Stored Product And Structural Pests

Harvesting, storage, and packaging provide no guarantee of safety to food and useful items from the ravages of insects and mites. Many species adapted for feeding on seeds, cellulose, and animal tissues and hair are naturally attracted to items composed of these materials which are brought in from the field (Baur 1984). The majority of these pests (Cotton 1960) are now cosmopolitan as a result of their association with commercial products that are distributed throughout the world through trade. They survive well in warehouses, storerooms, the holds of ships, and in the marketplace, where their presence and feeding degrades or destroys cereals and grains, paper, wood, fur and hides, fabrics, and other organic materials. Stored product pests are not well investigated as a group in Latin America, with some exceptions (Granovsky 1976, Passoa 1983).

Damage to grain in elevators and silos constitutes the largest losses to stored products. Grain, meal, and flour are attacked by a variety of beetles (Hinton 1945), moths (Corbet and Tams 1943), and mites (Flecht-mann 1983). Beetle adults and larvae eat the kernels of rice, wheat, corn, and so on.

These include the rice and granary weevils (Sitophilus) and the various grain beetles (Tribolium and Tenebrio, Oryzaephilus, etc.). Fortunately, the dreaded khapra beetle (Trogoderma granarium), which prefers dried vegetable products but also attacks animal products, is not now known to exist anywhere in Latin America. Its potential introduction is a constant menace, however. A number of grain beetles serve as intermediate hosts for human tapeworms (Hymeno-lepis), thus assuming medical importance (Caceres and Guillen de Tantalean 1972).

The larvae of flour and meal moths eat milled seeds and contaminate provisions with their webbing and feces. The principal of fenders in this category are the Mediterranean flour moths (Ephestia, Anagasta), Angoumois grain moth (Sitotroga cerealella), and Indian meal moth (Plodia interpunc-tella). A considerable variety of mites (Caceres etal. 1989, Flechtmann 1983:145-160) infest stored grains, some of which actually feed on fungi growing there and not on the produce itself . Also, several types bite and cause dermatitis ("itch mites") in granary workers and bakers.

In Latin America, termites are the chief destroyers of finished wood products. Many species are important, especially Coptotermes, which feeds not only on houses and lumber but on forest trees as well. Other major wood pests include pow-derpost beetles (especially Lyctus). Stored paper, including books, frequently is damaged not only by these insects but by silver-fish, psocids, ants, and bostrichid beetles.

The leather industry is plagued by hide beetles (Derrnestes) that riddle cowhides during the tanning process and storage. The cigarette beetle (Lasioderma serricorne) and drugstore beetle (Stegobium paniceum) lay waste to dried tobacco. They also destroy all manner of dry animal and plant products in the home and shops (stored nuts, cereals, spices, candy, etc.).

Wool garments and furs are subject to destruction by Webbing clothes moths

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