Differential Susceptibility of Parasitized and Unparasitized Larvae of Spodoptera Littoralis (Boisd.) (Lepidoptera: Noctuidae) to Its Nuclear Polyhedrosis Virus

  • Ahlam A. M. Al-Fazairy
  • E. M. Hegazi
  • Hedaya H. Karam
  • Lamya M. Abo-Abd-Allah
Research Article


Rates of virus-induced mortality and values of the LC50 and LT50 showed that, in general, parasitism by Microptitis rufiventris Kok. increased the susceptibility of the Egyptian cotton leafworm, Spodoptera littoralis second-instar larvae to its nuclear polyhedrosis virus (SLNPV). By comparing the LC50values, data revealed that virus-infected parasitized larvae were ca. 3.5 and 4.8 times more susceptible to SLNPV than virus-infected unparasitized ones at 8 and 12 days post-infection, respectively. Also, in virus-infected unparasitized larvae, the time required to attain a 50% mortality was significantly longer than that in virus-infected parasitized ones.

Key Words

Spodoptera littoralis Microplitis rufiventris nuclear polyhedrosis virus susceptibility 


Virus-induirés mort (%) et les valeurs de LC50 et LT50 révélé que parasitism par Microplitis rufiventris Kok. augmenta le sensible d’une feuille de coton égyptien, Spodoptera littoralis II - stade larvés au le noyau polyhedrosé virus (NPV). Les valeurs de LC50 ont révélé que virus - infectés parasitiés larvés était plus sensible 3.5 et 4.8 fois que les virus - infectés non-parasitiés larvés après 8 et 12 jours d’infection respectivement. Aussi, pour les virus - infectés non-parasitiés larvés, la valeur de LT50 était significantly longuer que les virus-infectes parasitiés larvés.


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Copyright information

© ICIPE 1993

Authors and Affiliations

  • Ahlam A. M. Al-Fazairy
    • 1
  • E. M. Hegazi
    • 1
  • Hedaya H. Karam
    • 1
  • Lamya M. Abo-Abd-Allah
    • 1
  1. 1.Faculty of Agriculture, Plant Protection Department, Entomology DivisionUniversity of AlexandriaAlexandriaEgypt

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