辣椒素对西花蓟马雌成虫体内解毒酶活性的影响

Effects of capsaicin on detoxification enzyme activity in adult female Frankliniella occidentalis

【目的】为明确非挥发性次生物质辣椒素对西花蓟马Frankliniella occidentalis雌成虫体内解毒酶活性的影响。【方法】将菜豆叶片研碎离心后取上清液作为西花蓟马的液态饲料,将不同浓度的辣椒素添加到饲料中,饲养西花蓟马雌成虫48、72、96 h后,分别测定西花蓟马体内羧酸酯酶(Car E)、谷胱甘肽-S-转移酶(GSTs)、乙酰胆碱酯酶(AChE)和多功能氧化酶(MFO)的活性。【结果】低剂量辣椒素能诱导西花蓟马雌成虫体内GSTs、AChE和MFO活性明显升高,高剂量辣椒素抑制GSTs、AChE及MFO活性。不论在哪一种辣椒素浓度下,Car E活性一直受到抑制。辣椒素浓度和处理时间对GSTs及AChE活性无明显交互作用,但对Car E及MFO有明显的交互作用,处理时间越长,作用越显著。【结论】西花蓟马雌成虫体内解毒酶活性在次生物质辣椒素处理下发生了明显的变化,说明西花蓟马通过解毒酶适应次生物质对其的影响,但解毒酶的变化有剂量和时间效应。

[Objectives] To investigate the effects of the non-volatile, secondary substance capsaicin on detoxifieation enzymes in adult female Frankliniella occidentalis. [Methods] Adult female F. occidentalis were fed bean leaf juice to which different concentrations of capsaicin had been added. Detoxification of the enzymes carboxylesterase （CarE）, glutathione S-transferase （GSTs）, acetylcholine esterase （ACHE）, and mixed function oxidase （MFO）, were determined after F. occidentalis had fed for 48, 72 and 96 h. [Results] Exposure to lower concentrations of capsaicin was followed by a significant increase in GSTs, AChE and MFO activity, but exposure to higher concentrations was followed by a significant decrease in the activity of these enzymes. CarE activity was inhibited by all eapsaicin concentrations. No significant interaction between capsaicin concentration and treatment time was apparent for GSTs and ACHE, but was for CarE and MFO; the longer the treatment time, the more significant the effect. [Conclusion] The activities of detoxification enzymes in adult female F .occidentalis changed significantly under eapsaicin treatment, which indicates that F occidentalis are able use certain detoxification enzymes to detoxify capsaicin. The magnitude of changes in detoxification enzyme activity were affected by dose and the duration of exposure.