内共生菌Cardinium对烟粉虱MED隐种耐药性的影响

【目的】次生内共生菌感染可影响烟粉虱Bemisia tabaci对杀虫剂的敏感性。本研究旨在揭示内共生菌Cardinium感染对烟粉虱B. tabaci MED隐种耐药性的影响。【方法】室内测定海南陵水与山东寿光烟粉虱MED隐种种群内遗传背景一致的Cardinium感染与未感染品系对不同浓度新烟碱类杀虫剂噻虫嗪和吡虫啉的耐药性。【结果】各浓度噻虫嗪和吡虫啉处理后，烟粉虱陵水种群感染Cardinium品系死亡率比未感染品系显著降低；100， 150, 175和200 mg/L噻虫嗪以及175和200 mg/L吡虫啉处理后，烟粉虱寿光种群感染Cardinium品系死亡率比未感染品系显著上升。相对于未感染品系，烟粉虱陵水种群感染Cardinium品系对噻虫嗪、吡虫啉的抗性倍数(RR)分别是1.355和1.847，烟粉虱寿光种群感染Cardinium品系的RR分别是0.790和0.847。【结论】内共生菌Cardinium感染能影响烟粉虱MED隐种对噻虫嗪和吡虫啉的耐药性，且这种影响在不同种群间存在差异。研究结果对于揭示烟粉虱MED隐种的种群适应性及扩张机制具有重要参考价值。

Influences of endosymbiontCardiniumon the insecticide tolerance ofBemisia tabaciMED (Hemiptera: Aleyrodidae)

【Aim】 Secondary endosymbionts may affect the susceptibility of Bemisia tabaci to insecticides. This study aims to reveal the influence of endosymbiont Cardinium infection on the insecticide tolerance of B. tabaci MED. 【Methods】 The tolerance of Cardinium-infected and uninfected lines with identical genetic background of two populations of B. tabaci MED (Lingshui population from Lingshui, Hainan Province, South China, and Shouguang population from Shouguang, Shandong Province, North China) to different concentrations of two neonicotinoid insecticides (thiamethoxam and imidacloprid) was assayed in the laboratory. 【Results】 After treatment with various concentrations of thiamethoxam and imidacloprid, respectively, the mortalities of the Cardinium-infected line of Lingshui population were significantly lower than those of the uninfected line. After exposure to 100, 150, 175 and 200 mg/L thiamethoxam and 175 and 200 mg/L imidacloprid, respectively, the mortalities of the Cardinium-infected line of Shouguang population were significantly higher than those of the uninfected line. Compared with the uninfected line, the resistance ratios of the Cardinium-infected line of Lingshui population under the pressure of thiamethoxam and imidacloprid were 1.355 and 1.847, respectively, while those of Cardinium-infected line of Shouguang population were 0.790 and 0.847, respectively. 【Conclusion】 Endosymbiont Cardinium infection can significantly influence the tolerance of B. tabaci MED to thiamethoxam and imidacloprid, and the influence varies among its different populations. The results provide valuable references for revealing the population adaptability and expansion mechanism of B. tabaci MED.