Insecticides research

Truhaut R, Gak JC, Graillot C. 1974. [Organochlorine insecticides Research work on their toxic action, its modalities and mechanisms. Part 1 Comparative study of the acute toxicity on the hamster and the rat.] Eur J Toxicol Environ Hyg 7 159-166. (French)... 

For Physiology or Medicine speech 1948 and biography. Nobel Lectures, Physiology or Medicine, 1942-1962. New York Elsevier, (1964) 147-176. Source for Muller s childhood youth early Geigy career insecticide research plan, ideal insecticide, and DDT discovery biologists skepticism and caution about insecticides in complex ecological systems. 

DETAILS - VX, like most other nerve gases, originated from insecticide research, which in this case, was done in Britain in the late 1950 s. Unlike Sarin, VX is a persistent agent - meaning it can stay on target... 

Herbicides, used to kill or damage a plant, are the most rapidly growing segment of pesticides. Prior to the 1930s, herbicides were non-specific and often very toxic to humans as well as other animals. In the 1930s, in parallel with the development of new insecticides, researchers discovered several chemicals that selectively killed plants. These chemicals are now widely used to increase food production and have been used in warfare. Herbicides come in a variety of chemical structures and mechanisms of action, so they will be discussed in only general terms. Interested readers are referred to the many web sites and extensive literature on herbicides (see below and the presentation). 

In this connection, Conway does point to one "tenable global threat" agrochemical discovery and manufacture is increasingly concentrated in a few companies, and should one or more decide to abandon insecticide research in favor of "more profitable pesticides" the threat to food production would be serious (22)-... 

The same could be said of fungicide research, which historically has been concentrated in even fewer companies than insecticide research. 

Potential for fir resistance. During the relatively short gap in time between discovery and commercialization of rDNA insecticides, researchers will hopefully have an opportunity to explore an important potential limitation to the use of Br-based insecticides-the development of resistance. In 1985, McGaughey reported evidence for the only documented case of Bt resistance in a field population of insects (291. The Indian meal moth, Plodia interpunctella, is a lepidopteran pest of stored grain that was successfully controlled with Bt variety kurstaki for several years. However, McGaughey s study showed that an observed decline in the efficacy of Bt was due to the development of resistance among treated Plodia populations. 

Casida, J.E. and Quistad, G.B. 1998. Golden age of insecticide research past, present, or future Annu. Rev. Entomol., 43,1-16. 

The problem of eliminating side-effects on nontarget organisms is most studied in insecticide research. This is partly because the recognition of specific biochemical and behavioural characteristics of insects has created a good theoretical basis for research, and partly because, of all pesticides, insecticides represent the greatest... 

These compounds themselves do not exhibit insecticidal action, but owing to their potent bioactivity, workers in insecticide research in the mid-1940s directed their attention to N-substituted carbamic acid esters. Pioneer work in this held is linked with the names of Metcalf and Gysin (Metcalf and March, 1950 Kolbezen et ai, 1954 Gysin, 1952). 

In 1981 when juvenoid research was started at Sumitomo Chemical, insecticide research was focused mainly on pyrethroids that act quickly on insects and have a wide insecticidal spectrum. However, the appearance of resistant insects owing... 

Caron aldehyde ester was of great help particularly for the casual preparation of many chrysanthemic acid analogues for insecticidal research. Instead of triphenyl phosphine the trisdimethylamino phosphine may be apphed preferentially [247]. The production of caronaldehyde 755 by the route outUned above is still essential for the production of deltamethrin. Alternatively to the Wittig reaction, the dichlorome-thylene moiety may be introduced by reaction of carbenoids or carbanions from haloforms with the hemiketal 158 of free cis-caronaldehyde, (reaction scheme 100) [248, 249] and subsequently completed by dehalogenation processes. 

The idea of Volums 4 and 5 of this series is a combination of a very condensed but broad review, handbook and textbook on most of the theoretical and practical aspects of pyrethroids of interest to chemists, biologists, pharmacologists, toxicologists and other people involved in insecticidal research, development, ecotoxicolo-gy, application, patenting and commercialization of pyrethroids, as seen from a point of view of an industrial chemist once actively involved in pyrethroid research. 

Much of the effort on viral insecticide research has been aimed at the development of adjuvants to improve efficacy. Although some effort has been directed at incorporation of adjuvants into the basic formulation, a majority of effort has been with spray tank adjuvants. Materials to overcome the potential efficacy limiting characteristics of the virus (e.g. stability and coverage) have been targets of research. 

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