Histopathology of Culex pipiens (Linée, 1753) (Diptera, Culicidae) larvae exposed to the aqueous extract of Eucalyptus globulus l'Hér, 1789 (Myrtaceae)

Abstract

Eucalyptus globulus was tested for its larvicidal activity against the mosquito larvae Culex pipiens. The application of the aqueous extract at (0.5 g / l, 2 g / l, 5 g / l and 8 g / l) concentrations caused the remarkable mortality of 83% for the larvae that were treated at 8 g / l dosage and observed after 72 hours of contact. After calculating the LD50 (27.6 g / l after 24hours, 13.45 g / l after 48 hours and 3.57 g / l after 72 hours of exposure). Larvae of Culex pipiens treated with the aqueous extract of Eucalyptus globulus suffer important damages of midgut that occur over time. After 24 hours, the cells burst and the cytoplasmic contents move to the intestinal lumen, leading to death.