協力劑對抗百滅寧埃及斑蚊(苓雅品系)之效應

Abstract

合成除蟲菊殺蟲劑除了對昆蟲具有高度致死能力外還具有對哺乳動物低毒性的特性，在過去20年被廣泛用來作為居家環境及農業方面主要噴灑的藥劑種類，於1990年在高雄縣苓雅區採集的苓雅品系 (LYPL)，以百滅寧對每一代幼蟲篩藥至第35代，另以百滅寧添加協力劑piperonyl butoxide (PBO,細胞色素 P450抑制劑)自LYPL第30-4代對每一代幼蟲篩藥至第5代（LYPPL），以百滅寧自LYPL第30-4代對每一代成蟲篩藥至第5代（LYPA），以百滅寧添加協力劑PBO自LYPL第30-4代對每一代成蟲篩藥至第5代（LYPPA），LYPL、LYPPL、LYPA及LYPPA品系在幼蟲階段對百滅寧抗性比分別為322.27、148.18、182.73及296.82，在成蟲階段分別為46.57、40.51、98.08及40.30，在協力效果測試實驗中使用協力劑PBO、s,s,s-tributyl phosphorotrithioate (DEF, 酯抑制劑)、diethyl maleate (DEM, glutathione S-transferase抑制劑)及triphenyl phosphate (TPP, 酯 抑制劑)，發現在幼蟲階段僅有PBO及DEF具協力效果，在成蟲階段四種協力劑皆具協力效果，且LYPL、LYPPL、LYPA及LYPPA品系在幼蟲及成蟲階段對賽滅寧、酚丁滅寧及異治滅寧皆具中度到高度交互抗性，在幼蟲時期僅在LYPL發現抗性與細胞色素P450含量的提高有關，在成蟲階段則是LYPL及LYPPA的抗性與細胞色素P450活性的提高有關、LYPA的抗性與細胞色素P450含量及活性的提高有關，除此之外，抗性應還與其他抗性機制有關，如酯 、GST、作用目標的不敏感或穿透抗性。

Aedes aegypti is the vector of dengue fever, and dengue hemorrhagic fever in many tropical countries, including the southern areas of Taiwan. LYPL strain was collected from Lingya in Kaohsiung in 1990 and was selected with permethrin at larval stage for 35 generations. Three sub-strains;LYPPL, LYPA, and LYPPA were established by laboratory selection from LYPL strain. LYPPL strain was selected with a mixture of permethrin and piperonyl butoxide (PBO, a cytochrome P450 monooxygenase inhibitor) at larval stage for 5 generations. LYPA strain was selected with permethrin at adult stage for 5 generations. LYPPA strain was selected with a mixture of permethrin and PBO at adult stage for 5 generations. The resistance ratio of the four strains (LYPL, LYPPL, LYPA, and LYPPA) to permethrin at larval stage was 322.27, 148.18, 182.73, and 296.82, respectively. The resistance ratio at adult stage was 46.57, 40.51, 98.08, and 40.30, respectively. In the synergistic effect test, PBO, s,s,s-tributyl phosphorotrithioate (DEF, an esterase inhibitor), diethyl maleate (DEM, a glutathione S-transferase inhibitor), and triphenyl phosphate (TPP, an esterase inhibitor) were used and only PBO and DEF had effect on increasing permethrin toxicity at larval stage, and PBO, TPP, DEM, DEF were all had effect on increasing permethrin toxicity at adult stage. All the four strains had moderate to high level of cross-resistance to cypermethrin, phenothrin, and tetramethrin at larval and adult stage. In the cytochrome P450 monooxygenases and b5 content analysis, at larval stage the resistance was only associated with the higher content of cytochrome P450 of LYPL strain. At adult stage the resistance was associated with the higher activity of cytochrome P450 of LYPL strain and LYPPA sub-strain. And the resistance was associate with higher content and activity of cytochrome P450 of LYPA sub-strain. In addition to cytochrome P450, there should be other resistant mechanisms involved with resistance, such as esterase, glutathione-S-transferase, target site insensitivity and penetration resistance.