Norflurazon

Suba, J.D. and Essington, M.E. Adsorption of fluometuron and norflurazon effect of tillage and dissolved organic carbon. Soil Sci, 164(3) 145-155, 1999. 

The molecular target site of triketone herbicides is the enzyme -hydroxyphenylpyruvate dioxygenase (HPPD). Inhibition of this enzyme disrupts the biosynthesis of carotenoids and causes a bleaching (loss of chlorophyll) effect on the foliage similar to that observed with inhibitors ofphytoene desaturase (e.g. norflurazon). However, the mechanism of action of HPPD inhibitors is different. Inhibtion of HPPD stops the synthesis of homogen tisate (HGA), which is a key precursor of the 8 different tocochromanols (tocopherols and tocotrienols) and prenyl quinones. In the absence of prenylquinone plastoquinone, phytoene desaturase activity is interrupted. The bleaching of the green tissues ensues as if these compounds inhibited phytoene desaturase. 

Substitution of a trifluoromethyl group in the 3-position of the benzene ring and alkylation of the 4-amino group, as in norflurazon (16) (69FRP1575643), turns the pyridazin-3-ones into inhibitors of carotenoid biosynthesis. A similar substitution pattern occurs in fluridone (17) (74GEP2537753). The long-established l,2,4-triazol-3-ylamine, known as amitrole, and... 

Norflurazon herbicide Methanol Filtration Cis high-performance liquid chromatography [76]... 

Achhireddy, N.R. and M. Singh. (1986). Toxicity, uptake, translocation, and metabolism of norflurazon in five citrus rootstocks. Weed Sci., 34 312-317. 

Sandman, G., P.M. Brantley, and P. Boger. (1980). The inhibitory mode of action of pyridazinone herbicide norflurazon on cell-free carotenogenic enzyme system. Pestic. Biochem.Physiol., 14 185-191. 

Singh, M., W.S. Castle, and N.R. Achhireddy (1985). Movement of bromacil and norflurazon in sandy soil in Florida. Bull. Environ. Contam. Toxicol., 35 279-284. 

Chemicals such as simazine are used alone as herbicides, or more often in combination with other herbicides such as oxyfluorfen, oryzalin, or norflurazon, generally in four- to six-foot (1.2-2.0 meter (m)) strips down the tree row. The centers are either tilled or mowed parallel with the tree row. In order for strip chemical treatment to be successful, it is essential to eradicate perennial weeds by the use of repeated postemergence herbicide applications and tillage. 

A variety of herbicides have been used in combination with simazine and other triazines. These herbicides have preemergence and postemergence activity and are primarily effective on grass and perennial weeds. The preemergence herbicides used in combinations with simazine include oryzalin, pendimethalin, prodiamine, norflurazon, oxy-fluorfen, and diuron. Glyphosate, oxyfluorfen, paraquat, and amino triazole (used in some parts of the world) are... 

Oxyfluorfen, oryzalin, napropamide, and norflurazon are additional weed control tools developed for peach crops. In California approximately 23 000 pounds of simazine were applied to 33 000 A of peaches and nectarines in 2004. 

Simazine is an important weed control tool in cherry (Gilbert et al, 1965 Anderson, 1989) and in apricot. A combination of simazine and either oryzalin, norflurazon, or oxyfluorfen showed excellent weed control in sour cherry with no tree injury (Anderson, 1989). In California approximately 150 pounds of simazine were applied to 200A of cherry and apricot crops in 2004. 

Alva, A.K. and M. Singh (1990). Sorption of bromacil, diuron, norflurazon, and simazine at various horizons in two soils. Bull. Environ. Contam. Toxicol., 45 365-374. 

Hubbs, C.W. and T.L. Lavy (1990). Dissipation of norflurazon and other persistent herbicides in soil. Weed Sci., 38 81-88. 

During the summer of 1997, water samples were collected and analyzed for herbicides from 32 Playa Lakes of the High Plains that receive drainage from both cotton and corn agriculture in West Texas (Figure 30.1). The major cotton herbicides detected in the water samples were diuron, fluometuron, metolachlor, norflurazon, and prometryn. Atrazine and propazine also were routinely detected in samples from the Playa Lakes. 

Common Name Norflurazon Synonym Zorial, Solicam, Evital, Telok... 

Massad, W., Criado, S., Bertolotti, S., Pajares, A., Gianotte, J., Escalada, J.P., Amat-Guerri, F., Carcia, N.A. (2004) Photodegradation of the herbicide norflurazon sensitised by riboflavin. A kinetic and mechanistic study. Chemosphere 57, 455—461. 

Phytoene desaturase bleaching herbicides. Bleaching herbicides inhibit the synthesis of carotenoids in plants [30,31], A number of phytoene desaturase herbicides such as norflurazon (Solicam , Zorial ), flurochloridone (Racer ), fluri-done (Sonar ), and diflufenican (Fenican , Legacy ) have been commercialized. 

Trifluoromethylaniline, directly or indirectly, is the starting material for the synthesis of all four of the herbicides norflurazon, flurochloridone, fluridone, and diflufenican. Norflurazon is prepared from 3-trifluoromethylphenyl hydrazine, which is obtained from the diazotization and reduction of 3-trifluoromethylaniline [35], Diflufenican is prepared from the reaction of 3-trifluoromethylphenol and... 

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