Term for two dangerous vine diseases caused by fungi. They were first introduced to Europe in the second half of the 19th century with contaminated vine material from North America. Both types of fungi are biotrophic parasites, which means that they feed on the living cells of the infected host. The two powdery mildew diseases are often confused, not so much because of the symptoms, which are fairly obvious, but because of the confusingly similar names. There are plant-specific mildews, e.g. for apples, peas, cucumbers, roses, spinach and grapevines. The fungi are strictly host-specific, i.e. they can only live on their host or hosts.
I have great respect for the scope and quality of the wein.plus encyclopaedia. It is a unique place to go for crisp, sound information on terms from the world of wine.
Dr. Edgar Müller
Dozent, Önologe und Weinbauberater, Bad Kreuznach