Boll weevil research

Center for Alluvial Plains Studies, Delta State University, Cleveland, MS 38733 Boll Weevil Research Laboratory, Midsouth Area, U.S. Department of Agriculture, Agricultural Research Service, Mississippi State, MS 39762-5367... 

Paul A. Hedin, EDITOR Boll Weevil Research Laboratory... 

Boll Weevil Research Laboratory Mississippi State, MS 39762... 

One aspect of the current work on chemical control of insects centers on the use of sex pheromones as lures. Recently, chemists at the U.S. Department of Agriculture s Boll Weevil Research Laboratory isolated and synthesized components of the sex attractant of the male boll weevil, a pest responsible for a prodigious loss of cotton crop in the United States. A stereoselective synthesis of the active pheromone was later carried out at the Zoecon Corporation, and is outlined below. A key feature of this synthesis is the photochemical cycloaddition of ethylene to 3-methylcyclohex-2-enone, followed by oxidative disconnection of the resulting c/s-fused bicycio[4.2.0] octane (A) thereby generating the cis disposed side-chains. 

Since so few curculionid pheromones have been identified, we do not yet know what role chirality will play or the importance of blends in mediating behavior within this family. Obviously, since the boll weevil response to individual components or pairs of components is almost nil, the blend is important. However, the boll weevil is essentially an introduced pest, having migrated into the U. S. in about the second decade of this century from Central America. Thus interactions related to chemical communications between the boll weevil and other closely related species have not been studied. Much more research is needed in this area before we will begin to understand how this insect and related species interact in the ecosystem. 

Resistance hits hard in agriculture. For example, the boll weevil, which showed a pronounced resistance to toxaphene and other chlorinated hydrocarbons in 1955, affects 80% of the total cotton acreage and more than 95% of all cotton producers in the United States. As resistance builds up it affects not only the grower, particularly of cotton, but the pesticide chemical industry. Costs of development of a pesticide range from 500,000 to perhaps something over 3,000,000. The chemical industries may very well question the development of a new chemical that may have a relatively short market life expectancy because of resistance. Here the opponents of pesticides can score with ample justification. What do the proponents have to say First of all, substitute insecticides must be tested to the utmost this has yielded some very definite successes. Then all other means must be explored. Basic research, however, is sorely needed. What causes resistance We are learning something about it and there are... 

We synthesized 173 by titanium(IV) chloride-catalysed imine formation between A and B.18 The product 173 showed no definite antifeedant activity against adult cotton boll weevils as tested by researchers at Sumitomo Chemical Co., Ltd. At the concentration of 500 ppm, it seemed even to stimulate feeding.18 The structure 173 is too unusual to be a real natural product. 

O. El-Lissy and W. Grefenstette, Boll Weevil Eradication in the U.S. 2001, in Proc. 2002 Beltwide Cotton Conf. (Cotton Insect Research Control Conf.), National Cotton Council, Memphis, Tenn., 2002 [CD-ROM]. 

The Chemical Warfare Service, in addition to conducting research and development on various aspects of chemical warfare, co-operated with other branches of the Army, with the U.S. Public Health Service, and with the Navy on projects of a quasi-public-health nature. In 1920 the service was directed to co-operate with the Medical Department and the Quartermaster Corps on the extermination of rodents and vermin. Later the CWS worked on methods of exterminating the boll weevil and on improved methods for fumigating ships. ... 

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