转双抗三倍体毛白杨对舞毒蛾幼虫中肠解毒酶的影响

Effect of Bt and PI Triploid Transgenic Chinese White Poplar On Detoxicification Enzyme of Gypsy Moth Larvae

[目的]为转基因植物的合理利用提供理论依据。[方法]以转Bt基因和慈姑蛋白酶抑制剂基因三倍体毛白杨叶片喂4～5龄舞毒蛾幼虫,对其中肠几种重要解毒酶的活性进行了测定。[结果]幼虫中肠酯酶的比活力变化是先升高后降低,24 h后达到高峰,而在48 h后,比活力明显下降;谷胱甘肽-S-转移酶的比活力是一直在升高。取食抗虫杨Pb1、Pb33和Pb47叶片48 h后的舞毒蛾幼虫中肠酯酶的比活力分别为取食CK幼虫酯酶比活力的62.9%、70.7%和74.5%;24 h后的幼虫中肠谷胱甘肽-S-转移酶的比活力分别比取食CK幼虫谷胱甘肽-S-转移酶比活力下降了25.7%、27.7%和17.9%。[结论]导致幼虫中肠解毒酶活性的改变可能是转基因叶片毒杀害虫的作用机制之一。

[Objective] The propose of study was to provide the theoretical basis for rational utilization of transgenic plant. [Method] The 4th-5th instar larvae of gypsy moth were fed by the leaves of triploid transgenic Chinese white poplar of transferring Bt gene and arrowhead proteinase inhibitor gene and the activities of several detoxification enzymes of gypsy moth were determined. [Result] The activity of intestine esterase in larvae was increased at first, arrived at the highest after fed with transgenic Chinese white poplar for 24 h and decreased after 48 h. The activities of glutathione-S-transferase （GST） rose all the time. The activities of intestine esterase in larvae after fed by the leaves of transgenic Chinese white poplar Pbl, Pb33 and Pb47 for 48 h were 62.9 %, 70.7 % and 74.5 % of that of CK and the activities of GST in larvae after fed by the leaves of transgenic Chinese white poplar Pbl ,Pb33 and Pb47 for 24 h were 25.7 %, 27.7 % and 17.9 % lower than that of CK. [Conclusion] The detoxification enzymes system in the midgut of larvae was changed and further toxic reaction of Bt protein could take place, which may be one of the important mechanisms of poisoning the pests by Bt transgenic Chinese white poplar.