Liu Xiaoxia, Zhang Qingwen, Xu Baoliang, Li Jiancheng
Department of Entomology, College of Agronomy and Biotechnology, China Agricultural University, Beijing 100094, PR China.
Pest Manag Sci. 2006 Aug;62(8):729-37. doi: 10.1002/ps.1229.
In the laboratory, the percentage mortality and pupation of Helicoverpa armigera (Hübner) were investigated when larvae were exposed to Cry1Ac of Bacillus thuringiensis Berliner, nuclear polyhedrosis virus of H. armigera (HaNPV) or Cry1Ac and HaNPV together. The results revealed that interactions between Cry1Ac and HaNPV varied with bioassay method and concentration of the suspension. When larvae were infected using a suspension containing both HaNPV and Cry1Ac, most combinations of Cry1Ac (62.5, 125 and 250 microg mL(-1)) and HaNPV (1.2 x 10(6), 6.0 x 10(6) and 3.0 x 10(7) PIB mL(-1)) showed an antagonistic effect. In the bioassay procedure where larvae were force fed diet containing Cry1Ac 48 h after being infected by HaNPV, interaction between Cry1Ac (0.5, 1, 2, 4 and 8 microg mL(-1)) and HaNPV (6.0 x 10(6) and 3.0 x 10(7) PIB mL(-1)) showed an additive effect, while combinations of Cry1Ac (0.5, 1, 2 and 4 microg mL(-1)) and HaNPV (1.2 x 10(6) PIB mL(-1)) showed an antagonistic effect. In the bioassay procedure where larvae being infected by HaNPV were fed on Cry1Ac diet from neonate to death or pupation, the results suggested that Cry1Ac and HaNPV showed an additive interaction. The percentage mortality was lower in the treatment of larvae infected by transgenic Bt cotton leaf discs containing HaNPV suspension than in the treatment of larvae by conventional cotton leaf discs containing HaNPV, while the pupation rate was higher. The combination of Bt cotton and HaNPV showed antagonism. The present results showed that a combination of Cry1Ac and HaNPV usually resulted in mortality levels greater than in the case of Cry1Ac but not greater than with the virus alone.
在实验室中，研究了棉铃虫（Helicoverpa armigera (Hübner)）幼虫暴露于苏云金芽孢杆菌（Bacillus thuringiensis Berliner）的Cry1Ac、棉铃虫核型多角体病毒（HaNPV）或Cry1Ac与HaNPV组合时的死亡率和化蛹率。结果表明，Cry1Ac与HaNPV之间的相互作用因生物测定方法和悬浮液浓度而异。当使用同时含有HaNPV和Cry1Ac的悬浮液感染幼虫时，Cry1Ac（62.5、125和250 μg mL(-1)）与HaNPV（1.2×10(6)、6.0×10(6)和3.0×10(7) 个多角体/mL）的大多数组合显示出拮抗作用。在HaNPV感染幼虫48小时后强制喂食含Cry1Ac饲料的生物测定程序中，Cry1Ac（0.5、1、2、4和8 μg mL(-1)）与HaNPV（6.0×10(6)和3.0×10(7) 个多角体/mL）之间的相互作用显示出相加作用，而Cry1Ac（0.5、1、2和4 μg mL(-1)）与HaNPV（1.2×10(6) 个多角体/mL）的组合显示出拮抗作用。在从幼虫新生期到死亡或化蛹期间用含Cry1Ac饲料喂养被HaNPV感染的幼虫的生物测定程序中，结果表明Cry1Ac和HaNPV显示出相加相互作用。用含HaNPV悬浮液的转基因Bt棉叶盘感染幼虫的处理组的死亡率低于用含HaNPV的常规棉叶盘处理幼虫的处理组，而化蛹率更高。Bt棉与HaNPV的组合显示出拮抗作用。目前的结果表明，Cry1Ac与HaNPV的组合通常导致的死亡率水平高于Cry1Ac单独作用时，但不高于单独使用病毒时。
