Morphological and molecular taxonomy ofPythium longisporangiumsp. nov. isolated from the Burgundian region of France

During the course of an investigation on the Pythiaceous oomycetes occurring in the Burgundian vineyards, some species of Pythium possessing mainly hypogynous antheridia were found. These had been classified as oomycetes belonging to the ‘‘Pythium rostratum’’ group for a long time. Three of these isolates, having similar structures and growth, are very closely related to a recently described species, Pythium bifurcatum Paul. A close look at these, however, underlines some fundamental differences with the latter. Not all of them produce zoospores but have very large sporangia. The type specimen is F-1200 (B 76a) which is a medium-slow growing saprophyte. The sequence of the ITS region of the…