Downy mildew is a major disease of grapevines caused by the fungal-like oomycete Plasmopara viticola. This species is unique to grapevines and is established in all Australian grapegrowing districts. It is spread by wind and water and favourable conditions for infection and disease development occur in warm wet weather, especially in late spring and early summer. In most districts, vines are at greatest risk from 3–6 weeks after budburst until berries are pea-sized. Inadequate control of downy mildew can result in severe crop losses. Most commercial varieties are susceptible to this disease. Essential components for strategic management of downy mildew include prediction of infection based on weather events, monitoring the vineyard for symptoms of infection, knowing the disease cycle, and understanding how cultural management practices and registered agrochemicals affect disease control. This page provides links to help growers understand and manage this grapevine disease.
Fact sheets and website links
- Downy mildew characteristics (AWRI viti-note)
- Downy mildew management (AWRI viti-note)
- Downy mildew monitoring (AWRI viti-note)
- Downy mildew symptoms (AWRI viti-note)
- Wine Australia’s resources on downy mildew
- Control strategies for downy mildew and Botrytis (AWRI webinar 9 November 2018)
- Phosphorous acid