1963 Mar 26; 157:332–345. For example, “Group 1” herbicides are ACCase inhibitors and “Group 2” herbicides are ALS inhibitors. TOXICOLOGY 7.1 Mode of Action It is now well established that "Redox Cycling" is the primary reaction responsible for the toxicity of paraquat.

Paraquat causes toxic chemical reactions to occur throughout many parts of the body, primarily the lungs, liver, and kidneys. These numbers refer to a specific mode of action and were developed to consistently organize herbicides based on their mode of action. Proc R Soc Lond B Biol Sci. 1970 Jul;118(3):43P-44P.

" Paraquat is the trade name for N, N -dimethyl-4, 4 -bipyridinium dichloride, one of the most widely used herbicides in the world. Paraquat acts in the presence of light to desiccate the green parts of all plants with which it comes into contact. Paraquat has been banned, or use disallowed, in 32 countries (including the countries of the Prepared by Meriel Watts PhD February, 2011 Contents Summary 1. action and were developed to consistently organize herbicides Knowing and understanding each herbicide’s mode of action is an important step in selecting the proper herbicide for each crop, diagnosing herbicide injury, and designing a Author(s) : Dodge, A. D.; Harris, N. Author Affiliation : Sch. However, glyphosate is a highly selective herbicide when used in conjunction with crops that have been genetically ... used. Sci., Bath Univ. The mechanism of cyclic phosphorylation by illuminated chloroplasts. The science of paraquat. Paraquat, a viologen, is quick-acting and non-selective, killing green plant tissue on contact. Environmental Fate - Ecotoxicology - Human Health - A to Z Index - Home . The mode-of-action is the overall manner in which a herbicide affects a plant at the tissue or cellular level. Mode of Action. The hazards of paraquat through various routes of exposure are well recognized and exposure by ingestion is known to result in pulmonary fibrosis due to selective accumulation in the lung (Dinis-Oliveira et al., 2008). 1971 Sep;30(111):130-5. [ edit ] i have read that paraquat only reacts on the green parts of plants and not roots and woody stems. 7.

Some may not be the cause of paraquat poisoning but the result or an accompanying phenomenon of paraquat action. [Zweig G, Shavit N, Avron M. Diquat (I,I'-ethylene-2,2'-dipyridylium dibromide) in photo-reactions of isolated chloroplasts. In anaerobic conditions the paraquat cation can be reduced by NADPH-dependant microsomal flavoprotein reductase to form the reduced radical. 20 MODE OF ACTION: Contact, post emergent.

Herbicide Mode of Action. Acute paraquat poisoning seems to be very complex because many possible mechanisms of paraquat cytotoxicity have been reported. Herbicides with the same mode-of- action will have the same translocation (movement) pattern and produce similar injury symptoms. 1. the article mentions a superoxide radical that can attack unsaturated membrane lipids. PMID: 4110469 [Indexed for MEDLINE] Paraquat, a fast-acting, nonselective herbicide, is widely used in agriculture worldwide. Dodge AD, Harris N. PMCID: PMC1179226 PMID: 5472170 [PubMed - indexed for MEDLINE] Uptake and translocation: Not significantly translocated because in the presence of sunlight it quickly destroys conducting tissue. At night it may passively move through the plant. Herbicide Mode of Action How a herbicide works Use herbicides more efficiently Recognize and diagnose injury problems Herbicide resistance management.