Abstract
The effects of ten major fungicides commonly used in paddy fields to control hyphal growth and spore germination of Erynia delphacis were examined. All fungicides inhibited both hyphal growth and spore germination of the fungus on the medium. Isoprothiolane inhibited hyphal growth and secondary spore formation even at low concentrations. Spraying isoprothiolane directly onto the green rice leafhopper (Neophotettix cincticeps) inhibited fungal growth, but spraying the fungicide onto rice plants, did not inhibit fungal growth. When the fungicide was sprayed on paddy fields, the population of diseased insects decreased. However, the population of the green rice leafhopper increased.
