Chlorsulfuron

Chlorsulfuron is a herbicide that belongs to the sulfonylurea group of chemicals. It is used primarily for the control of broadleaf weeds in cereal crops such as wheat, barley, and oats. Chlorsulfuron works by inhibiting the enzyme acetolactate synthase (ALS), which is essential for the growth and development of plants.

History

Chlorsulfuron was first registered for use in the United States in 1982. It was one of the first sulfonylurea herbicides to be developed and has since been used extensively in agriculture worldwide.

Mode of Action

Chlorsulfuron inhibits the enzyme acetolacture synthase (ALS), which is necessary for the synthesis of the amino acids leucine, isoleucine, and valine. This inhibition prevents the plant from growing and eventually leads to its death.

Use in Agriculture

Chlorsulfuron is used in a variety of cereal crops, including wheat, barley, and oats. It is applied pre-emergence or early post-emergence to control a wide range of broadleaf weeds, including wild mustard, pigweed, and lamb's quarters.

Environmental Impact

Chlorsulfuron is considered to be moderately toxic to birds and mammals, but is highly toxic to aquatic organisms. It is also known to have a long residual life in the soil, which can affect subsequent crops.

Health Effects

Exposure to chlorsulfuron can cause irritation to the eyes, skin, and respiratory tract. Long-term exposure can lead to more serious health effects, including damage to the liver and kidneys.

Regulatory Status

In the United States, chlorsulfuron is classified as a Restricted Use Pesticide (RUP) by the Environmental Protection Agency (EPA), meaning it can only be used by certified applicators.

Chemical structure of chlorsulfuron

See Also

• Sulfonylurea
• Herbicide
• Acetolactate synthase