Meanwhile, it was noticed that toxicity of Bt-BS2 against susceptible mosquito larvae was higherthan that ofBt-BSI and this might be explained by the inserted direction of the binary toxin gene perhaps influencing its expression in the recipient strain.

• 此外，Bt-BS2的杀蚊毒力高于Bt-BS1，Bt-BS1和Bt-BS2对蚊幼虫毒力的不同可能是由于重组质粒上外源片段的插入方向影响二元毒素基因在受体菌中的表达水平的缘故。