亚致死浓度氰氟虫腙对小菜蛾三种解毒酶及P450 mRNA表达量的影响  

Effects of sublethal concentrations of metaflumizone on detoxifying enzyme activity, and expression of cytochrome P450 genes, in Plutella xylostella(L.)

作　　者：申君[1] 鲁艳辉[2] 张淑真[1] 游红[1] 李建洪[1] 

机构地区：[1]华中农业大学植物科学技术学院,武汉430070 [2]浙江省农业科学院植物保护与微生物研究所,杭州310021

出　　处：《应用昆虫学报》2016年第2期256-263,共8页Chinese Journal of Applied Entomology

基　　金：公益性农业行业专项(201103021)

摘　　要：【目的】为探讨亚致死浓度氰氟虫腙对小菜蛾Plutella xylostella（L.）3种解毒酶和细胞色素P450基因表达量的影响。【方法】采用叶片浸渍法,测定用氰氟虫腙LC10和LC25处理72 h后小菜蛾羧酸酯酶、谷胱甘肽S-转移酶和多功能氧化酶3种解毒酶的活性;应用实时荧光定量PCR（Real-time PCR）方法测定了其在24、48和72 h时对P450基因（Px CYP4、Px CYP6和Px CYP9家族）表达的影响。【结果】结果表明,氰氟虫腙LC10和LC25处理对羧酸酯酶活性影响不显著;对谷胱甘肽S-转移酶活性存在显著抑制作用（P〈0.05）;LC25处理后多功能氧化酶活性显著增加（P〈0.05）,为对照的1.39倍。同时,LC25氰氟虫腙处理组小菜蛾P450基因Px CYP4M19、Px CYP6BF1V2、Px CYP6CN1和Px CYP6CV2 m RNA的相对表达量分别为对照组的2.33-8.5倍、1.32-3.48倍、1.18-2.53倍、2.02-7.22倍。【结论】结果显示,氰氟虫腙可能通过诱导这4种P450基因m RNA的上调表达而增强了小菜蛾多功能氧化酶酶活性。[Objectives] To clarify the effects of sublethal concentrations of metafumizone, a novel sodium channel blocker insecticide, on the activities of detoxifying enzymes（carboxylesterase, glutathione S-transferase and function oxidase）, and the expression of cycochrome P450 genes, in Plutella xylostella（L.）. [Methods] The activities of the three detoxifying enzymes and the m RNA expression levels of three P450 gene families（Px CYP4, Px CYP6 and Px CYP9） in P. xylostella were measured in 3rd instar larvae treated with sublethal doses of metafumizone（LC10 and LC25） via the leaf-dip bioassay method. [Results] There was no significant difference in carboxylesterase（Car E） activity compared with the control, but glutathione S-transferase activity（GSTs） was distinctly inhibited by sublethal concentrations of metaflumizone（P〈0.05）. O-demethylation activities of mixed-function oxidases（MFOs） were significantly increased by sublethal concentrations of metaflumizone. When P. xylostella were treated with metaflumizone at LC25 for 72 h, MFOs activity significantly increased（P〈0.05） to 1.39-fold that of the control. The relative expression levels of Px CYP4M19, Px CYP6BF1V2, Px CYP6CN1 and Px CYP6CV2 after exposure to metaflumizone（LC25） were, respectively, 2.33-8.5-fold, 1.32-3.48-fold, 1.18-2.53-fold, and 2.02-7.22-fold, those of the control. [Conclusion] The results suggest that metaflumizone up-regulates the expression of four P450 genes and enhances the activity MFOs of in P. xylostella.

关 键 词：小菜蛾 氰氟虫腙 解毒酶 细胞色素P450基因 

分 类 号：S433.4[农业科学—农业昆虫与害虫防治]