The Role of Eicosanoids in Nodulation Reaction Against Entomopathogenic Fungi in Spodoptera littoralis (Boisd.) (Lepidoptera: Noctuidae) Larvae

The study carried out the role of eicosanoids on nodulation reactions in Spodoptera littoralis larvae, against two fungal isolates (Beauvena bassiana 6646 and Metarhizium anisopliae 3293). When the larvae were infected with Beauvena bassiana 6646 and Metarhizium anisophite 3293, the insects showed a nodulation reaction to this infection. Injecting eicosanoid biosynthesis inhibitors just before the S. littoralis larvae were infected with fungal isolates reduced the nodulation response to fungal isolates. Specific applications, including inhibitors of enzymes in eicosanoid biosynthesis: dexamethasone (a phospholipase A2 inhibitor), indomethacin, naproxen. ibuprofen (cyclooxygenase inhibitors), esculet in (a lipoxygenase seinhibitor) and phenidone (both cyclooxygenase / lipoxygenise inhibitor) reduced formation of nodules in S. littoralis against fungal infection. These findings support the hypothesis that eicosanoids are involved in nodulation reactions against fungal infections in larvae of S. littoralis.