Bifenox

Bifenox is a selective contact herbicide used to control broad-leaved weeds and grasses in a variety of crops, including cereals, fruits, vegetables, and vines. It is a member of the diphenyl ether group of herbicides, which also includes acifluorfen and oxyfluorfen. Bifenox works by inhibiting the enzyme protoporphyrinogen oxidase, which is involved in the synthesis of chlorophyll.

Chemistry

Bifenox is a synthetic compound derived from phenol. It is a white crystalline solid with a slight phenolic odor. It is non-corrosive and non-flammable. Bifenox is soluble in most organic solvents, but only slightly soluble in water.

Mode of Action

Bifenox acts as a contact herbicide, meaning it only affects the parts of the plant that it comes into contact with. It works by inhibiting the enzyme protoporphyrinogen oxidase, which is involved in the synthesis of chlorophyll. This inhibition leads to the accumulation of protoporphyrin IX, a compound that is toxic to plants when exposed to light. This causes cell membranes to rupture and the plant to die.

Use and Application

Bifenox is used to control a wide range of broad-leaved weeds and grasses in a variety of crops, including cereals, fruits, vegetables, and vines. It is typically applied as a pre-emergence or early post-emergence treatment. The exact rate and timing of application can vary depending on the specific crop and weed species.

Safety and Environmental Impact

Bifenox is moderately toxic to mammals and birds, but is highly toxic to fish and aquatic invertebrates. It is not considered to be a carcinogen or a mutagen. Bifenox is not persistent in the environment and is rapidly degraded by soil microorganisms.

Regulation

In the European Union, bifenox has been banned since 2009 due to concerns about its toxicity to aquatic organisms and potential for groundwater contamination. However, it is still registered for use in several other countries, including the United States and Australia.