Glufosinate

Glufosinate is a naturally occurring broad-spectrum herbicide produced by several species of Streptomyces bacteria. It is used to control a wide range of weeds after the crop emerges or for total vegetation control on land not used for cultivation. Glufosinate herbicides are also used to regulate growth and for desiccation of a wide variety of crops.

Chemistry

Glufosinate is a phosphinic acid, specifically DL-phosphinothricin. It is a structural analogue of the natural amino acid glutamic acid, which plays a key role in the metabolism of most organisms, including plants.

Mode of action

Glufosinate acts by inhibiting the enzyme glutamine synthetase, which is necessary for the synthesis of glutamine and for ammonia detoxification, leading to a lethal accumulation of ammonia in plant tissues. The inhibition of this enzyme also disrupts the process of photosynthesis, leading to the death of the plant.

Usage

Glufosinate is used in agriculture for weed control, and is especially effective against perennial weeds. It is also used in combination with genetically modified crops that have been engineered to resist the effects of glufosinate.

Safety

The World Health Organization has classified glufosinate as "not likely to be carcinogenic to humans". However, it can cause irritation to the eyes and skin, and may cause other health effects if inhaled or ingested.

Environmental impact

Glufosinate is highly toxic to a variety of organisms, including several species of fish and aquatic invertebrates. It also has the potential to contaminate surface waters through runoff.

See also

• Herbicide
• Genetically modified crops
• Weed control