes. Ingestion can cause nausea, vomiting, and diarrhea. Long-term exposure can lead to more serious health effects such as damage to the liver and kidneys.

Environmental Impact

Diquat is highly toxic to aquatic organisms. It can also be harmful to non-target plants if it drifts from the area where it is applied. However, diquat binds tightly to soil particles and is not likely to leach into groundwater.

Regulation

In the United States, diquat is classified as a Restricted Use Pesticide (RUP) by the Environmental Protection Agency (EPA). This means that it can only be purchased and used by certified applicators.

See Also

• Paraquat
• Herbicide
• Pesticide