title: [Characterization of Bacillus thuringrensis var. israelesis larvicide granules to larvae of mosquitoes].
abstract: OBJECTIVE
  To develop a new formulation of Bacillus thuringrensis var. israelesis (Bti) granules and assess its effect on mosquito control.
  
  
  METHODS
  The Bti granule formulation was produced by coating Bti liquid on the surface of the carrier. and imitation tests, persistence tests and field tests were carried to assess its mosquito larvicidal effect, extended period and stability.
  
  
  RESULTS
  A strain of Bti isolated from field had high toxicity to mosquito larvae and its LC50 values for larvae of Culex pipiens pallens and Aedes aegypti were 0.461 0 microl/L and 1.713 3 microl/L respectively. The developed 216 ITU/mg Bti granules had a control effect of 83.3%-100% to larvae of C. pipiens pallens at the dosage of 1-3 g/m2, and 72.7%-100% to A. aegypti at the dosage of 3-5 g/m2. When the 3rd instar larvae of C. pipiens pallens were put in the water that was treated with the granules at the dosage of 0.5 g/m2 13 days before, the larval mortality still reached to 55.3%. The field tests showed that with the treatment of 2-4 g/m2 Bti granules, the control effects on the larvae were high from 92.4% to 100% within the first 3 days and about 51.6%-75.7% after 20 days.
  
  
  CONCLUSIONS
  The developed new formulation of Bti granules with the isolated strain has a preferable control effect on mosquito larvae and reveals a longer persistence and better stability than liquid formulation in the field tests.
authors.affiliation: Jiangsu Lixiahe Institute of Agriculture Science, Yangzhou 225007, China.
authors.forename: Jian
authors.initials: J
authors.lastname: Xu
authors.forename: Song
authors.initials: S
authors.lastname: Zhao
authors.forename: Qin
authors.initials: Q
authors.lastname: Liu
authors.forename: Jian-Hang
authors.initials: JH
authors.lastname: Qi
authors.forename: Chuang-Ming
authors.initials: CM
authors.lastname: Li
authors.forename: Yan
authors.initials: Y
authors.lastname: Wang
authors.forename: Jun
authors.initials: J
authors.lastname: Sun
authors.forename: Guang-Jie
authors.initials: GJ
authors.lastname: Han
authors.forename: Tan-Bin
authors.initials: TB
authors.lastname: Ma
mesh_terms: D000818:Animals; D001407:Bacillus / Q000254:growth & development / Q000502:physiology*; D009033:Culicidae / Q000382:microbiology*; D046508:Culture Techniques; D007814:Larva / Q000382:microbiology; D009032:Mosquito Control / Q000379:methods*; D010572:Pest Control, Biological / Q000379:methods*; D013997:Time Factors