Glufosinate
Encyclopedia
Glufosinate or its ammonium salt DL-phosphinothricin
is an active ingredient in several nonselective systemic herbicide
s - Basta, Rely, Finale, Ignite
, Challenge and Liberty. It interferes with the biosynthetic pathway of the amino acid glutamine
and with ammonia
detoxification.
Some plants have been genetically modified for resistance to glufosinate. The gene which gives resistance to glufosinate is a bar or pat gene which was first isolated from two species of Streptomyces
bacteria. There are glufosinate-resistant transgenic varieties of several crops, including cotton
, canola
, corn
, soybean
, sugarbeet, and rice
. Of these, only canola, cotton and maize are currently on the market. This includes Bayer
's LibertyLink genes, used in over 100 hybrids.
Glufosinate was included in a biocide ban proposed by the Swedish Chemicals Agency and approved by the European Parliament on January 13, 2009.
's hugely successful Roundup Ready crops, Bayer Crop Science released its own herbicide tolerant crops. The range of crops tolerant to the herbicide glufosinate include cotton, soybean, canola and corn. These crops are also known as Liberty Link crops.
One advantage to producing Liberty Link crops is that any glyphosate resistance encountered in problematic weeds, such as rye grass, is overcome due to glufosinate having a completely different mode of action.
inhibitor
that binds to the glutamate site. Glufosinate-treated plants die due to a buildup of ammonia
and a cessation of photosynthesis
due to lack of glutamine
.
DL-Phosphinotricin
DL-Phosphinothricin is a herbicide commonly used in plant molecular biology and plant tissue culture. It is the ammonium salt of glufosinate. It is also known as glufosinate ammonium....
is an active ingredient in several nonselective systemic herbicide
Herbicide
Herbicides, also commonly known as weedkillers, are pesticides used to kill unwanted plants. Selective herbicides kill specific targets while leaving the desired crop relatively unharmed. Some of these act by interfering with the growth of the weed and are often synthetic "imitations" of plant...
s - Basta, Rely, Finale, Ignite
Ignite Herbicide
Ignite Herbicide is a herbicide developed by Bayer Cropscience for use with Liberty Link crops. it is advertised as the only non-selective alternative to Glyphosate....
, Challenge and Liberty. It interferes with the biosynthetic pathway of the amino acid glutamine
Glutamine
Glutamine is one of the 20 amino acids encoded by the standard genetic code. It is not recognized as an essential amino acid but may become conditionally essential in certain situations, including intensive athletic training or certain gastrointestinal disorders...
and with ammonia
Ammonia
Ammonia is a compound of nitrogen and hydrogen with the formula . It is a colourless gas with a characteristic pungent odour. Ammonia contributes significantly to the nutritional needs of terrestrial organisms by serving as a precursor to food and fertilizers. Ammonia, either directly or...
detoxification.
Some plants have been genetically modified for resistance to glufosinate. The gene which gives resistance to glufosinate is a bar or pat gene which was first isolated from two species of Streptomyces
Streptomyces
Streptomyces is the largest genus of Actinobacteria and the type genus of the family Streptomycetaceae. Over 500 species of Streptomyces bacteria have been described. As with the other Actinobacteria, streptomycetes are gram-positive, and have genomes with high guanine and cytosine content...
bacteria. There are glufosinate-resistant transgenic varieties of several crops, including cotton
Cotton
Cotton is a soft, fluffy staple fiber that grows in a boll, or protective capsule, around the seeds of cotton plants of the genus Gossypium. The fiber is almost pure cellulose. The botanical purpose of cotton fiber is to aid in seed dispersal....
, canola
Canola
Canola refers to a cultivar of either Rapeseed or Field Mustard . Its seeds are used to produce edible oil suitable for consumption by humans and livestock. The oil is also suitable for use as biodiesel.Originally, Canola was bred naturally from rapeseed in Canada by Keith Downey and Baldur R...
, corn
Maize
Maize known in many English-speaking countries as corn or mielie/mealie, is a grain domesticated by indigenous peoples in Mesoamerica in prehistoric times. The leafy stalk produces ears which contain seeds called kernels. Though technically a grain, maize kernels are used in cooking as a vegetable...
, soybean
Soybean
The soybean or soya bean is a species of legume native to East Asia, widely grown for its edible bean which has numerous uses...
, sugarbeet, and rice
Rice
Rice is the seed of the monocot plants Oryza sativa or Oryza glaberrima . As a cereal grain, it is the most important staple food for a large part of the world's human population, especially in East Asia, Southeast Asia, South Asia, the Middle East, and the West Indies...
. Of these, only canola, cotton and maize are currently on the market. This includes Bayer
Bayer
Bayer AG is a chemical and pharmaceutical company founded in Barmen , Germany in 1863. It is headquartered in Leverkusen, North Rhine-Westphalia, Germany and well known for its original brand of aspirin.-History:...
's LibertyLink genes, used in over 100 hybrids.
Glufosinate was included in a biocide ban proposed by the Swedish Chemicals Agency and approved by the European Parliament on January 13, 2009.
Liberty Link crops
In response to MonsantoMonsanto
The Monsanto Company is a US-based multinational agricultural biotechnology corporation. It is the world's leading producer of the herbicide glyphosate, marketed in the "Roundup" brand of herbicides, and in other brands...
's hugely successful Roundup Ready crops, Bayer Crop Science released its own herbicide tolerant crops. The range of crops tolerant to the herbicide glufosinate include cotton, soybean, canola and corn. These crops are also known as Liberty Link crops.
One advantage to producing Liberty Link crops is that any glyphosate resistance encountered in problematic weeds, such as rye grass, is overcome due to glufosinate having a completely different mode of action.
Mode of action
Phosphinothricin is an glutamine synthetaseGlutamine synthetase
Glutamine synthetase is an enzyme that plays an essential role in the metabolism of nitrogen by catalyzing the condensation of glutamate and ammonia to form glutamine:Glutamate + ATP + NH3 → Glutamine + ADP + phosphate...
inhibitor
Enzyme inhibitor
An enzyme inhibitor is a molecule that binds to enzymes and decreases their activity. Since blocking an enzyme's activity can kill a pathogen or correct a metabolic imbalance, many drugs are enzyme inhibitors. They are also used as herbicides and pesticides...
that binds to the glutamate site. Glufosinate-treated plants die due to a buildup of ammonia
Ammonia
Ammonia is a compound of nitrogen and hydrogen with the formula . It is a colourless gas with a characteristic pungent odour. Ammonia contributes significantly to the nutritional needs of terrestrial organisms by serving as a precursor to food and fertilizers. Ammonia, either directly or...
and a cessation of photosynthesis
Photosynthesis
Photosynthesis is a chemical process that converts carbon dioxide into organic compounds, especially sugars, using the energy from sunlight. Photosynthesis occurs in plants, algae, and many species of bacteria, but not in archaea. Photosynthetic organisms are called photoautotrophs, since they can...
due to lack of glutamine
Glutamine
Glutamine is one of the 20 amino acids encoded by the standard genetic code. It is not recognized as an essential amino acid but may become conditionally essential in certain situations, including intensive athletic training or certain gastrointestinal disorders...
.