Fludioxonil is a contact fungicide. It is effective against a wide range of ascomycete, basidiomycete and deuteromycete fungi. As a cereal seed treatment, it controls seed- and soil-borne diseases and gives particularly good control of Fusarium roseum and Gerlachia nivalis in small-grain cereals. As a potato seed treatment, fludioxonil gives broad-spectrum control of diseases including Rhizoctonia solaniwhen used as recommended. Fludioxonil does not affect seed germination. Applied as a foliar fungicide, it provides high levels of Botrytis control in various crops. The fungicide controls diseases on stems, leaves, flowers and fruits. Fludioxonil is active against benzimidazole-, dicarboximide- and guanidine-resistant fungi.