Powdery mildew is the common term for a group of plant diseases. In grapevines, the disease is caused by the fungus originally named Uncinula necator, now renamed Erysiphe necator.
Infection and subsequent disease development is influenced by many factors including the presence of infected grapevine tissue, spores, and the occurrence of particular weather conditions. Disease progress early in the season may be slow depending on weather conditions, but is not usually impeded in most areas of Australia.
Characteristics of Powdery Mildew – Vitinotes
Symptoms of Powdery mildew (with pictures) – Vitinotes
Managing Powdery Mildew – Vitinotes
Monitoring for Powdery Mildew – Vitinotes
Powdery mildew of grapes in Western Australia (practical outlines)
PMapp: A mobile app for assessing powdery mildew (with links to downloads from apple and android sites)