转Bt基因水稻表达的毒蛋白Cry1Ab在害虫及其捕食者体内的积累动态

在室内对转基因水稻KMD1中的Cry1Ab毒蛋白经食物链在几种主要害虫及其捕食性天敌体内的积累进行了研究。结果表明： 无论是水稻孕穗期还是成熟期，二化螟Chilo suppressalis连续取食KMD1或取食KMD1.36 h后移至对照品种秀水11上取食不同时间后，幼虫体内的Cry1Ab含量均随取食时间延长逐渐下降。稻眼蝶 Mycalesis gotama幼虫连续取食KMD1或在KMD1上取食两天后移至秀水11上继续取食不同时间，体内的Cry1Ab含量也都随取食时间延长而下降，但下降速度较二化螟更快。取食KMD1的二化螟和稻眼蝶幼虫的粪便中均检测到较高浓度的Cry1Ab，对照组中均无Cry1Ab。取食KMD1的二化螟幼虫血淋巴中检测到Cry1Ab，含量为3.5 ng/g。取食KMD1的褐飞虱 Nilaparvata lugens、稻蚜Sitobion avenae以及饲喂取食过KMD1的二化螟或稻眼蝶幼虫的拟水狼蛛Pirata subpiraticus体内都含有一定浓度的Cry1Ab，其中，拟水狼蛛体内的CrylAb含量以饲喂取食KMD1稻眼蝶幼虫的含量最高，约为饲喂取食KMD1二化螟幼虫的60倍。这些结果表明Cry1Ab可以沿水稻害虫天敌食物链传递。

Dynamics of Cry1Ab protein from transgenic Bt rice in herbivores and their predators

Levels of Cry1Ab protein in several herbivores and their predators through food chain from transgenic Bt rice (KMD1) were studied in the laboratory. The results showed that the levels of Cry1Ab in stripped stem borer (SSB) Chilo suppressalis continuously feeding on KMD1 or on Xushui 11 control rice after feeding on KMD1 for 36 h declined with time at the booting stage as well as at the maturing stage. Levels of Cry1Ab in Mycalesis gotama continuously feeding on KMD1 or on Xushui 11 control rice after feeding on KMD1 for two days declined with time, but more dramatically than those of SSB. High levels of Cry1Ab were detected in faeces of both C. suppressalis and M. gotama, but no Cry1Ab detected in their controls. 3.5 ng/g Cry1Ab was detected in the haemolymph of C. suppressalis feeding on KMD1. Different levels of Cry1Ab were all detected in brown planthopper (BPH) Nilaparvata lugens, rice aphid (RA) Sitobion avenae reared on KMD1, and wolf spider (WS) Pirata subpiraticus fed with preys that had ingested KMD1. The concentration of Cry1Ab protein in P. subpiraticus fed with M. gotama larvae reared on KMD1 was about 60 times higher than that in P. subpiraticus fed with C. suppressalis reared on KMD1 for 36 h, and no Cry1Ab protein was detected in their controls. These results indicated Cry1Ab protein could be transferred along food chain.