The present invention relates to a method for controlling powdery mildew on ornamental and/or vegetable plants without causing phytotoxicity to the plants, comprising applying a composition comprising fenpropidin and penconazole to the plants in a fungicidally effective amount. It also relates to a synergistic fungicidal composition comprising fenpropidin and penconazole.本發明係關於一種控制觀賞植物及/或蔬菜植物上之白粉病而不對植物造成植物毒性之方法,其包含以殺真菌有效量向植物施用包含苯鏽啶(fenpropidin)及平克座(penconazole)之組成物。本發明亦係關於一種協同殺真菌組成物,其包含苯鏽啶及平克座。