Resistance to insect penetration of food pouches made of untreated polyester or permethrin-treated polypropylene film

Untreated polyster or permethrin-treated polypropylene food pouches were exposed to large populations of Tribolium castaneum (Herbst), Rhyzopertha dominica (F.), Lasioderma serricorne (F.), and Cadra cautella (Walker). Also included were control pouches made of untreated polypropylene film, and standard pouches made of polyethylene film 254 mu m thick. L. serricorne did not penetrate polyester film and penetrated permethrin-treated film and polyethylene at similar low rates. R. dominica penetrated almost all polyethylene pouches, all untreated polypropylene pouches, about half the polyester pouches, and ca. 19% of the permethrin-treated pouches. In general, the order of descending resistance to penetration by the four species was permethrin-treated film, polyester film, polyethylene film, and polypropylene film.