title: [Experimental observation of toxic effect of Bacillus thuringiensis var. israelensis against Aedes, Culex and Anopheles larvae].
abstract: OBJECTIVE
  To evaluate the toxic effect of Bacillus thuringiensis var. israelensis (Bti) wettable powder against Aedes, Culex and Anopheles larvae.
  
  
  METHODS
  The biological assay was applied to test the lethal concentration of 50% (LC50) of Bti wettable powder against Aedes, Culex and Anopheles larvae.
  
  
  RESULTS
  The LC50(s) of Bti wettable powder against Aedes albopictus, Culex pipiens pallens and Anopheles sinensis larvae were 0.104, 0.160 microg/ml and 0.324 microg/ml, respectively; its biological potencies against them were 0.125, 0.192 IU/ml and 0.389 IU/ml, respectively. The LC50(s) of continuous contact of Bti wettable powder with An. sinensis stage III larvae for 1, 2 d and 3 d were 0.324, 0.092 microg/ml and 0.032 microg/ml, respectively, and its biological potencies were 0.389, 0.110 IU/ml and 0.038 IU/ml, respectively. The LC50(s) of the bacteria against An. sinensis stage I , II, III, IV were 0.024, 0.137, 0.324 microg/ml and 0.450 microg/ml, respectively, and the biological potencies were 0.029, 0.164, 0.389 IU/ml and 0.540 IU/ml, respectively.
  
  
  CONCLUSIONS
  Bti wettable powder has a good toxicity to Aedes, Culex and Anopheles larvae, especially for the latter two. It is better to apply the bacteria at the early stage of mosquito larvae.
authors.forename: Ju-Lin
authors.initials: JL
authors.lastname: Li
authors.forename: Guo-Ding
authors.initials: GD
authors.lastname: Zhu
authors.forename: Hua-Yun
authors.initials: HY
authors.lastname: Zhou
authors.forename: Jian-Xia
authors.initials: JX
authors.lastname: Tang
authors.forename: Jun
authors.initials: J
authors.lastname: Cao
mesh_terms: D000330:Aedes / Q000254:growth & development; D000818:Animals; D000852:Anopheles / Q000254:growth & development; D001413:Bacillus thuringiensis; D003465:Culex / Q000254:growth & development; D009033:Culicidae / Q000254:growth & development*; D007814:Larva / Q000254:growth & development; D010572:Pest Control, Biological