| Noun | 1. | Plasmodiophoraceae - family of fungi often causing hypertrophy in seed plants fungus family - includes lichen families class Oomycetes, Oomycetes - nonphotosynthetic fungi that resemble algae and that reproduce by forming oospores; sometimes classified as protoctists genus Plasmodiophora, Plasmodiophora - type genus of Plasmodiophoraceae comprising minute plant parasitic fungi similar to and sometimes included among the slime molds |