• Journal of Microbiology and Biotechnology
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• 제31권11호
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• pp.1526-1532
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• 2021

Suaeda australis, Phragmites australis, Suaeda maritima, Suaeda glauca Bunge, and Limonium tetragonum in the Seocheon salt marsh on the west coast of the Korean Penincula were sampled in order to identify the endophytes inhabiting the roots. A total of 128 endophytic fungal isolates belonging to 31 different genera were identified using the fungal internal transcribed spacer (ITS) regions and the 5.8S ribosomal RNA gene. Fusarium, Paraconiothyrium and Alternaria were the most commonly isolated genera in the plant root samples. Various diversity indicators were used to assess the diversity of the isolated fungi. Pure cultures containing each of the 128 endophytic fungi, respectively, were tested for the plant growth-promoting abilities of the fungus on Waito-C rice germinals. The culture filtrate of the isolate Lt-1-3-3 significantly increased the growth of shoots compared to the shoots treated with the control. Lt-1-3-3 culture filtrate was analyzed and showed the presence of gibberellins (GA₁ 2.487 ng/ml, GA₃ 2.592 ng/ml, GA₉ 3.998, and GA₂₄ 6.191 ng/ml). The culture filtrate from the Lt-1-3-3 fungal isolate produced greater amounts of GA₉ and GA₂₄ than the wild-type Gibberella fujikuroi, a fungus known to produce large amounts of gibberellins. By the molecular analysis, fungal isolate Lt-1-3-3 was identified as Gibberella intermedia, with 100% similarity.

• The Plant Pathology Journal
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• 제39권4호
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• pp.397-408
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• 2023

Fire blight disease, caused by Erwinia amylovora, is a devastating affliction in apple cultivation worldwide. Chemical pesticides have exhibited limited effectiveness in controlling the disease, and biological control options for treating fruit trees are limited. Therefore, a relatively large-scale survey is necessary to develop microbial agents for apple trees. Here we collected healthy apple trees from across the country to identify common and core bacterial taxa. We analyzed the endophytic bacterial communities in leaves and twigs and discovered that the twig bacterial communities were more conserved than those in the leaves, regardless of the origin of the sample. This finding indicates that specific endophytic taxa are consistently present in healthy apple trees and may be involved in vital functions such as disease prevention and growth. Furthermore, we compared the community metabolite pathway expression rates of these endophyte communities with those of E. amylovora infected apple trees and discovered that the endophyte communities in healthy apple trees not only had similar community structures but also similar metabolite pathway expression rates. Additionally, Pseudomonas and Methylobacterium-Methylorobrum were the dominant taxa in all healthy apple trees. Our findings provide valuable insights into the potential roles of endophytes in healthy apple trees and inform the development of strategies for enhancing apple growth and resilience. Moreover, the similarity in cluster structure and pathway analysis between healthy orchards was mutually reinforcing, demonstrating the power of microbiome analysis as a tool for identifying factors that contribute to plant health.

• 한국균학회지
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• 제45권3호
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• pp.229-233
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• 2017

본 연구에서는 민주지산에 서식하는 철쭉(Rhododendron schlippenbachii)의 뿌리에서 내생균을 분리하였다. 형태적 특성의 확인 및 ribosomal DNA의 internal transcribed spacer(ITS) 지역, large subunit (LSU)지역의 분자적 분석을 통해 국내 미기록종인 Engyodontium album, Phaeosphaeria microscopica 2종을 동정하였다. 연구 과정에서 확인된 미기록종 내생균 2종의 형태적, 분자적 특성을 여기에 기술하였다.

• Mycobiology
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• 제35권4호
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• pp.186-190
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• 2007

This study was conducted to investigate the effects of foliar endophytic fungi and arbuscular mycorrhizal fungi (AMF) on plant community structure in experimental microcosms containing an assemblage of five species of plants (Oenothera odorata, Plantago asiatica, Trifolium repens, Isodon japonicas and Aster yomena). Leaves of Sasa borealis, Potentilia fragarioides, and Viola mandshurica were collected in Chungbuk, Korea. Endophytic fungi were isolated from the surface sterilized leaves and identified to species level using molecular and morphological techniques. Four isolates of the endophytic fungi were inoculated to the leaves of host plants in the microcosms. Also, three species of AMF spores were extracted from pure cultures and the mixture of the three species inoculated to the roots of the plants. After four months of growth in a green house, effects of both symbiotic fungi on plant species diversity, community composition and productivity were examined. The plant species diversity showed significant differences with inoculation of the symbiotic fungi. Results indicate that AMF significantly affect plant productivity and plant community structure.

• Mycobiology
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• 제36권4호
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• pp.222-227
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• 2008

Upon studying the diversity of fungal endophytes associated with pine trees in Korea, many species of Penicillium were encountered. In this study, we report two species of Penicillium isolated from the needles of Pinus rigida. Based on ID region analysis, cultural and morphological characteristics, the two species were identified as Penicillium fellutanum and P. toxicarium, both of which are new to Korea.

• Mycobiology
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• 제39권3호
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• pp.151-157
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• 2011

The endophytic fungal populations of different tissues of Taxus baccata grown at high altitudes in West Bengal, India were explored. These isolated fungal populations represented different genera, which were screened for taxol production using immunoassay technique. The culture AAT-TS-$4_1$ that produced taxol was identified as Gliocladium sp. based on its cultural, morphological characteristics, internal transcribed spacer, and 18S rRNA sequence analysis. Kinetics of taxol production as a function of culture growth were investigated.

• 한국균학회소식:학술대회논문집
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• 한국균학회 2018년도 춘계학술대회 및 임시총회
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• pp.49-49
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• 2018

A variety of bioactive secondary metabolites have been reported from plant-associated microorganisms. Halophytes, plants that can only grow in hypersaline area, were reported to host beneficial microorganisms such as plant growth-promoting endophytes. The microorganisms have been reported to show notable mutualistic symbiosis with halophytes to help them survive in high saline condition. Finding out bioactive secondary metabolites as well as elucidation of relationship(s) between microbes and the host halophyte has been paid attention, because of their functional diversity. Novel microbes often have associated with novel natural products. In an effort to investigate natural compounds with interesting structures from fungi, we selected plants from a distinct environmental setting which could be a promising source. Several fungi were isolated from halophyte or medicinal plants. Some strains of the fungi were cultivated on a large scale and extracted with ethyl acetate, which were subjected to a series of chromatographic methods, leading to the isolation of tens of compounds. The isolated compounds were identified by analysis of spectroscopic methods such as 1D-, 2D-NMR, and MS. Details of isolation, structure determination, and biological activities will be discussed.

• Journal of Plant Biology
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• 제36권2호
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• pp.177-182
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• 1993

The root nodules of Elaeagnus umbellata were coralloid-shape due to repeated dichotomous branching of nodule meristem. The filamentous endophyte with vesicle cluster ranging from 30 ${\mu}{\textrm}{m}$ to 60 ${\mu}{\textrm}{m}$ in diameter was present only in the cortical cells. The isolated endophytes in vitro culture showed typical Frankia morphology, consisting of highly branched hyphae ranging from 0.8 ${\mu}{\textrm}{m}$ to 1.0 ${\mu}{\textrm}{m}$ in diameter, terminal and intrahyphal sporangia varing in shape and size up to 60 ${\mu}{\textrm}{m}$ in length and laminated vesicles. Its infectivity and effectivity were confirmed by induction of nitrogen-fixing root nodules on the inoculated seedlings of two Elaeagnus species. Consequently, the isolate was confirmed as a true symbiont of Elaeagnus umbellata root nodule and named Frankia EuIK1.

• Mycobiology
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• 제41권2호
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• pp.82-85
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• 2013

The needled leaves of three conifer species were collected in Mt. Taehwa during different seasons of the year. Total 59 isolates and 19 species of endophytic fungi were isolated from the leaves and identified using morphological and molecular characteristics. As a result, Shannon index was different in its host plant; Larix kaempferi had a highest value of species diversity. According to the sampling season, 9 species of 19 species were isolated during fall season. The results suggest that the existing of host plant and sampling season are major factors of distribution of endophytic fungi.

• 한국균학회지
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• 제48권2호
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• pp.117-124
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• 2020

In this study, we isolated endophytic fungi from the conifer leaves of Pinus densiflora inhabiting Mt. Gyehwasan in Korea. We identified the isolated fungal strains based on their morphological characteristics and phylogenetic analysis using DNA sequences of the internal transcribed spacer, small subunit rDNA, large subunit rDNA, and β-tubulin region. In the process of this study, we confirmed two endophytic fungi that have not been recorded previously in Korea, Lophiostoma macrostomum and Pestalotiopsis lespedezae. In this report, we described the morphological characteristics of these fungal strains and the results of their molecular analysis.