Abstract
In order to know the contact toxicity of several insecticides against an unusual poisonous beetle, Paederus fuscipes Curtis, a seris of tests was carried out under laboratry conditions. Overwintered adult insects collected from Koga, Ibaraki Prefecture, were used. Five emulsion of insecticides, γ-BHC (lindane), DDT, chlordane, diazinon and DDVP were tested through residue contact method using impregnated filter papers in various concentrations, and LC_<-50> values were assessed from the obtained results. It was confirmed that lindane is most excellent in the LC_<-50> value, and DDT comes next; but its concentration-mortality regression line shows a gentleslope; the others are following sequence of descending oder in the LC_<-50> value : i. e. diazinon, chlordane, DDVP.
