Plant protection chemical pesticides

The recent advances in identifying and utilizing allelochemlcs Involved in host-plant resistance has drawn the attention of the pesticide Industry. A potential problem that may not be recognized, is the effect on insects if analogs of plant protective chemicals are sprayed on agricultural crops. Insects treated with such analogs, could rapidly become tolerant not only to the analog, but also to the natural allelochemlc. 

Pesticides are applied to control pests and plant diseases. Pesticides used in agriculture to protect living plants and freshly harvested crops are called plant protection chemicals. When pesticides are used to protect stored food, processed goods, public hygiene, and dead objects, they are called biocides. Pesticides are divided into subgroups named after the pest they fight (Table 11.1). Examples discussed in this book are... 

Plant species Number of farms Total chemical plant protection measures Fungicides Pesticides Herbicides Insecticides Growth regulators... 

The Directive covers 23 different product types specified in Annex V of the Directive. These include disinfectants used in different areas, chemicals used for preservation of products and materials, nonagricultural pesticides, and antifouhng products used on hulls of vessels. The Directive will not apply to certain product types already covered by other community legislation, such as plant protection products (PPPs) (Section 2.4.1.7.2), medicines, and cosmetics. 

Pesticides are vital agricultural tools that protect food and fiber plants from damage by insects, weeds, diseases, nematodes, and rodents. U.S. agriculture spends about 8 billion annually on pesticides, representing about 70% of domestic pesticide sales. The dependence of agriculture on chemical pesticides developed over the last 60 years as the agricultural sector shifted from labor-intensive production methods to more capital- and chemical-intensive methods. 

Wiley recognized the opportunity for the introduction of a series of books within the theme Agrochemicals and Plant Protection with a wide scope that includes chemistry, biology and biotechnology in the broadest sense. This series is effectively a replacement for the successful Progress in Pesticide Biochemistry and Toxicology , edited by Hutson and Roberts, which has run to nine volumes. In addition, it complements the international journals Pesticide Science and Journal of the Science of Food and Agriculture, published by Wiley on behalf of the Society of Chemical Industry. 

The U.S. Environmental Protection Agency reported extensively on its R and D programmes for detoxifying hazardous waste, e.g., from deserted refineries, chemical plants, herbicide and pesticide factories and storage facilities, etc. An interesting contribution was made by Col. D. Naugle, the Deputy Director of Environmental Policy, U.S. Department of Defense, which inevitably has to handle immense quantities of hazardous waste. The... 

Controlled release of agrochemicals (e.g., by hydrolysis of a polymeric ester) can offer the advantages of constant level, smaller dose, reduced evaporation loss, lower toxicity, longer life, decreased environmental pollution, and reduced effect on nontarget species by wind or runoff.20 Systemic pesticides are preferred. This ensures protection of the growing tip of the plant. For weed killers, this means that it is not necessary to hit every leaf of the plant with the herbicide. Pesticides are often applied on a spray schedule according to the calendar as a prophylactic measure. Chemical pesticides are used 98% of the time. 

An attempt has been made to give an overview of all chemical aspects of plant protection, with the exception of analytical chemistry. We are fully aware that the designation chemistry of pesticides does not cover an unequivocally defined, uniform branch of science, because the fundamental sciences on which it is built, particularly organic chemistry and biochemistry, have maintained their independence and their original scope also within the frame of this special field. The chemistry of pesticides integrates these fundamental sciences only functionally, and not with respect to their methods. Our book attempts to achieve this functional unity. In the discussion of individual compounds and types of compound our aim has been to cover preparative and organic chemical and biochemical aspects, metabolism, activity-structure relationships, fields of application, and environmental and toxicological problems. 

In 1952 chemists at the Plant Protection Laboratories of the giant Imperial Chemical Industries were attempting to develop a new pesticide. One of the I Cl chemists, Dr Ranajit Ghosh, discovered a substance which appeared to be so toxic that not only would it destroy insects, but it might also kill humans. He sent a sample, together with the chemical formula, to Porton Down.22... 

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