Plants organophosphorus compound

Diazinon (phosphorothioic acid 0,0-diethyl 0-(6-mcthyl-2-(l-mcthylcthyl)-4-pyrimidinyl) ester) is an organophosphorus compound with an anticholinesterase mode of action. It is used extensively to control hies, lice, insect pests of ornamental plants and food crops, as well as nematodes and soil insects in lawns and croplands. Diazinon degrades rapidly in the environment, with half-time persistence usually less than 14 days. But under conditions of low temperature, low moisture, high alkalinity, and lack of suitable microbial degraders, diazinon may remain biologically active in soils for 6 months or longer. 

An early method for the isolation of an organophosphorus compound from animal or plant tissues was based on extraction by hexane and selective partitioning with acetonit-... 

Plant enzymes do not catalyze the hydrolysis of organophosphorus compounds greatly, but they do catalyze their oxidation. Consequently, the oxidation products accumulate more in plants than in animals, but they appear to be generally the same as those produced by animals. 

It was not until the late 1960s that effective systemic fungicides appeared on the market, and their development represents an important breakthrough in the field of plant chemotherapy. The major classes of systemic fungicides developed since 1966 are oxathiins, benzimidazoles, thiophanates, and pyrimidines. Other effective systemic fungicides used currently include antibiotics, morpholines, organophosphorus compounds, and most recently, the sterol biosynthesis inhibitors, e.g., triazoles. 

Very little detail is known about the nitrogen and phosphorus cycles. Dissolved orthophosphate is taken up in plant growth and returned eventually after serving in cell fluids and tissues. It appears to be released primarily in the form of organophosphorus compounds, and at certain seasons of the year more than half the phosphorus in the water is described as "dissolved organic phosphorus. Yet as of a year or so ago... 

Key applications Pesticides, herbicides and plant growth regulators (carbamates, glyphosate, diquat/paraquat, pyrethrins, organophosphorus compounds) Industrial pollutants (dyes, surfactants, amines, PAHs, PCBs, dioxins, phenols, aldehydes)... 

Malathion is a widely used member of a class of pesticides known as organophospate derivatives. It is biodegradable and less toxic (LDg for female rats is 1000 mg/kg) than DDT. Several other organophosphorus compounds are modifications of this basic structure. They include dimethoate (LD = 387 mg/kg), chlorpyrifos (LD q = 95-270 mg/kg), and methyl parathion (LD o = 18 -50 mg/kg). These organophosphates often are used in the treatment of many pests that are found on vegetables, or, in the case of methyl parathion, on cotton plants. 

Organophosphorus compounds, many of which are derivatives of dialkyl H-phosphonates, represent one of the largest classes of pesticides currently in use. They are mainly applied as insecticides, fungicides, herbicides, and bactericides, and also as plant-growth regulators [1,2]. 

In addition to the above applications, some organophosphorus compounds have important functions as plant growth regulators and crop improvers (12.120). 

There is an evolving concern about the use of some particular organophosphates such as tricresyl phosphate, tri-n-butyl phosphate, and triphenyl phosphate [94,108-110]. Animal studies have shown that these phosphate esters can cause allergies, learning problems, and deterioration in sperm production and can influence the white and red blood cell counts of humans [109]. In a recent publication [110], levels of flame retardants in indoor air at electronics scrap recycling plant and other work environments were considered 15 brominated FRs and 9 organophosphorus compounds were analyzed. Although the measured concentrations found in all... 

Wang, X., Wu, N., Guo, J., et al., 2008. Phytodegradation of organophosphorus compounds by transgenic plants expressing a bacterial organophosphorus hydrolase. Biochem. Biophys. Res. Commun. 365, 453-458. 

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