Bio-activity of propiconazole against larvae and cells of Spodoptera litura

In order to search lead compound of insecticide, cytotoxicity of 11 kinds of pesticides against Spodoptera litura cells were studied. The results showed that the cytotoxicity of propiconazole was the highest. The LC_ 50 values of propiconazole against S.litura cell were 23.89μg/mL and 13.62μg/mL after treated for 24h and 48h respectively. After 0.5μg/larva propiconazole had been injected into the 4th instar larvae of S.litura for 24h and 48h, the reduced rates of blood corpuscle of larvae were 19.67% and 21.38%, and the reduced rates of blood content were 20.42% and 23.87% respectively. Furthermore, 0.5μg/larva and 1.0μg/larva propiconazole could depress the larvae weight of S.litura obviously. When treated with propiconazole for 48h and 72h, the LD_ 50 values of propiconazole against 4th instar larvae of S. litura were 0.91μg/larva and 0.63μg/larva respectively. It is firstly proved that propiconazole has a high toxicity against S. litura cell and S. litura larva in laboratory, which showed the possibility for propiconazole analog controlling insect pests.