Isolation and Identification of Two Unreported Fungi in Korea: Dothidea insculpta and Metarhizium rileyi

Than Naing  Moe1   Kallol Das1   Avalos-Ruiz  Diane1   In-Kyu  Kang2   Seung-Yeol  Lee13,*   Hee-Young Jung   



In this study, the fungal strains KNU-Gunwi 2B and KNU-SOT5 were isolated from root-soil in a hillside and the cherry tree bark (Prunus serrulata), respectively from Gyeongbuk province in Korea. The strain KNU-SOT5 produced dark brown chlamydospores that were smooth to lightly rough-walled, globose to ellipsoidal, and the conidia were aseptate, guttulate, mostly fusiform with a diameter of 5.3-17.6×4.2-7.0 μm. Strain KNU-Gunwi 2B produced phialides that were smooth-walled, cylindrical with semi-papillate apices and the conidia were pale-green, broadly ellipsoid, and sometimes cylindrical with a diameter of 4.4-8.0×2.3-4.0 μm. The strain KNU-SOT5 and KNU-Gunwi 2B were resolved based on cultural and morphological characteristics, along with the phylogenetic analysis using the small subunit (SSU), large subunit (LSU), and internal transcribed spacers (ITS) regions. The fungal strains KNU-SOT5 and KNU-Gunwi 2B were identified as Dothidea insculpta and Metarhizium rileyi, which have not been reported in Korea.

Figures & Tables

Fig. 1. Morphological characteristics of Dothidea insculpta KNU-SOT5. A, colonies on potato dextrose agar (PDA) after 5 days; B, large colonies on PDA after 2 wks; C, feathery mycelium and blackish conidiomata-like structures observed under a stereomicroscope; D, E, conidiophores; F, melanized hyphae developing into chlamydospores; G, conidia. Scale bars: C=50 μm; F=20 μm, D, E=10 μm, G=5 μm.