This vine disease (also called collar rot, root neck rot or lat. Dematophora necatrix) is caused by a species of Pythium fungus. It is favoured by waterlogging of mainly young vines. The affected root areas are covered with the white, cobweb-like fungus. In many sources, however, this disease is described under the collective term root rot. See also under vine enemies.
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Diplom-Sommelier, Weinakademiker und Weinberater, Volders (Österreich)