New methods for the detection of insecticide resistant Myzus persicae in the UK suction trap network

1 Myzus persicae is a highly polyphagous pest of U.K. agriculture. It presents particular control difficulties because it has developed resistance to several insecticide classes. 2 For almost 20 years, M. persicae collected in the U.K. suction trap network have been analysed for insecticide resistance and the data disseminated to growers via a resistance bulletin. These data are generated by the biochemical analysis of individuals for two major resistance phenotypes: (i) elevated carboxylesterase and (ii) modified acetylcholinesterase (MACE). 3 The development of new polymerase chain reaction (PCR)-based technologies using fluorescently labelled probes has allowed other resistance mechanisms, such as knockdown resistance to pyrethroids (kdr/super-kdr), to be detected and has greatly increased the speed and accuracy of resistance monitoring. Unfortunately, these newer PCR-based assays are incompatible with the older biochemical assays. 4 The present study describes the development and testing of new compatible methods for detecting elevated carboxylesterases and MACE for use on M. persicae caught in the field or suction traps. 5 These new tests have significant advantages over present methodologies by allowing individual aphids to be tested for three resistance mechanisms quickly and accurately on a single platform.