The effects of local selection versus dispersal on insecticide resistance patterns: longitudinal evidence from diamondback moth (Plutella xylostella (Lepidoptera : Plutellidae)) in Australia evolving resistance to pyrethroids
NM Endersby, PM Ridland, AA Hoffmann
Bulletin of Entomological Research | CAMBRIDGE UNIV PRESS | Published : 2008
When strong directional selection acts on a trait, the spatial distribution of phenotypes may reflect effects of selection, as well as the spread of favoured genotypes by gene flow. Here we investigate the relative impact of these factors by assessing resistance to synthetic pyrethroids in a 12-year study of diamondback moth, Plutella xylostella, from southern Australia. We estimated resistance levels in populations from brassicaceous weeds, canola, forage crops and vegetables. Differences in resistance among local populations sampled repeatedly were stable over several years. Levels were lowest in samples from weeds and highest in vegetables. Resistance in canola samples increased over time..View full abstract
Thanks to Jingye Zhang for technical assistance. Thanks to the Department of Agriculture, Western Australia; SARDI; Department of Primary Industries, Water and Environment, Tasmania; Agriculture NSW; Department of Primary Industries Queensland and others for collecting populations of P. xylostella from canola and vegetable crops. We are grateful to Mike Keller for supplying the Waite susceptible population of P. xylostella. Thanks to Steve McKechnie for cornments on an earlier version of the manuscript. We also thank the agrochemical companies who were involved in Supporting a national insecticide resistance testing program for P. xylostella: Aventis CropScience, BASF Australia Ltd, CropCare Australasia, Dow AgroSciences Australia Ltd, DuPont (Australia) Ltd, NuFarm Ltd, Sumitomo Chemical, Syngenta Crop Protection Pty Limited and AIRAC (AVCARE's Insecticide Resistance Action Committee). The study was funded by Horticulture Australia Limited, an Australian Research Council Strategic Partnership with Industry Research & Training Grant, Department of Primary Industries Victoria (Industry Partner), the Grains Research and Development Corporation and the Australian Research Council via their Special Research Centre program.