Insecticide Resistance Study in Plutella xylostella L. Ⅸ. The Selective Metabolism of Insecticides

小菜蛾抗藥性之研究　Ⅸ.幼蟲體內對不同殺蟲劑之選擇代謝

鄭允(E. Y. Cheng) ； 林端方(D. F. Lin) ； 蔡湯瓊(T. C. Tsai) ； 高靜華(C. H. Kao)

《中華農業研究》 37卷3期 (1988/09) Pp. 328-339

https://doi.org/10.29951/JARC.198809.0012

摘要

經由抗性與感性品系小菜蛾(Plutelta xylostella L.)雜交之子代(F1)對殺蟲劑的抗性明顯下降，而以對芬化利之抗性下降幅度最大，其次爲加保扶，拜裕松及美文松。降幅不同之原因，可能係其抗性遺傳控制機制來源不同所致，但有一反常之現象即對培丹之抗性反而上昇。由於F1子代酯酶之種類及活性均較原抗性及感性品系多且高，可導致酯酶水解培丹的能力提高，促進培丹之代謝分解，因而提高了小菜蛾之耐力。此外，感性小菜蛾天生俱有之多功能氧化酶，可代謝分解diflubenzuron，triflumuron及ethofenprox，却不能代謝teflubenzuron，chlorfluazuron及芬化利。經以協力劑pb抑制多功能氧化酶之作用後發現，diflubenzuron及triflumuron兩者對小菜蛾致死濃度趨於一致，但仍較telfubenzuron及chlorfluazuron爲差，因此此一毒性之差別不是由於代謝分解所造成的，可能源於前二者之分子結構不適合與小菜蛾體內作用點之結合有關。經由協力劑pb之作用，ethofenprox之功效反而與芬化利相當或更佳，由此可知，係由於ethofenprox容易被代謝分解，以致其致死能力不如芬化利，而與其分子結構無關，即ethofenprox結構中之醚鍵並未對其與小菜蛾體內之毒理作用點之親和性造成差別。對於幾乎全以酯鍵爲結構之合成除蟲菊精類而言，上述結果在毒理上爲一突破性之發現，即對除蟲菊分子之毒性而言，酯鍵的存在並非一定是必要的。

並列摘要

The genetic dilution of resistance and the selective metabolism of insecticides were investigated in the diamondback moth (DBM), Plutella xylostella L. The resistance to mevinphos, diethquinalphion, carbofuran and fenvalerate reduced differently which indicated that the resistance mechanisms for these insecticides were independent from each other. The crossbreeding progenies of a resistant and a susceptible DBMs showed higher tolerance to cartap which may attribute to the stronger total esterase activity as the broad-spectrum esterases may attack the thio-ester bond of cartap. So far, no resistance of DBM to the two registered benzoylarylureas i.e., teflubenzuron and chlorfluazuron has been recorded in Taiwan. The susceptible DBM possesses natural MFO activity which can degrade diflubenzuron, triflumuron and ethofenprox, while with only minimum effect on teflubenzuron, chlorfluazuron and fenvalerate. With the synergist piperonyl butoxide (pb), teflubenzuron and chlorfluazuron still exert better effect on the DBM than diflubenzuron and triflumuron. This may attribute to the fitness of insecticidal structure to the receptor of their toxic action. With the action of pb, ethofenprox performed better than fenvalerate in killing the DBM, which leads to the conclusion that the ether-bond structure in ethofenprox does not make it undesirable to the action receptor of the ester-bond synthetic pyrethroid.