Herbicides

thumb|A field after application of a herbicide thumb|Weeds controlled with herbicide

chemical compound

Glyphosate (IUPAC name: '''N-(phosphonomethyl)glycine') is a broad-spectrum systemic herbicide and crop desiccant. It is an organophosphorus compound, specifically a phosphonate, which acts by inhibiting the plant enzyme 5-enolpyruvylshikimate-3-phosphate synthase (EPSP). Glyphosate-based herbicides (GBHs) are used to kill weeds, especially annual broadleaf weeds and grasses that compete with crops. American agricultural company Monsanto brought it to market for agricultural use in 1974 under the trade name Roundup''. Monsanto's last commercially relevant United States patent expired in 2000.

Paraquat (trivial name; ), or '''N,N′-dimethyl-4,4′-bipyridinium dichloride (systematic name), also known as methyl viologen''', is a toxic organic compound with the chemical formula [(C6H7N)2]Cl2. It is classified as a viologen, a family of redox-active heterocycles of similar structure. It is one of the most widely used herbicides worldwide. It is quick-acting and non-selective, killing green plant tissue on contact.

thumb|281x281px|Defoliants are used as an aid in the harvesting of certain crops such as cotton. thumb|2,4-D, one of the first chemical herbicides used as a defoliant.|281x281px thumb|U.S. Army Huey helicopter spraying [[Agent Orange over agricultural land during the Vietnam War.|283x283px]]

Atrazine ( ) is a chlorinated herbicide of the triazine class. It is used to prevent pre-emergence broadleaf weeds in crops such as maize (corn), soybean and sugarcane, and also in turf landscaping, such as golf courses and residential lawns. Its use significantly increases crop yields. Atrazine is one of the most widely used herbicides in the United States, Canada, Australia, and Brazil, but has been banned in other countries including in the European Union and the Gulf Cooperation Council. Its use is controversial and highly regulated.

chemical compound

Chloropicrin, also known as PS (from Port Sunlight) and nitrochloroform, is a chemical compound currently used as a broad-spectrum antimicrobial, fungicide, herbicide, insecticide, and nematicide. It was used as a poison gas in World War I and the Russian military has been accused of using it in the Russo-Ukrainian War. Its chemical structural formula is .

Juglone, also called 5-hydroxy-1,4-naphthalenedione (IUPAC) is a phenolic organic compound with the molecular formula C10H6O3. In the food industry, juglone is also known as C.I. Natural Brown 7 and C.I. 75500. It is insoluble in benzene but soluble in dioxane, from which it crystallizes as yellow needles. It is an isomer of lawsone, which is the active dye compound in the henna leaf.

thumb|3-Amino-1,2,4-triazole in powder form 3-Amino-1,2,4-triazole (3-AT) is a heterocyclic organic compound that consists of 1,2,4-triazole with an amino group as a substituent.

DCMU (3-(3,4-dichlorophenyl)-1,1-dimethylurea) is an algicide and herbicide of the aryl urea class that inhibits photosynthesis. It was introduced by Bayer in 1954 under the trade name of Diuron. ==History== In 1952, chemists at E. I. du Pont de Nemours and Company patented a series of aryl urea derivatives as herbicides. Several compounds covered by this patent were commercialized as herbicides: chlortoluron (3-chloro-4-methylphenyl) and DCMU, the (3,4-dichlorophenyl) example. Subsequently, over thirty related urea analogs with the same mechanism of action reached the market worldwide. ==Synt

Picloram is a systemic herbicide used for general woody plant control. It also controls a wide range of broad-leaved weeds, but most grasses are resistant. A chlorinated derivative of picolinic acid, picloram is in the pyridine family of herbicides.

Diquat is the ISO common name for an organic dication that, as a salt with counterions such as bromide or chloride is used as a contact herbicide that produces desiccation and defoliation. Diquat is no longer approved for use in the European Union, although its registration in many other countries including the USA is still valid.

thumb|A person mixing Lasso - A brand of alachlor made by Monsanto

Chloroacetamide (2-chloroacetamide) is a chlorinated organic compound with the molecular formula . It is a colorless solid although older samples appear yellow. It has a characteristic odor and is readily soluble in water. It has the structure .

Trifluralin is a common preëmergent selective herbicide, a dinitroaniline. With about used in the United States in 2001, and in 2012, it is one of the most widely used herbicides. Trifluralin is also used in Australia, New Zealand, Iran, India, Brazil and previously in the EU. Introduced in 1964, Trifluralin was the first organofluorine compound used as an agrochemical.

Glufosinate (also known as phosphinothricin and often sold as an ammonium salt) is a naturally occurring broad-spectrum herbicide produced by several species of Streptomyces soil bacteria. Glufosinate is a non-selective, contact herbicide, with some systemic action. Plants may also metabolize bialaphos and phosalacine, other naturally occurring herbicides, directly into glufosinate. The compound irreversibly inhibits glutamine synthetase, an enzyme necessary for the production of glutamine and for ammonia detoxification, giving it antibacterial, antifungal and herbicidal properties. Applicatio

chemical compound

trademark of glyphosate-based herbicide made by Monsanto

Acetochlor is an herbicide developed by Monsanto Company and Zeneca. It is a member of the class of herbicides known as chloroacetanilides. Its mode of action is elongase inhibition, and inhibition of geranylgeranyl pyrophosphate (GGPP) cyclization enzymes, part of the gibberellin pathway. It carries high risks of environmental contamination. ==Manufacture== Acetochlor is manufactured in two steps from 2-ethyl-6-methylaniline. A reaction with chloroacetyl chloride gives an anilide which is treated with chloromethyl ethyl ether and sodium hydroxide to form the herbicide. 550px

Dinoseb is a common industry name for 6-sec-butyl-2,4-dinitrophenol, a herbicide in the dinitrophenol family. It is a crystalline orange solid which does not readily dissolve in water. Dinoseb is banned as an herbicide in the European Union (EU) and the United States because of its toxicity.

Butachlor is a herbicide of the acetanilide class. It is used as a selective pre-emergent herbicide to control annual grasses and some broad-leaved weeds. It was introduced circa 1970. It is extensively used in India in the form of granules and emulsifiable concentrate in rice as post emergence herbicide, and was sold in India in 2005-06, declining to in 2009-10.

Nitrofen is an herbicide of the diphenyl ether class. Because of concerns about its carcinogenicity, the use of nitrofen has been banned in the European Union and in the United States since 1996. It has been superseded by related protoporphyrinogen oxidase enzyme inhibitors including acifluorfen and fomesafen.

Imazapyr is a non-selective herbicide used for the control of a broad range of weeds including terrestrial annual and perennial grasses and broadleaved herbs, woody species, and riparian and emergent aquatic species.

Bromoxynil is an organic compound with the formula HOBr2C6H2CN. It is classified as a nitrile herbicide, and as such sold under many trade names. It is a white solid. It works by inhibiting photosynthesis. It is moderately toxic to mammals.

2,6-Dichlorobenzonitrile (DCBN or dichlobenil) is an organic compound with the chemical formula C6H3Cl2CN. It is a white solid soluble in organic solvents. It is widely used as a herbicide and organic chemistry building block.

Propanil is a widely used contact herbicide. With an estimated use of about 8 million pounds in 2001, it is one of the more widely used herbicides in the United States. Propanil is said to be in use in approximately 400,000 acres of rice production each year. Propanil was introduced in 1960. It is also used in Australia,, India and Uganda.

Hexazinone is an organic compound that is used as a broad spectrum herbicide. It is a colorless solid. It exhibits some solubility in water but is highly soluble in most organic solvents except alkanes. A member of the triazine class herbicides, it is manufactured by DuPont and sold under the trade name Velpar.

Simazine is an herbicide of the triazine class. The compound is used to control broad-leaved weeds and annual grasses.

Bromacil is an organic compound with the chemical formula C9H13BrN2O2, commercially available as a herbicide. Bromacil was first registered as a pesticide in the U.S. in 1961, and by 1974 was used annually in the US, largely by government and industry. It is used for brush control on non-cropland areas. It works by interfering with photosynthesis by entering the plant through the root zone and moving throughout the plant. Bromacil is one of a group of compounds called substituted uracils. These materials are broad spectrum herbicides used for nonselective weed and brush control on non-cropland

MPP+ (1-methyl-4-phenylpyridinium) or cyperquat is a positively charged organic molecule with the chemical formula C12H12N+. It is a monoaminergic neurotoxin that acts by interfering with oxidative phosphorylation in mitochondria by inhibiting complex I, leading to the depletion of ATP and eventual cell death.

Clomazone is an agricultural herbicide, and has been the active ingredient of products named Command and Commence. The molecule consists of a 2-chlorobenzyl group bound to a nitrogen-oxygen heterocycle called a isoxazolidinone. It is a white solid.

Asulam is a herbicide invented by May & Baker Ltd, internally called M&B9057, that is used in horticulture and agriculture to kill bracken and docks. It is also used as an antiviral agent. It is currently marketed, by United Phosphorus Ltd - UPL, as "Asulox" which contains 400 g/L of asulam sodium salt.

Metribuzin ('4-amino-6-tert-butyl-3-(methylthio)-1,2,4-triazin-5(4H)-one') is a herbicide used both pre- and post-emergently in crops including soy bean, potatoes, tomatoes, barley, chickpeas, faba beans, lupins, lentils, vetch, blade wheat and sugar cane.

Mesotrione is a selective herbicide used mainly in maize crops and has also been shown to have weak insecticidal properties. It is a synthetic compound inspired by the natural substance leptospermone found in the bottlebrush tree Callistemon citrinus. It inhibits the enzyme 4-hydroxyphenylpyruvate dioxygenase (HPPD) and is sold under brand names including Callisto and Tenacity. It was first marketed by Syngenta in 2001.

Nitisinone, sold under the brand name Orfadin among others, is a medication used for the treatment of hereditary tyrosinemia type 1; or for the reduction of urine homogentisic acid in adults with alkaptonuria. Nitisinone is a hydroxyphenyl-pyruvate dioxygenase inhibitor.

Metolachlor is an organic compound that is widely used as an herbicide. It is a derivative of aniline and is a member of the chloroacetanilide family of herbicides. It is highly effective toward grasses.

chemical compound

Chlortoluron, chlorotoluron and CTU are the common names for an organic compound of the phenylurea class of herbicides used to control broadleaf and annual grass weeds in cereal crops.

Dazomet is a common soil fumigant that acts as a herbicide, fungicide, slimicide, and nematicide.

Chloroxuron is a phenylurea herbicide that appears as an odorless and colorless powder or white crystals. Phenylurea pesticides are characterized for their agricultural use to control weed growth, acting as photosynthesis inhibitors. These herbicides can either be endocrine disruptors, or have ecotoxic or genotoxic effects.

Bensulide is a selective organophosphate herbicide. It is one of a few organophosphate compounds that are used as an herbicide. Most of the others are used as insecticides. It is used on vegetable crops such as carrots, cucumbers, peppers, and melons and in cotton and turfgrass to control annual grasses such as bluegrass and crabgrass and broadleaf weeds. It is often applied before the weed seeds germinate (pre-emergence) in order to prevent them from germinating. It is available as granules or an emulsifiable concentrate. Estimates place the total use of bensulide in the United States at abou

Tebuthiuron is a nonselective broad spectrum herbicide of the urea class. It is used to control weeds, woody and herbaceous plants, and sugar cane. It is absorbed by the roots and transported to the leaves, where it inhibits photosynthesis. The ingredient was discovered by Air Products and Chemicals, but was registered by Elanco in the United States in 1974, and later sold to Dow AgroSciences.

Chlorthiamide is an organic compound with the chemical formula C7H5Cl2NS used as an herbicide.

Terbuthylazine is a selective herbicide. Chemically, it is a halogenated triazine; compared with atrazine (1958 inv., Geigy lab) and simazine, it has a tert-butyl group in place of the isopropyl and ethyl group, respectively. The sim-azine molecule with 2 ethyl groups is symmetric and flat (excepting its equal ends). The threefold substituted triazines have resonance of the free (non-bonding, \pi-) electron pairs, resulting in equivalent mesomeric structures.

Fluometuron is an herbicide. In the United States it was approved for use on cotton and sugarcane crops in 1974, but since 1986 is only approved for use on cotton.

Benfluralin (or Benefin) is a herbicide of the dinitroaniline class. The mechanism of action of benfluralin involves pre-emergent inhibition of mitosis, root and shoot development, same as trifluralin, from which benfluralin was developed in 1963. thumb|Shows states where benefin (as Balan DF) is registered (Green) or not (Red). Not shown: Hawaii, where it is registered.

Methazole (C9H6Cl2N2O3) is an obsolete herbicide in the family of herbicides known as oxadiazolones. It was used as a post-emergent treatment for controlling weeds.

Monolinuron is a pesticide, more specifically a selective systemic herbicide and an algaecide. As an herbicide, it is used to control broad-leaved weeds and annual grasses in vegetable crops such as leeks, potatoes, and dwarf French beans. Monolinuron affects the photosynthesis in weeds. Following uptake of monolinuron through roots and leaves of weeds, monolinuron causes early symptoms of yellowing and die-back of the leaves, eventually resulting in weed death. In fishkeeping, it is used to control blanket weed and hair algae.

Bentazon, or Bentazone, is a herbicide active ingredient. It is selective. Chemically, it is a thiadiazine. Sodium bentazon is available commercially as "Basagran", "Herbatox", "Leader" and "Laddock" and is coloued slightly brown.

Imazapic is a chemical used as an herbicide. It controls many broad leaf weeds and controls or suppresses some grasses in pasture, rangeland and certain types of turf. It has a half-life of around 120 days in soil. Imazapic is considered an environmental hazard due to its harmful effects on aquatic life.

Prometon is a herbicide for annual and perennial broad-leaf weed, brush and grass control mainly in non-cropping situations.

Dimethenamid is a widely used herbicide belonging to the chloroacetamide class (group 15). Group 15 herbicides inhibit synthesis of certain long-chain fatty acids, thus reducing plant growth. In 2001, about of dimethenamid were used in the United States. Dimethenamid is registered for control of annual grasses, certain annual broadleaf weeds and sedges in field corn, seed corn, popcorn and soybeans. Supplemental labeling also allows use on sweet corn, grain sorghum, dry beans and peanuts. In registering dimethinamide (SAN 582H/Frontier), EPA concluded that the primary means of dissipation of d

Benthiocarb is a thiocarbamate cholinesterase inhibitor used as an herbicide. Benthiocarb is almost always used to control the weeds around rice crops, but its effectiveness is not specific to just rice crops. The benthiocarb molecule is an organic molecule containing a phenol bonded to a chlorine atom.

Linuron is a phenylurea herbicide that is used to control the growth of grass and weeds for the purpose of supporting the growth of crops like soybeans. It is registered for use in India.

Bialaphos is a natural herbicide produced by the bacteria Streptomyces hygroscopicus and Streptomyces viridochromogenes. It is also known by the ISO common name bilanafos. Bialaphos is a protoxin and nontoxic as is. When it is metabolized by a plant, the glutamic acid analog glufosinate is released which inhibits glutamine synthetase. This results in the accumulation of ammonium and disruption of primary metabolism.

Propachlor (2-chloro-N-isopropylacetanilide) is an anilide used primarily as an herbicide first marketed by Monsanto under the tradename Ramrod. It was initially registered for use in the United States in 1964.

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chemical compound

Aclonifen is a diphenyl ether herbicide which has been used in agriculture since the 1980s. Its mode of action has been uncertain, with evidence suggesting it might interfere with carotenoid biosynthesis or inhibit the enzyme protoporphyrinogen oxidase (PPO). Both mechanisms could result in the observed whole-plant effect of bleaching (removal of leaf colour) and the compound includes chemical features (a nitro group attached to a diphenyl ether) that are known to result in PPO effects, as seen with acifluorfen, for example. In 2020, further research revealed that aclonifen has a different and