Sung Eun Cho

Choanephora flower rot caused by Choanephora cucurbitarum on Abelmoschus manihot

In August 2013, blossom blight and wet rot were observed on flowers of Abelmoschus manihot in a private garden in Hongcheon County, Korea. The fungus initially infected fading flower petals, then expanded to encompass entire flowers and finally resulted in flower desiccation and fall. The causal fungus was identified by morphological characterization and molecular analysis as Choanephora cucurbitarum. Pathogenicity tests were conducted twice with similar results. To our knowledge, this is the first report, globally, of C. cucurbitarum on A. manihot.

First report of Golovinomyces cichoracearum associated with powdery mildew on Helianthus tuberosus in Korea

Helianthus tuberosus has been found to be infected with a powdery mildew fungus in Korea since 2000. The fungus was identified as Golovinomyces cichoracearum based on the morphological characteristics of the anamorph and ITS sequence analysis. This is the first record of Helianthus-Golovinomyces association in Korea.

Characterization of Erysiphe sp. causing powdery mildew on Saxifraga stolonifera in Korea

Powdery mildew on Saxifraga stolonifera is frequently observed in Korea, causing considerable damage to gardens. Based on the morphological characteristics of the conidial stage and sequence analyses of the internal transcribed spacer regions and 28S rDNA, the fungus associated with the powdery mildew was determined as Erysiphe sp. A mycological discussion on Erysiphe krumbholzii, a powdery mildew fungus on Saxifragaceae, is also provided. This information will aid in the understanding of known powdery mildews on Saxifragaceae.

First record of Podosphaera xanthii on Peperomia tetragona

In January 2017, Peperomia tetragona was found to be infected with a powdery mildew in Korea. No chasmothecia were observed. The fungus associated with foliar signs of powdery mildew was identified as Podosphaera xanthii using morphological characteristics of the anamorph and molecular analysis of ITS regions. This is the first report of powdery mildew infections on P. tetragona worldwide.

Morphological and molecular identification of Melampsora idesiae on Idesia polycarpa in Korea

During extensive surveys of phytopathogenic fungi in Korea, rust-infected leaves of Idesia polycarpa were found and deposited in the Korea University Herbarium. Seven of these samples were examined, and the fungus was identified as Melampsora idesiae on the basis of morphological characteristics. Analyses of the large subunit (LSU) rDNA region of three samples confirmed their placement in the Melampsora clade. In this paper, we provide the detailed morphological features and LSU sequences of M. idesiae for the first time.

Occurrence of powdery mildew caused by Erysiphe paeoniae on Paeonia suffruticosa

Since 2013, Paeonia suffruticosa (tree peony) shrubs in Korea have been found to be infected with powdery mildew. Phylogenetic analyses based on both ITS rDNA sequences and the morphological characters of the anamorph and teleomorph stages determined the powdery mildew to be Erysiphe paeoniae. This is the first case of E. paeoniae infection on a host plant in sect. Moutan of the genus Paeonia, and is the first report of powdery mildew occurring on P. suffruticosa worldwide. The occurrence of powdery mildew is a potential threat to the widespread ornamental plantings of P. suffruticosa. Information about the morphological and genetic characteristics of this disease may help Paeonia breeders, growers, and gardeners to monitor the disease.

First report of postharvest root rot caused by Rhizopus oryzae on Codonopsis lanceolata

Postharvest root rot of Codonopsis lanceolata was found at storage piles in a market in Seoul, Korea, 2012. Based on the morphological characteristics and molecular analyses of the ITS rDNA and D1/D2 region of the LSU, the causal fungus was identified as Rhizopus oryzae. This is the first report of Rhizopus-associated root rot on Codonopsis lanceolata.

First report of powdery mildew on Cissus rhombifolia caused by Erysiphe necator in the Czech Republic

Cissus rhombifolia was found to be infected with a powdery mildew for the first time in the Czech Republic in 2008. The fungus was identified as Erysiphe necator based on the morphological characteristics of the anamorph. This is the second report of E. necator infection of C. rhombifolia in Europe.