中文摘要：

目的探讨苏云金杆菌以色列亚种（Bti）对中华按蚊不同龄期幼虫的杀灭效果。方法采用幼虫浸渍法,26℃环境下,用浓度为2、4、6、8、10、12、14 mg/L的Bti药液,分别对Ⅰ~Ⅳ龄期的中华按蚊幼虫进行实验测定。结果 Bti对微山湖湿地中华按蚊Ⅰ龄期幼虫杀灭作用最佳。其对中华按蚊Ⅰ~Ⅳ龄幼虫的LC_（50）值分别为6.11、8.03、9.66和10.50 mg/L。微山湖湿地Ⅰ~Ⅳ龄幼虫相对实验室敏感幼虫抗性倍数分别为1.15、1.08、1.11和1.12倍。结论 Bti对微山湖湿地中华按蚊幼虫均有不同程度的杀灭作用,同样浓度下幼虫龄期越小,杀灭效果越显著。而且Bti对微山湖湿地幼虫的杀灭效果与实验室敏感品系相差不大,提示当中华按蚊对化学杀虫剂产生抗性时,应用Bti等生物杀虫剂是较好的选择。

英文摘要：

Objective To study the insecticidal effect of Bacillus thuringiensis subsp, israelensis （Bti）against larvae of Anopheles sinensis from Weishanhu Wetlands, Shandong Province. Methods The method of larvae immersed in liquid was adopted under 26℃, ascertaining the killing effect of different concentrations of Bti against all instar of Anopheles sinensis larvae.Results Bti held the best killing effect on Anopheles sinensis first larvae from Weishanhu wetlands. The LC50 values of Bti to the first, second, third and fourth instar larvae were 6. 11,8.03,9. 66 and 10. 50 mg/L, respectively.The resistance ratios of Anopheles sinensis larvae of the four instars from Weishanhu Wetlands were 1.15,1.08,1.11 and 1.12 ,respectively. Conclusion Bti can kill all ages of Anopheles sinensis larvae, at the same concentration, the smaller the ages of Anopheles sinensis ,the more remarkable killing effect of Bti was.Additionally, it appears that the killing effect of Bti against Anopheles sinensis larvae at Weishanhu wetlands are similar as laboratory strain larvae, which suggest that apply biological insecticides such as Bti would be a better choice, when Anopheles sinensis are resistant to chemical insecticides.