寄主植物对二斑叶螨解毒酶活性的诱导作用

目的]明确不同蔬菜寄主对二斑叶螨解毒酶活性的诱导影响,为叶螨的寄主适应性及叶螨对寄主的抗性机制研究提供基础.方法]将饲养在菜豆上的二斑叶螨分别转移到黄瓜、甘蓝和茄子上饲养3代后,测定包括菜豆在内的4种不同寄主植物对叶螨体内解毒酶系活性的诱导影响.结果]取食不同寄主植物的二斑叶螨体内解毒酶系活性差异显著.从菜豆寄主转养到黄瓜、甘蓝和茄子上后,后3个寄主上叶螨种群体内谷胱甘肽S-转移酶(GST)活性显著下降,茄子上种群活性最低,菜豆种群是茄子种群的2.75倍；而后3个寄主种群的乙酰胆碱酯酶(AChE)比活力显著上升,茄子种群最高,是菜豆种群的6.03倍.4种供试寄主植物的二斑叶螨种群中,在黄瓜寄主上羧酸酯酶(CarE)和多功能氧化酶(MFO)活性显著高于其他3种寄主植物,CarE活性的高低顺序为黄瓜＞菜豆和甘蓝＞茄子,而MFO活性为黄瓜＞茄子和菜豆＞甘蓝.结论]取食不同寄主植物可诱导二斑叶螨体内的解毒酶系活性发生不同程度的变异,这可能是二斑叶螨对寄主具有广泛适应性的生理基础之一.

Induction effects on the detoxification enzymes of Tetranychus urticae from different host plants

Objective] Induction effects of different vegetable plants on the detoxification enzymes of Tetranychus urticae were analyzed to provide the basis for the host adaptation and its resistance mechanisms.Method] The detoxification enzymes of T.urticae from different host plants were measured when they were transferred to bean,cucumber,cabbage,and eggplant for 3 generations from bean plants.Result] There were significant differences in the detoxification enzymes of the 4 different host plants.The glutathione S-transferase(GST) activities of T.urticae on cucumber,cabbage,and eggplant decreased dramatically compared to that of bean population.The GST activities were the lowest on eggplant and the activities on bean were 2.75-fold higher than that on eggplant.Compared to bean population,the acetylcholinesterase(AChE) increased significantly on the other 3 plants,and the highest activities existed on eggplant and the lowest on bean,showing 6.03-fold differences.Among the 4 plants,the activities of carboxylesterase(CarE) and mixed function oxidase(MFO) of cucumber population were significantly higher than those of the other three host plants.The activities of CarE and MFO from high to low were as followed: cucumber>bean or cabbage>eggplant,and cucumber>eggplant or bean>cabbage,respectively.Conclusion] There were different variations in the activities of detoxification enzymes from T.urticae when they were reared on different host plants,which was probably one of the physiological bases for wide host adaptation of T.urticae.