Abstract
The ultrastructural effects of pyridalyl on the epidermal cells of S. litura larvae and cultured Sf9 cells were observed. In epidermal cells, hydropic degeneration containing swollen mitochondria, dilated rough endoplasmic reticulum, dilated Golgi apparatus, shrunken nuclei and increase of unidentified clear granules appeared 6 hr after treatment. In Sf9 cells, swelling of mitochondria was observed 4–6 hr after treatment, and then the cells finally entered hydropic degeneration. Since the time course of such ultrastructural changes was parallel to that of poisoning symptoms in the larvae, these effects were thought to be related with insecticidal action.
