Quizalofop

Quizalofop is a selective, post-emergence herbicide used for the control of annual and perennial grasses in a wide range of broadleaf crops. It is a member of the aryloxyphenoxypropionate (AOPP) group of herbicides, which also includes fenoxaprop, haloxyfop, and diclofop.

Chemistry

Quizalofop is an organic compound that is a derivative of phenoxypropionic acid. Its chemical formula is C19H17ClN2O4. It is a white crystalline solid at room temperature. The compound is non-volatile and has a low solubility in water.

Mode of Action

Quizalofop works by inhibiting the enzyme Acetyl-CoA carboxylase (ACCase), which is essential for lipid biosynthesis in plants. This inhibition disrupts the plant's growth and development, leading to its death. Quizalofop is selective for grasses because it is rapidly metabolized and deactivated in broadleaf plants.

Usage

Quizalofop is used in a variety of broadleaf crops, including soybeans, cotton, sunflowers, and peanuts. It is applied post-emergence, meaning after the weeds have sprouted. It is most effective when applied to young, actively growing weeds.

Safety and Environmental Impact

Quizalofop has a low toxicity to mammals and is considered safe for use around humans when used properly. However, it is toxic to aquatic organisms and should not be applied near water sources. It is also toxic to some non-target plants, particularly grasses.

Resistance

Resistance to quizalofop and other AOPP herbicides has been reported in several grass species. This resistance is typically due to a mutation in the ACCase gene that prevents the herbicide from binding to the enzyme.