Effects of Nicotine, a Plant Secondary Metabolite, on Protective Enzyme and Detoxification Enzyme of Frankliniella occidentalis

摘要

[Objective] The paper was to explore the effects of plant secondary metabolite on protective enzymes and detoxification enzymes of quarantine pest Frankliniella occidentalis.[Method] F.occidentalis were continuously exposed to artificial diets containing nicotine from the second to fifth instars for five generations, and the effects of nicotine on protective enzymes and detoxification enzymes of larvae were determined.[Result] The activities of carboxylate esterase (CarE) and glutathione-S-transferase (GST) in midgut of the fifth instar larvae were significantly increased, and reached the maximum at the third generation (1.86 times and 1.59 times, respectively). Nicotine inhibited the activities of superoxide dismutase (SOD) and catalase (CAT). With the increase of feeding generations, the inhibitory effect of nicotine weakened. Nicotine significantly increased the activities of peroxidase (POD).[Conclusion] F. occidentalis will gradually adapt to the harm of plant toxins by starting its own detoxification enzyme system and regulating protective enzyme system after feeding on plant secondary substance nicotine.