title: [Influence of biotic factors on the efficacy of Bacillus thuringiensis var. Israelensis against Aedes aegypti (Diptera: Culicidae)].
abstract: BACKGROUND
  Bacillus thuringiensis H-14 has shown high efficacy on Aedes aegypti larvae. But a number of factors could affect its effectiveness. Knowing these factors is of vital importance for improving the application parameters in real conditions in order to guarantee the treatment's efficiency and to reduce environmental impact.
  
  
  OBJECTIVE
  to evaluate the influence of some biotic factors on Bacillus thuringiensis H-14 efficacy against Aedes aegypti (Rockefeller).
  
  
  METHODS
  an experimental study was conducted following the WHO guidelines. The influence of the food availability, the larval density and the larval staging was evaluated on laboratory bioassays. A commercial Bacillus thuringiensis H-14 formulation against a reference Aedes aegypti strain was used.
  
  
  RESULTS
  the efficacy of Bacillus thuringiensis H-14 decreased in a linear manner with increasing larval density and development stage. This could be related to food intake and availability of the active principle. Competition in food intake resulted in lower efficacy of Bacillus thuringiensis H-14 applications.
  
  
  CONCLUSIONS
  the Bacillus thuringiensis H-14 efficacy was affected for the availability of food, the larval development stage and the larval density, so all this should be borne in mind when applying the biolarvicide in situ.
authors: Laboratorio de Producciones Biofarmacéuticas y Químicas (LABIOFAM), La Habana, Cuba. sharp@princesa.pri.sld.cu
authors: Carlos Orlando
authors: CO
authors: Corbillón Porraspita
authors: Aileen
authors: A
authors: González Rizo
authors: Zulema
authors: Z
authors: Menéndez Díaz
authors: Ariamys
authors: A
authors: Companioni Ibañez
authors: Rosa Yirian
authors: RY
authors: Bruzón Aguila
authors: Manuel
authors: M
authors: Díaz Pérez
authors: René
authors: R
authors: Gato Armas
mesh_terms: D000330:Aedes / Q000382:microbiology*; D000818:Animals; D001413:Bacillus thuringiensis / Q000502:physiology*; D010572:Pest Control, Biological / Q000379:methods*