Insecticide resistance in populations of the diamondback moth, Plutella xylostella (L.) (Lepidoptera: Plutellidae), from the state of Pernambuco, Brazil

摘要: The diamondback moth Plutella xylostella (L.) has a great economic importance in Brassicaceae crops many parts of the world. Recurrent infestations this pest growing areas Pernambuco state, Brazil, have led farmers to frequently spray their with insecticides. However, control failures by several insecticides been alleged farmers. objective study was check whether resistance could explain these P. xylostella. Populations from were collected between January and April 2009. ratios populations compared among five different active ingredients: abamectin, methomyl, lufenuron, indoxacarb, diafenthiuron leaf dipping bioassays using foliar discs kale leaves. Mortality data submitted probit analysis. showed variable response significant one or more population Bezerros County exhibited highest indoxacarb (25.3 times), abamectin (61.7 lufenuron (705.2 when reference population. Bonito Jupi Counties 33.0 12.0 times resistant respectively, Resistance methomyl least common, but not less important, at four populations. These results indicated that associated some evaluated insecticides, reinforcing need for management state Pernambuco.