Agricultural chemistry Herbicides Pesticides

A healthy garden represents a chemical laboratory in which a host of chemical processes are occurring in synchrony with our natural world. When the gardener has chosen adapted crop varieties, and has managed both soil and crops wisely, these chemical processes unfold in such a way that the garden harvests the sun s energy efficiently, and converts a portion into useful products, see also Agricultural Chemistry Herbicides Insecticides Pesticides. 

Provides access to detailed information on all categories of pesticides including herbicides, fungicides, insecticides, and rodenticides. Included is information on pesticide toxicity, health effects, residual data, efficacy, and other information. NPIC is a cooperative effort of the U.S. EPA and the Oregon State University Department of Agricultural Chemistry. NPIC is staffed from 6 30 a.m to 4 30 p.m. Pacific Standard Time. 

See Fertilizers Fungicides, agricultural Herbicides Insect control technology Soil chemistry of pesticides. 

The first section of this book describes the application of LC/MS to the analysis of agricultural chemicals and their metabolites. Using LC/MS for residue analysis in agricultural chemistry has become routine in many laboratories. Many pesticides, such as the chlorophenoxy acid and sulfonyl urea herbicides or organophosphorus and methyl carbamate insecticides, are too polar or thermally labile for analysis via GC. The use of LC/MS for the identification of polar pesticide metabolites and conjugates, an area traditionally dominated by radiolabeled compounds, stands out as a particularly dramatic demonstration of the power of this technique. 

Some of the effects of biotechnology on agricultural chemistry will be in direct competition with or in opposition to the use of chemicals, such as the development of pest resistant crops taking the place of present pesticides. Other applications will enhance or allow new uses for agricultural chemicals, such as (1) the transfer of herbicide resistance into otherwise... 

The field of organic chemistry has seen the most extensive use of polymeric materials as aids in effecting chemical transformation and product isolations. Polymers have been used in other, related areas of chemistry. Applications have been made in analytical chemistry (pH indicators and electrode modifiers), pharmaceutical and agricultural chemistry (controlled-release drugs, pesticides, herbicides, and fertilizers), and biochemistry (enzyme immobilization and affinity chromatography). Applications of polymers to solid-phase enzymo- and radioim-mune assays (Landon, 1977 Chard, 1978) will not be discussed since they are mainly analytical in scope. 

OPs are chemicals used in agriculture as acaricides, herbicides, and insecticides (Appendix 5-A-l). Because of their toxicity, several of these chemicals are being phased out from use parathion (ethyl) is an example. Many have been now classified by the United States Environmental Protection Agency (USEPA) as a restricted use pesticide (RUP) or a general use pesticide (GUP). Pesticide chemistry has taken a turn for the synthesis, manufacture, and use of still safer compounds. A list of OPs considered for banning has been identified by the USEPA (Table 5-3). The following pages will briefly discuss the uses and toxicity of different OPs. 

Provides chemical, physical, analytical, use, and toxicity data for nearly 1200 pesticides, herbicides, and other agricultural chemicals. Contains The Agrochemicals Handbook from the Royal Society of Chemistry. Environmental fate/transport, resistance information, and lists of manufacturers are also included. A companion tool from the Royal Society of Chemistry is the 3rd edition of the World Directory of Pesticide Control Organizations (ISBN 0-85404437X), which gives sources of contacts in over 160 organizations worldwide involved in the control of pesticides. 

Development of microbial and enzymatic systems for production of natural product chemistry for agriculture, including pesticides, secondary metabolites (e.g. bialaphos, with herbicidal activity), optical isomers, specialty chemicals, etc. 

Many chemicals are applied to soil and crops to control insects, fungi, and weeds. The potential toxi-cities of these substances to humans, wildlife, and beneficial plants is of course a concern. A comprehensive coverage of the toxicological chemistry of agricultural pesticides is beyond the scope of this chapter. However, three important herbicides, 2,4-dichlorophenoxyacetic acid (2,4-D), atrazine, and glyphosate, are mentioned here their structural formulas are shown in Figure 10.4. Herbicides are mentioned because they are so widely used in agriculture and are spread over wide areas. 

Nucleic acids, such as uracil, thyamine, adenine, and L-proline and l-phenyl-2-aminopropane, have been treated with methacryloyl chloride to prepare monomers. These modified methacrylamides may be copolymerized with MA to provide novel, potential drug carrier resins. This type of chemistry should also be exploitable to prepare water-soluble food dyes " and artificial sweeteners as well as deliver herbicides and pesticides in the agricultural industry. 

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