Effects of Insect Growth Inhibitor Alsystin on Culex quinquefasciatus Say (Culicidae: Diptera)

  • Z. H. Mohsen
  • N. S. Mehdi
Research Article


The insect growth inhibitor Alsystin (SIR 8514) was tested for its effects against the immature and adult stages of Culex quinquefasciatus Say under laboratory conditions. A linear correlation was revealed between concentration and larval and pupal mortality. Larval mortality increased from 5% at 0.005 ppm to 74.4% at 0.1 ppm of Alsystin. Complete inhibition of adult emergence resulted after larval exposure to 0.05 ppm. Exposure of eggs (at 0 hr of age) to 0.1 ppm and 10.0 ppm of Alsystin, resulted in considerable decrease of hatching from 87.0% in the control to 61.0% at 1.0 ppm and to 48.0% at 10.0 ppm. The adults of C. quinquefasciatus were seen attracted to the bowls containing 50.0 ppm and 100.0 ppm of Alsystin. However, landing adults died within a short period of time. The different types of deformation in the larva, pupa and adult as a result of exposure to Alsystin are illustrated.

Key Words

Insect growth inhibitor Alsystin (SIR 8514) effect on egg effect on larva effect on pupa effect on adult Culex quinquefasciatus deformation adult attraction 


L’effect d’Alsystin (SIR 8514), un inhibiteur de la croissance d’insecte, sur les différents stades du développement de Culex quinquefasciatus Say avait été, étudié au laboratoire. Nous avons démontré une corrélation direct entre la concentration d’Alsystin et la mortalité de larves et de nymphes. Au 0.1 ppm, Alsystin trouvé d’être bien toxique au larves(mortalité maximum 74.4%), en plus, une diminution considérable de la transformation de ces larves au nymphes est obtenue. L’inhibition total de l’emersion d’adults avait été éprouvé après le traitment de larves avec 0.05 ppm a’Alsystin, quant aux oeufs (au temp zero) mis en contact avec 1.0 ppm et 10.0 ppm de ce substance, le pourcentage d’éclosion est réduit (61.0 et 48.0% respectivement) en comparison avec le témoin (87.0%). De plus, les adults sont attiré par deux concentration d’Alsystin (50.0 et 100.0 ppm). D’autre part des adults a l’état de débarquement n’étaient pas capable de survivre les malformations provoquer par Alsystin parmis les larves, nymphes et adults sont montré


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Copyright information

© ICIPE 1989

Authors and Affiliations

  • Z. H. Mohsen
    • 1
  • N. S. Mehdi
    • 1
  1. 1.Biological Research CenterScientific Research Council, JadiriyaBaghdadIraq

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