Origin of downy mildew
Examples from the Web for downy mildew
Downy-mildew, like black-rot, spreads most rapidly and does most injury in hot, wet weather.
The berries, however, do not become soft and shrunken as when attacked by the downy-mildew.
Downy-mildew (Plasmopara viticola) rivals black-rot for first place among fungous diseases of the grape.