International Journal of Tropical Insect Science

, Volume 8, Issue 1, pp 107–110 | Cite as

Toxicity of Two Bacterial Insecticides Against the Larvae of Mosquito Culex pipiens and their Action on the Reproductive Potential and Morphometric Characteristics of Surviving Females

  • M. S. Saleh
  • N. L. Kelada
  • A. A. Al-Fazairy
Research Article


The larvicidal activity of two entomopathogenic bacteria Bacillus thuringiensis H-14 and B. sphaericus 1593 against mosquito larvae of Culex pipiens has been evaluated. According to LC50 values obtained, B. thuringiensis (4.6 × 105 spores/ml) proved to be highly pathogenic to fourth instar larvae than fi. sphaericus (4.2 × 106 spores/ml).

Larval treatment with LC50 levels of both pathogens affected the reproductive potential of surviving adults during two successive gonotrophic cycles. These treatments caused insignificant changes in some basic morphometric characteristics of mosquito females that developed from surviving larvae.

Key Words

Bacillus thuringiensis B. sphaericus Culex pipiens mosquito larvae mosquito females reproductive potential morphometric characteristics 


L’activité larvicide des deux entomopathogènes Bacillus thuringiensis H-14 et B. sphaericus 1593 a été evaluée sur les larves de Culex pipiens. D’après les valeurs de LC50 obtenues, B. thuringiensis (4.6 × 105 spores/ml) est plus pathogène sur les larves du quatrieme stade que B. sphaericus (4.2 × 106 spores/ml).

Le traitement des larves par les deux pathogènes, à un dosage correspondant a la LC50 a áffecté la reproduction des adults survivants durant deux cycles gonotrophiques successifs. Ces traitements, ont causé des changements insignifiants sur la morphologie des adultes survivants.


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Copyright information

© ICIPE 1987

Authors and Affiliations

  • M. S. Saleh
    • 1
  • N. L. Kelada
    • 1
  • A. A. Al-Fazairy
    • 1
  1. 1.Entomology Division, Faculty of AgricultureUniversity of AlexandriaAlexandriaEgypt

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