Author
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Greenstone, Matthew |
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Submitted to: Journal of Arachnology
Publication Type: Peer Reviewed Journal Publication Acceptance Date: 10/17/1998 Publication Date: N/A Citation: N/A Interpretive Summary: The use of insect natural enemies is a well-accepted component of integrated pest management (IPM) programs for insect pests. However, with the exception of rice in South and Southeast Asia, one major group of natural enemies, the spiders, has been neglected. This review as undertaken in order to determine the most efficient approaches to studying spiders' impact on insect pests, so as to hasten their incorporation into insect pest management programs. It was shown that direct observation of spider predation events in the field, analysis of spider gut contents using antibody-based assays, and field experimental manipulations are the most effective means to obtain the necessary data, and that published experiments have already demonstrated the effectiveness of spiders in reducing insect pest populations. Technical Abstract: Predation is of great ecological, evolutionary, and behavioral interest. For our present purposes the primary reason for studying it is to determine the role of spiders in suppressing pest populations. Research approaches have included laboratory studies of preference, feeding rate, and fitness; direct observation of predation events or accumulations of prey carcasses; gut analysis; and field experiments. Laboratory studies provide some uniquely useful kinds of information but cannot give reliable indications of the "biological control potential" of spiders against a given pest. Direct observation can be powerful; it has provided the best data on dietary range and predation rates in the field. Gut analytical methods include the use of radionuclides, electrophoresis, chromatography and serology. Serological techniques are preferred: antibodies can be made specific down to the level of prey stage or instar, and assays are simple, sensitive, and reliable. They can determine the relative importance of different predator species, and may be the most efficient methods to document predation on eggs. Problems in quantitation remain. Field experiments have demonstrated unequivocally that spiders can effectively reduce pest populations and the crop damage they cause. |
