Herbicides: Pesticides used to destroy unwanted vegetation, especially various types of weeds, grasses (POACEAE), and woody plants. Some plants develop HERBICIDE RESISTANCE.Herbicide Resistance: Diminished or failed response of PLANTS to HERBICIDES.Atrazine: A selective triazine herbicide. Inhalation hazard is low and there are no apparent skin manifestations or other toxicity in humans. Acutely poisoned sheep and cattle may show muscular spasms, fasciculations, stiff gait, increased respiratory rates, adrenal degeneration, and congestion of the lungs, liver, and kidneys. (From The Merck Index, 11th ed)2,4-Dichlorophenoxyacetic Acid: An herbicide with irritant effects on the eye and the gastrointestinal system.2-Methyl-4-chlorophenoxyacetic Acid: A powerful herbicide used as a selective weed killer.Linuron: A selective pre- and post-emergence herbicide. (From Merck Index, 11th ed)Plant Weeds: A plant growing in a location where it is not wanted, often competing with cultivated plants.2,4,5-Trichlorophenoxyacetic Acid: An herbicide with strong irritant properties. Use of this compound on rice fields, orchards, sugarcane, rangeland, and other noncrop sites was terminated by the EPA in 1985. (From Merck Index, 11th ed)Acetolactate Synthase: A flavoprotein enzyme that catalyzes the formation of acetolactate from 2 moles of PYRUVATE in the biosynthesis of VALINE and the formation of acetohydroxybutyrate from pyruvate and alpha-ketobutyrate in the biosynthesis of ISOLEUCINE. This enzyme was formerly listed as EC 126.96.36.199.Trifluralin: A microtubule-disrupting pre-emergence herbicide.Simazine: A triazine herbicide.3-Phosphoshikimate 1-Carboxyvinyltransferase: An enzyme of the shikimate pathway of AROMATIC AMINO ACID biosynthesis, it generates 5-enolpyruvylshikimate 3-phosphate and ORTHOPHOSPHATE from PHOSPHOENOLPYRUVATE and shikimate-3-phosphate. The shikimate pathway is present in BACTERIA and PLANTS but not in MAMMALS.Weed Control: The prevention of growth and or spread of unwanted plants.Paraquat: A poisonous dipyridilium compound used as contact herbicide. Contact with concentrated solutions causes irritation of the skin, cracking and shedding of the nails, and delayed healing of cuts and wounds.Picloram: A picolinic acid derivative that is used as a herbicide.Dicamba: A chlorinated organic herbicide.Protoporphyrinogen Oxidase: A membrane-bound flavoenzyme that catalyzes the oxygen-dependent aromatization of protoporphyrinogen IX (Protogen) to protoporphyrin IX (Proto IX). It is the last enzyme of the common branch of the HEME and CHLOROPHYLL pathways in plants, and is the molecular target of diphenyl ether-type herbicides. VARIEGATE PORPHYRIA is an autosomal dominant disorder associated with deficiency of protoporphyrinogen oxidase.Diuron: A pre-emergent herbicide.Triazines: Heterocyclic rings containing three nitrogen atoms, commonly in 1,2,4 or 1,3,5 or 2,4,6 formats. Some are used as HERBICIDES.Lolium: Common member of the Gramineae family used as cattle FODDER. It harbors several fungi and other parasites toxic to livestock and people and produces allergenic compounds, especially in its pollen. The most commonly seen varieties are L. perenne, L. multiflorum, and L. rigidum.Delftia acidovorans: A species of gram-negative rod-shaped bacteria found ubiquitously and formerly called Comamonas acidovorans and Pseudomonas acidovorans. It is the type species of the genus DELFTIA.ToluidinesDefoliants, Chemical: Herbicides that remove leaves from trees and growing plants. They may be either organic or inorganic. Several of the more persistent types have been used in military operations and many are toxic. (From Hawley's Condensed Chemical Dictionary, 11th ed)Chlorophenols: Phenols substituted with one or more chlorine atoms in any position.Pesticides: Chemicals used to destroy pests of any sort. The concept includes fungicides (FUNGICIDES, INDUSTRIAL); INSECTICIDES; RODENTICIDES; etc.Sulfonylurea CompoundsAminobutyrates: Derivatives of BUTYRIC ACID that contain one or more amino groups attached to the aliphatic structure. Included under this heading are a broad variety of acid forms, salts, esters, and amides that include the aminobutryrate structure.Agriculture: The science, art or practice of cultivating soil, producing crops, and raising livestock.4-Hydroxyphenylpyruvate Dioxygenase: An enzyme that catalyzes the conversion of 4-hydroxyphenylpyruvate plus oxygen to homogentisic acid and carbon dioxide. EC 188.8.131.52.Methylurea Compounds: Urea compounds which are substituted with one or more methyl groups.Propanil: A chlorinated anilide that is used as an herbicide.Phenyl Ethers: Ethers that are linked to a benzene ring structure.Agrochemicals: Chemicals used in agriculture. These include pesticides, fumigants, fertilizers, plant hormones, steroids, antibiotics, mycotoxins, etc.Diquat: A contact herbicide used also to produce desiccation and defoliation. (From Merck Index, 11th ed)Plants, Genetically Modified: PLANTS, or their progeny, whose GENOME has been altered by GENETIC ENGINEERING.Pesticide Residues: Pesticides or their breakdown products remaining in the environment following their normal use or accidental contamination.Glycine: A non-essential amino acid. It is found primarily in gelatin and silk fibroin and used therapeutically as a nutrient. It is also a fast inhibitory neurotransmitter.Agricultural Workers' Diseases: Diseases in persons engaged in cultivating and tilling soil, growing plants, harvesting crops, raising livestock, or otherwise engaged in husbandry and farming. The diseases are not restricted to farmers in the sense of those who perform conventional farm chores: the heading applies also to those engaged in the individual activities named above, as in those only gathering harvest or in those only dusting crops.Heterocyclic Compounds, 2-Ring: A class of organic compounds containing two ring structures, one of which is made up of more than one kind of atom, usually carbon plus another atom. The heterocycle may be either aromatic or nonaromatic.Crops, Agricultural: Cultivated plants or agricultural produce such as grain, vegetables, or fruit. (From American Heritage Dictionary, 1982)Water Pollutants, Chemical: Chemical compounds which pollute the water of rivers, streams, lakes, the sea, reservoirs, or other bodies of water.Fungicides, Industrial: Chemicals that kill or inhibit the growth of fungi in agricultural applications, on wood, plastics, or other materials, in swimming pools, etc.Biodegradation, Environmental: Elimination of ENVIRONMENTAL POLLUTANTS; PESTICIDES and other waste using living organisms, usually involving intervention of environmental or sanitation engineers.Glycolates: Derivatives of ACETIC ACID which contain an hydroxy group attached to the methyl carbon.Cyclohexanones: Cyclohexane ring substituted by one or more ketones in any position.Amaranthus: A plant genus, in the family AMARANTHACEAE, best known as a source of high-protein grain crops and of Red Dye No. 2 (AMARANTH DYE). Tumbleweed sometimes refers to Amaranthus but more often refers to SALSOLA.Soil Pollutants: Substances which pollute the soil. Use for soil pollutants in general or for which there is no specific heading.Acetamides: Derivatives of acetamide that are used as solvents, as mild irritants, and in organic synthesis.Drug Resistance: Diminished or failed response of an organism, disease or tissue to the intended effectiveness of a chemical or drug. It should be differentiated from DRUG TOLERANCE which is the progressive diminution of the susceptibility of a human or animal to the effects of a drug, as a result of continued administration.Acetyl-CoA Carboxylase: A carboxylating enzyme that catalyzes the conversion of ATP, acetyl-CoA, and HCO3- to ADP, orthophosphate, and malonyl-CoA. It is a biotinyl-protein that also catalyzes transcarboxylation. The plant enzyme also carboxylates propanoyl-CoA and butanoyl-CoA (From Enzyme Nomenclature, 1992) EC 184.108.40.206.Alismatidae: A plant subclass of the class Liliopsida (monocotyledons) in the Chronquist classification system. This is equivalent to the Alismatales order in the APG classification system. It is a primitive group of more or less aquatic plants.Oxidoreductases Acting on CH-CH Group Donors: A subclass of enzymes which includes all dehydrogenases acting on carbon-carbon bonds. This enzyme group includes all the enzymes that introduce double bonds into substrates by direct dehydrogenation of carbon-carbon single bonds.