Abstract: A major challenge in pest management is insecticide resistance. To effectively prevent and manage resistance, it is essential to understand the biochemical and physiological changes induced by insecticides. Some molecular mechanisms that are responsible for insecticide resistance were well known whereas others are to be discovered. So the comparative proteomic approach was employed to investigate the proteomic differences between the deltamethrin-sensitive strain (DS) and the deltamethrin-resistant strain (DR) of the diamondback moth (Plutella xylostella L.). In this study, about 300 differentially expressed protein spots were detected on each SDS-PAGE gel, among which 23 proteins had a 2.5-fold expression difference between the two strains. Eight proteins were successfully identified by MALDI-TOF-MS, including chemosensory protein CSP2, Cu/Zn superoxide dismutase (SOD1), peroxiredoxinlike protein, etc. Expression of the five proteins at the mRNA level was analyzed by real-time quantitative PCR, and the results showed that the mRNA expression level did not fully reflect the protein expression level. Western blotting validated the proteomic result of SOD1. This study provides strong evidence that deltamethrin can induce the proteomic change in adult diamondback moth, and is helpful to understanding the resistance development and selecting the action targets of deltamethrin.

Key words: Plutella xylostella, deltamethrin, proteomics, selection pressure, insecticide resistance