Spinosad effectively controls Colorado potato beetle,Leptinotarsa decemlineata(Coleoptera: Chrysomelidae) in organic potato

Commercial formulations of spinosad applied at three concentrations of 0.2, 0.1, and 0.05%, and three temperatures of 15, 20, and 25 8C, were tested against Colorado potato beetle, Leptinotarsa decemlineata (Say) under laboratory conditions.Spinosad was toxic by both contact and ingestion.Investigations of interactions between temperatures and doses of spinosad showed that a temperature of 15 8C and a concentration of 0.2% caused a statistically higher mortality of adult insects than did other temperatures and concentrations.This was confirmed in another experiment involving control of the overwintered beetles, in which the mortality of larvae was statistically higher at 0.2% but the temperature had no influence on the results.The Colorado potato beetle was found to be highly susceptible to spinosad and therefore could be effectively controlled in organic potato fields.