Laboratory‐Based, Insecticide Efficacy Studies on Field‐Collected Frankliniella occidentalis (Pergande) (Thysanoptera: Thripidae) and Implications for its Management in Australia

Two field collected strains of western flower thrips, Frankliniella occidentalis, were tested against proprietary and experimental formulations of insecticide. Thrips were tested using a novel method whereby thrips were confined in testing units throughout all stages of the bioassay procedure. The bioassay technique proved to be quick and robust. Of the chemicals tested, the two non‐registered compounds chlorfenopyr and fipronil were most active against field‐collected F. occidentalis. The field‐collected strains were tolerant to a range of organophosphate, carbamate and pyrethroid chemicals. Comparisons of dose‐response curves with established field‐use‐rates indicate that only methiocarb and methamidophos are likely to be completely effective in the field. The theoretical implications of the data for management of F. occidentalis in Australia is discussed.