论文部分内容阅读
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。
Objective To investigate the killing effect of Bti of Bacillus thuringiensis on larvae of different stages of Anopheles sinensis. Methods The larvae were immersed in Bti solution of 2,4,6,8,10,12,14 mg / L at 26 ℃ for the first to fourth instar larvae of Anopheles sinensis . Results Bti had the best killing effect on the first instar larvae of Anopheles sinensis in Weishan Lake wetland. The LC 50 value of Anopheles sinensis Ⅰ ~ Ⅳ instar larvae were 6.11, 8.03, 9.66 and 10.50 mg / L, respectively. The sensitive multiples of susceptible larvae of stage I to IV larvae in Weishan Lake wetlands were 1.15,1.08,1.11 and 1.12 times respectively. Conclusion Bti had different degrees of killing effects on Anopheles sinensis larvae in Weishan Lake wetlands. The smaller the larvae age, the more obvious the killing effect was. Moreover, the killing effect of Bti on Weishan Lake wetland larvae was similar to that of laboratory sensitive strains, suggesting that when Bipolaris was resistant to chemical insecticides, the application of Bti and other biocides was a better choice.