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Related to oidium: Thamnidium


, pl.


(ō-id'ē-ŭm, ō-id'ē-ă),
Formerly used term for arthroconidium.
[Mod. L. dim. of G. ōon, egg]


n. pl. oid·ia (-ē-ə)
1. A thin-walled spore produced asexually by fragmentation in certain filamentous fungi.
2. Any of various fungi that cause powdery mildew.


Uncertain;an obsolete genus of pathogenic fungi that have been reclassified under various other genera.
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References in periodicals archive ?
Reactive oxygen species generation and peroxidase activity during Oidium neolycopersici infection on Lycopersicon species.
That is, until phylloxera and oidium destroyed most vineyards on the Portugese island at the turn of the twentieth century.