Grape downy mildew
primarily as oospores in fallen leaf litter, though in milder climates it can also persist as mycelium within infected buds and canes. In spring, oospore g [...] post-infection (depending on temperature and humidity), the disease is often well-established before it can be visually detected in the field. Leaf symptoms [...] e, characteristic ‘oil spots’ on the upper surface of young, actively growing leaves, followed by downy white growth on the underside, are typical early