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Between August and September 2017, zonate leaf spots with severe defoliation were observed on Parthenocissus tricuspidata in Gimcheon, Korea. The initial symptoms included water-soaked, gray to grayish brown, circular or irregular-shaped leaf spots. As the disease progressed, the spots enlarged, coalesced, and became cream-colored with characteristic target-shaped rings, leading to leaf blight and premature defoliation. Based on cultural and morphological characteristics, the fungus associated with the symptoms was identified as Grovesinia moricola. The identity of this fungus was confirmed by analyzing sequences of the internal transcribed spacer region of ribosomal DNA. The pathogenicity of the isolate was demonstrated by artificial inoculation. To our knowledge, this is the first report of G. moricola occurring on P. tricuspidata globally as well as in Korea.

During the extensive forays for discovering the biodiversity of phytopathogenic fungi in Korea, powdery mildew-affected purple coneflowers (Echinacea purpurea) were frequently found. Since 2004, nine samples have been deposited in the Korea University Herbarium. The initial symptoms include white, evanescent mycelia and irregular patches on mature leaves. Mild symptoms in the form of discolored lesions are also noticed on the stem and petal of the affected plants. Based on the morphological characteristics of the anamorph and the phylogenetic analysis of the internal transcribed spacers (ITS) and large subunit (LSU) rDNA sequences, the causal fungus was identified as Podosphaera xanthii. This is the first report that identifies the causal agent of powdery mildew disease affecting purple coneflower in Korea.