First report of six Sordariomycetes fungi isolated from plant litter in freshwater ecosystems of Korea

( Jaeduk Goh ),( Hye Yeon Mun ),( Yu-jeong Jeon ),( Namil Chung ),( Young-hwan Park ),( Sangkyu Park ),( Hyejin Hwang ),( Wonsu Cheon ) 한국균학회 2020 韓國菌學會誌 Vol.48 No.2

Freshwater ecosystems provide a complex environment for microorganisms. In this study, we isolated diverse fungal strains from plant litter in freshwaters. These strains were identified using molecular phylogenetic analyses of rDNA and/or other gene sequences (TUB, GAPDH, and EF1 ). In addition, we examined their morphological characteristics by microscopy and cultural characteristics on several media. We identified six previously unrecorded Sordariomycetes species in Korea, i.e., Colletotrichum godetiae, Discosia rubi, Robillarda sessilis , Monochaetia dimorphospora , Idriella lunata , and Phialemoniopsis endophytica . Of these, D. rubi and M. dimorphospora exhibited high extracellular amylase, lipase, and protease activities, suggesting that these fungal isolates might play an important role as decomposers in freshwater ecosystems. Plant litter could thus be a good source for isolating and investigating previously undocumented fungal species in freshwater environments.

Isolation and Characterization of Previously Undescribed Seventeen Fungal Species Belonging to the order Hypocreales in Korea

Goh Jaeduk,Oh Yoosun,Park Young-Hwan,Mun Hye Yeon,Park Sangkyu,Cheon Wonsu 한국균학회 2022 韓國菌學會誌 Vol.50 No.1

Hypocreales is one of the largest orders within the class Sordariomycetes in Ascomycota. Several species of this order are cosmopolitan and have a broad range of habitats. Here, we isolated several fungal strains from environmental samples, including freshwater sediment and plant litter. The strains were identified via molecular and phylogenetic analyses of rDNA and other DNA markers, such as TUB , RPB2 , and EF1 . The morphological characteristics of the fungi were investigated using microscopy, and culture characteristics were assessed from their growth on several media. We identified 17 species previously unrecorded in Korea: Dactylonectria hordeicola, Flavocillium bifurcatum, Fusarium luffae, Ilyonectria ilicicola, Ilyonectria qitaiheensis, Ilyonectria robusta, Lecanicillium aphanocladii, Nectria ulmicola, Neonectria lugdunensis, Ovicillium oosporum, Pseudonectria foliicola, Sarocladium spinificis, Scolecofusarium ciliatum, Trichoderma appalachiense, Trichoderma subviride, Trichoderma taiwanense, and Trichoderma tsugarense. Hypocreales is one of the largest orders within the class Sordariomycetes in Ascomycota. Several species of this order are cosmopolitan and have a broad range of habitats. Here, we isolated several fungal strains from environmental samples, including freshwater sediment and plant litter. The strains were identified via molecular and phylogenetic analyses of rDNA and other DNA markers, such as , , and . The morphological characteristics of the fungi were investigated using microscopy, and culture characteristics were assessed from their growth on several media. We identified 17 species previously unrecorded in Korea: Dactylonectria hordeicola, Flavocillium bifurcatum, Fusarium luffae, Ilyonectria ilicicola, Ilyonectria qitaiheensis, Ilyonectria robusta, Lecanicillium aphanocladii, Nectria ulmicola, Neonectria lugdunensis, Ovicillium oosporum, Pseudonectria foliicola, Sarocladium spinificis, Scolecofusarium ciliatum, Trichoderma appalachiense, Trichoderma subviride, Trichoderma taiwanense, and Trichoderma tsugarense.

Four Species of Montagnulaceae Unrecorded in Korea and Isolated from Plant Litter in Freshwater

( Jaeduk Goh ),( Hye Yeon Mun ),( Yoosun Oh ),( Namil Chung ) 한국균학회 2016 韓國菌學會誌 Vol.44 No.4

Freshwater is a diverse and complex environment for fungi and provides several types of habitat including plant litter, sediment, and carcasses. We collected plant litter from the main stream and branch streams of Nakdong River, Sohancheon in Samcheok, and Geumoreum in Jeju. From several samples of plant litter, we isolated 8 fungal strains belonging to 4 Montagnulaceae species unrecorded in Korea: Paraconiothyrium archidendri, Paraphaeosphaeria sporulosa, Paraphaeosphaeria michotii, and Paraphaeosphaeria viridescens. These fungi were identified by phylogenetic analysis using the internal transcribed spacer (ITS) region and examination of morphological characteristics. Montagnulaceae is known as one of the families in Pleosporales and includes coniothyrium-like fungi. In this study, we described phylogenetic analysis and mycological characteristics of these species, and this is the first report of these taxa in Korea.

Seven Previously Unrecorded Fungal Species Isolated from Freshwater Ecosystems in Korea

( Jaeduk Goh ),( Hye Yeon Mun ),( Yoosun Oh ) 한국균학회 2021 韓國菌學會誌 Vol.49 No.2

Various freshwater ecosystems, such as streams, lakes and rivers, provide a dynamic habitat for fungi. In this study, we isolated several fungal strains from freshwater sediment and plant litter. The strains were identified using molecular phylogenetic analyses of rDNA and beta tubulin (TUB) sequences. Morphological characteristics of the fungi were also investigated using microscopy and culture characteristics of the fungi grown on several media. We identified seven species previously unrecorded in Korea, Nothophoma spiraeae, Westerdykella aquatica, W. aurantiaca, W. dispersa, Chrysosporium sanyaense, C.pseudomerdarium and Taeniolella phialosperma.

First Report of Six Trichoderma Species Isolated from Freshwater Environment in Korea

( Jaeduk Goh ),( Bora Nam ),( Jae Sung Lee ),( Hye Yeon Mun ),( Yoosun Oh ),( Hyang Burm Lee ),( Namil Chung ),( Young-joon Choi ) 한국균학회 2018 韓國菌學會誌 Vol.46 No.3

Trichoderma (Hypocreaceae) is one of the most ubiquitous genera worldwide. This genus has an excellent ability to adapt to diverse environments, even under poor nutritional conditions, such as in freshwater. However, little is known about the diversity of Trichoderma species in freshwater environments. In this study, we isolated diverse fungal strains from algae, plant litter, and soil sediment in streams in Korea. The strains were identified based on molecular phylogenetic analyses of internal transcribed spacer (ITS) rDNA and translation elongation factor 1 (TEF1α) sequences. We also investigated their morphological characteristics by microscopic observation and determination of cultural features on different media. As a result, six Trichoderma species were found in Korea: T. afroharzianum, T. capillare, T. guizhouense, T. paraviridescens, T. reesei, and T. saturnisporum. Interestingly, T. paraviridescens showed both cellulose activity and hypoxia stress tolerance phenotypes, indicating its role as a decomposer in freshwater ecosystems. Our study revealed that freshwater environment could be a good candidate for investigating the species diversity of Trichoderma.

Isolation and Characterization of Eleven Unrecorded Pezizomycotina Species from Freshwater Ecosystems in Korea

( Jaeduk Goh ),( Yu-jeong Jeon ),( Hye Yeon Mun ),( Namil Chung ),( Young-hwan Park ),( Sangkyu Park ),( Hyejin Hwang ),( Wonsu Cheon ) 한국균학회 2020 韓國菌學會誌 Vol.48 No.4

Freshwater fungi are a poly-phylogenetic group of taxonomically diverse organisms. In this study, we isolated diverse fungal strains from various environmental samples obtained from freshwaters in Korea. These strains were identified by performing molecular phylogenetic analyses of rDNA and/or other sequences (beta-tubulin, RNA polymerase II, and translation elongation factor 1). In addition, we examined their morphological characteristics microscopically and cultural characteristics using different media. We identified eleven unrecorded Pezizomycotina species: Cladosporium angulosum , Pseudorobillarda phragmitis, Paraconiothyrium estuarinum, Pseudopithomyces palmicola, Pyrenochaetopsis paucisetosa, Thelebolus globosus, Plagiostoma mejianum, Trichoderma cremeum, Fusarium tanahbumbuense , Coniochaeta endophytica , and Chaetomium tenue . Environmental samples obtained from different freshwater ecosystems in Korea could thus be a good source for isolating and investigating novel fungal species.

First Reports of Unrecorded Mortierellomycetes and Umbelopsidomycetes Fungi from Freshwater Ecosystems in Korea

Jaeduk Goh,Yoosun Oh,Hye Yeon Mun 한국균학회 2023 韓國菌學會誌 Vol.51 No.3

In this study, we isolated several fungal strains from filtered water and sediment collectedfrom rivers and streams. The strains were identified by molecular phylogenetic analyses ofrDNA sequences (internal transcribed spacer [ITS], large subunit of ribosomal DNA [LSU]). The morphological characteristics of the fungi were investigated using microscopy, and theculture characteristics of fungi grown on several media were examined. We identified fourspecies previously unknown in South Korea, namely, Dissophora globulifera, Linnemanniaexigua, Mortierella rishikesha and Umbelopsis autotrophica.

Evaluation of Sequential Planting Method for Screening of Durable Resistance against Rice Blast in Rice Breeding Program

Goh, Jaeduk,Kim, Byoung-Ryun,Shin, Dong Bum,Kang, In Jeong,Lee, Bong Choon,Kang, Hang-Won,Han, Seong-Sook The Korean Society of Plant Pathology 2015 식물병연구 Vol.21 No.1

A sequential planting method was developed to screen rice plants with durable resistance against rice blast in a short time, and applied for several years in Korean rice breeding program. In this study, we showed the advantages of a sequential planting method compared to other pathogenicity tests. The correlation analysis among three pathogenicity tests and other factors demonstrated that durable resistance depended on the average of diseased leaf area and the number of compatible pathogens. Significant correlations were found in the nursery test but not in the field test result. In addition, we traced changes in the pathogen population during sequential planting stages through re-isolation of the pathogen. The portion of compatible pathogens was increased during sequential planting. Through this study, we provide an effective sequential planting method and direction of durable resistance in a breeding program.

A putative MAP kinase kinase kinase, MCK1, is required for cell wall integrity and pathogenicity of the rice blast fungus, Magnaporthe oryzae.

Jeon, Junhyun,Goh, Jaeduk,Yoo, Sungyong,Chi, Myoung-Hwan,Choi, Jaehyuk,Rho, Hee-Sool,Park, Jongsun,Han, Seong-Sook,Kim, Byeong Ryun,Park, Sook-Young,Kim, Soonok,Lee, Yong-Hwan APS Press 2008 Molecular plant-microbe interactions Vol.21 No.5

<P>Insertional mutagenesis of Magnaporthe oryzae led to the identification of MCK1, a pathogenicity gene predicted to encode mitogen-activated protein kinase kinase kinase (MAPKKK) homologous to BCK1 in Saccharomyces cerevisiae. Targeted disruption of MCK1 resulted in the fungus undergoing autolysis and showing hypersensitivity to cell-wall-degrading enzyme. The mck1 produced significantly reduced numbers of conidia and developed appressoria in a slightly retarded manner compared with the wild type. Appressorium of the mck1 mutant was unable to penetrate into plant tissues, thereby rendering the mutant nonpathogenic. Cytorrhysis assay and monitoring of lipid mobilization suggested that the appressorial wall was altered, presumably affecting the level of turgor pressure within appressorium. Furthermore, the mck1 mutant failed to grow inside plant tissue. Complementation of the mutated gene restored its ability to cause disease symptoms, demonstrating that MCK1 is required for fungal pathogenicity. Taken together, our results suggest that MCK1 is an MAPKKK involved in maintaining cell wall integrity of M. oryzae, and that remodeling of the cell wall in response to host environments is essential for fungal pathogenesis.</P>

Comparative Pathogenicity and Host Ranges of Magnaporthe oryzae and Related Species

Hyunjung Chung,Jaeduk Goh,Seong-Sook Han,Jae-Hwan Roh,Yangseon Kim,Sunggi Heu,Hyeong-Kwon Shim,Da Gyeong Jeong,In Jeong Kang,Jung-Wook Yang 한국식물병리학회 2020 Plant Pathology Journal Vol.36 No.4

Host shifting and host expansion of fungal plant pathogens increases the rate of emergence of new pathogens and the incidence of disease in various crops, which threaten global food security. Magnaporthe species cause serious disease in rice, namely rice blast disease, as well as in many alternative hosts, including wheat, barley, and millet. A severe outbreak of wheat blast due to Magnaporthe oryzae occurred recently in Bangladesh, after the fungus was introduced from South America, causing great loss of yield. This outbreak of wheat blast is of growing concern, because it might spread to adjacent wheat-producing areas. Therefore, it is important to understand the host range and population structure of M. oryzae and related species for determining the evolutionary relationships among Magnaporthe species and for managing blast disease in the field. Here, we collected isolates of M. oryzae and related species from various Poaceae species, including crops and weeds surrounding rice fields, in Korea and determined their phylogenetic relationships and host species specificity. Internal transcribed spacer-mediated phylogenetic analysis revealed that M. oryzae and related species are classified into four groups primarily including isolates from rice, crabgrass, millet and tall fescue. Based on pathogenicity assays, M. oryzae and related species can infect different Poaceae hosts and move among hosts, suggesting the potential for host shifting and host ex- pansion in nature. These results provide important information on the diversification of M. oryzae and re- lated species with a broad range of Poaceae as hosts in crop fields.