Toxicity of twenty-nine insecticides to Folsomia candida: laboratory studies.

Abstract

The suitability of Folsomial candida Willem for screening 29 insecticides was assessed y direct contact action in a Potter spray tower and in a Plainfield sand. Similar assays were done with 2 pre- and posttreatment temperatures, 13±1°C and 24±1°C. Methomyl, dieldrin, heptachlor, and duPont 1642 (methyl N-(carbamoyloxy) thioacetimidate), were more toxic by direct action when the insects were held at 13°C than at 24°C after treatment at 21±2°C, No insecticides appeared to be more toxic by direct contact at 24°C than at 13°C. In soil, 8 insecticides (Dyfonate® ( O -ethyl S -phenyl ethylphosphollodithioate), N-2596 ( S -( p -chlorophenyl) O -ethyl ethylphosphonodithioate), disulfoton, carbofuran, chlorpyrifos, endrin, diazinon, and chlorfenvinphos (2-chloro-1-(2,4-dichlorophenyl) vinyl diethyl phosphate) were more toxic at 24°C than at 13°C. The toxicity of methomyl and heptachlor in soil was negatively correlated with temperature. The species fulfilled the basic requirements of an organism for bioassay.