Factors affecting the design of traps for stored-product insects.

Abstract

The availability of pheromones for many species of stored-product insects and the need to eliminate or greatly reduce the levels of insect infestation and contamination has led to increased interest in the development of traps for detecting and monitoring these insects. Traps have been developed for aerial insects (mainly pyralid moths and anobiids), for crawling stages of Coleoptera (Trogoderma, Tribolium and Oryzaephilus spp.) and for insertion into bulk grain for a complex of grain-infesting Coleoptera. Traps for aerial insects are most commonly sticky traps and funnel traps, modified to function in environments which may be dusty and which are observed by the public. Many traps for crawling Coleoptera are of corrugated materials and are designed to cause insects seeking shelter to drop into devices or onto adhesive surfaces. Food-baited traps have also been used for crawling Coleoptera. Perforated probe traps for grain are pitfall drop traps which contain an internal collection device such as a funnel tube. Successful traps are refinements of simple devices which utilize basic behavior to trap insects. Traps, to be popular in the marketplace must be easy to use, maintain and assemble, be reliable, easily produced, and cost effective. The design of traps for stored-product insects, along with and their availability and use, has received new interest which has paralleled progress in the identifi cation and synthesis of pheromones and attractants for the major pest species. In addition, regulatory requirements for reduced or zero tolerance of insect infes tation, damage, and contamination, driven by public concern over the health aspects of pesticide use, have made early detection and control of insects essential. Traps for the early detection, monitoring and survey of such insects have proven valuable in the continuing effort to protect food and fiber from insect damage or loss. This review describes some of the basic designs of traps for stored-product insects, how they work, and how trapping environment and use patterns affect their design. In addition we will present examples of the origin and development of two trap types, and finally, discuss how more practical requirements, such as commercial production, and consumer acceptance, have influenced our perception of what makes a trap design successful. We will not discuss mechanized traps, which will be covered in another review. Attractance to traps (using pheromones and/or food attractants) will be the subject of other authors in this series. Stored-product insect traps fall into three broad categories based on deployment: 1) traps for aerial insects including sticky and funnel types; 2) surface-deployed traps for crawling insects, including harborage, sticky and pitfall types, and food Mention of a proprietary product does not constitute an endorsement or recommendation of its use by the USDA. 1 Stored-product Insects Research Unit, USDA, Agricultural Research Service, Department of En tomology, University of Wisconsin, Madison, Wisconsin 53706 USA. 2 Philip Morris USA, Research Center, P.O. Box 26583, Richmond, Virginia 23261 USA. Accepted for publication 15 July 1990. This content downloaded from 207.46.13.172 on Fri, 07 Oct 2016 05:57:24 UTC All use subject to http://about.jstor.org/terms VOLUME 63, NUMBER 4 467 or bait-bag traps; 3) traps used in grain, including sub-surface pitfall and perforated probe traps. These categories become less distinct as traps are used for different purposes and for species other than those for which they were originally designed. We also show that several different types are conceptually similar in the actual mechanism of entrapment. It would be equally logical to categorize traps as those which catch flying adults (such as Plodia interpunctella (Hubner) and Lasioderma serricorne (Fabricius), or those which catch crawling forms (such as Oryzaephilus surinamensis (L.), Tri bolium confusum Jacquelin duVal, and Trogoderma granarium Everts, etc.). These classes become less rigid as well, since under certain conditions insects (such as Trogoderma variabile Ballion) may either fly or, unable to fly due to environmental or biological restraints, crawl to non-aerial traps.