- Forms a protective barrier on the plant surface that prevents spore germination eg. Dithane, Bravo, thiram
- Moves in the plant from point of application across the leaf or into new growth. Can move from roots to above ground parts. Prevents spores from germinating or kills them soon after germination. Eg. Tilt, Baytan, Raxil, Quadris, Ridomil.
ERADICATIVE (Curative)- kills fungus already present. Some systemic fungicides have some curative activity