Efficacy of several insecticides to red-back widow spiders, Latrodectus hasseltii, collected in Osaka and Mie Prefectures, Japan

Abstract

Lethal and knockdown effects of several insecticides to red-back widow spiders, Latrodectus hasseltii, were evaluated. Spiders were collected three times in Osaka and Mie Prefectures, Japan, in 1995 and 1996. In the continuous contact method on glass pot and the topical application method, permethrin and phenothrin were most effective among the tested insecticides. Knockdown and lethal effects by spraying with commercial insecticide aerosols, containing pyrethroids, were sufficient in the case of direct spraying without the web, but the effects decreased in the case of spraying through the web.