• The Korean Journal of Mycology
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• v.39 no.1
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• pp.11-15
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• 2011

To provide basic information for Verticillium spp., molecular methods were applied to analyze genetic characteristics within Verticillium spp. including Verticillium dahliae, isolated from diseased plants in two regions of Korea. Five Korean isolates of V. dahliae causing Verticillium wilt on chrysanthemum were analyzed, together with six other Verticillium spp., using mitochondrial small subunit rRNA gene (rns) sequence and random-amplified polymorphic DNA (RAPD). In a phylogenetic tree based on rns region sequences, Korean V. dahliae isolates formed a single clade with foreign isolates, whereas the other Verticillium spp. formed separate groups. In addition to rns sequence analysis, a dendrogram based on RAPD fragment patterns also showed clustering of all V. dahliae isolates into one group, separate from the six different Verticillium spp., and the V. dahliae isolates formed three subgroups which corresponded to the regions of origin, Kumi, Busan city and Canada. This indicates that high genetic variation exists between regions, although the fungus was isolated from the same host plant, chrysanthemum. These results provide the foundation for the study of genetic diversity and relationships among V. dahliae isolates in Korea.

• The Plant Pathology Journal
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• v.17 no.4
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• pp.222-226
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• 2001

In 1997, 103 isolates of Verticillium were obtained from roots and stems of tomato plants showing wilt symptoms in greenhouses in eight areas of Korea. Out of these isolates, 75 were edintified as V. dahliae while 28 were identified as V. albo-atrum based on their morpho-logical and cultural characteristics. Both Verticillium species produced colonies with conidiophores, which were more or less erect, hyaline, with verticillate branches, and with 3-4 phialides at each node. V. dahliae produced microsclerotia, while V. albo-atrum produced resting dark mycelium. Optimum temperatures for mycelial growth of V. dahliae and V. albo-atrum on PDA were 22 and $26^{\circ}$, respectively. Mycelial growth of V. albo-atrum was slower than that of V. dahliae. Pathoge-nicity tests revealed that tomato cvs. Zuikoh No. 102, Kyoryokubeiju No. 2, Zuiken, Kagimuza, and Momotaro were susceptible to V. albo-atrum, while cvs. Zuikoh No. 102 and Kyoryokubeiju No.2 were susceptible to V. dahliae.

• The Korean Journal of Mycology
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• v.47 no.4
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• pp.437-441
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• 2019

Verticillium wilt disease is caused by a fungal plant pathogen Verticillium dahliae, which attacks commercial crops such as chrysanthemum. The conventional methods so far used to identify this fungal pathogen require high expertise and are time-consuming. Therefore, in this study, we developed an assay for the rapid and specific detection of V. dahliae infection using loop-mediated isothermal amplification (LAMP) method. For this assay, four primers for LAMP were designed for targeting cellulose-growth-specific protein partial mRNA gene in Verticillium dahliae. Under standard condition, the optimum reaction temperature for amplification is around 60 ℃ within 60 minutes. This LAMP assay was designed to amplify only present in V. dahliae. When this LAMP assay applied to the DNAs for four other soil-borne fungi and host plants, no amplification was detected. Therefore, this LAMP assay we developed for V. dahliae is expected to do detection at the early stage of its infection. The fast and reliable detection method will allow us to develop effective management system to monitor and control infection of this pathogen in chrysanthemum plant.

• Mycobiology
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• v.46 no.3
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• pp.254-259
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• 2018

Okra (Abelmoschus esculentus (L.) Moench) has gained more popularity as an economically significant plant for its nutritional and medicinal value, especially in China. During 2014-2016, the root disease of okra was discovered in four okra commercial fields surveyed in China. A fungul was isolated from the infected tissues, and was identified by Verticillium dahliae based on morphological characteristics. Pathogenicity test demonstrated that the fungus was pathogenic on okra, and fulfilled Koch's postulates. The analysis of three sequences revealed 99-100% identity with the reported V. dahliae strain in GenBank. Neighbor-joining analysis of the gene sequences revealed that the representative isolates were clustered with V. dahliae. To the best of our knowledge, this is the first report of Verticillium wilt of okra in China.

• Journal of Microbiology and Biotechnology
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• v.24 no.9
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• pp.1149-1161
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• 2014

Cotton plants were sampled and ranked according to their resistance to Verticillium wilt. In total, 642 endophytic fungi isolates representing 27 genera were recovered from Gossypium hirsutum root, stem, and leaf tissues, but were not uniformly distributed. More endophytic fungi appeared in the leaf (391) compared with the root (140) and stem (111) sections. However, no significant difference in the abundance of isolated endophytes was found among resistant cotton varieties. Alternaria exhibited the highest colonization frequency (7.9%), followed by Acremonium (6.6%) and Penicillium (4.8%). Unlike tolerant varieties, resistant and susceptible ones had similar endophytic fungal population compositions. In three Verticillium-wilt-resistant cotton varieties, fungal endophytes from the genus Alternaria were most frequently isolated, followed by Gibberella and Penicillium. The maximum concentration of dominant endophytic fungi was observed in leaf tissues (0.1797). The evenness of stem tissue endophytic communities (0.702) was comparatively more uniform than the other two tissues. Eighty endophytic fungi selected from 27 genera were evaluated for their inhibition activity against highly virulent Verticillium dahliae isolate Vd080 in vitro. Thirty-nine isolates exhibited fungistasis against the pathogen at varying degrees. Seven species, having high growth inhibition rates (${\geq}75%$), exhibited strong antifungal activity against V. dahliae. The antifungal activity of both volatile and nonvolatile metabolites was also investigated. The nonvolatile substances produced by CEF-818 (Penicillium simplicissimum), CEF-325 (Fusarium solani), CEF-714 (Leptosphaeria sp.), and CEF-642 (Talaromyces flavus) completely inhibited V. dahliae growth. These findings deepen our understanding of cotton-endophyte interactions and provide a platform for screening G. hirsutum endophytes with biocontrol potential.

• The Plant Pathology Journal
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• v.40 no.2
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• pp.192-204
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• 2024

In this study, the efficacy of the essential oil of Mentha longifolia, Achillea arabica and Artemisia absinthium plants were evaluated against important soil-borne fungal pathogens as Verticillium dahliae, Rhizoctonia solani, and Fusarium oxysporum. Essential oils were obtained from plants by hydrodistillation method and the chemical components of essential oils were determined by analyzing by gas chromatography-mass spectrometry. The main components found as piperitone oxide (13.61%), piperitenone oxide (15.55%), pulegone (12.47%), 1-menthone (5.75%), and camphor (5.75%) in M. longifolia, á-selinene 13.38%, camphor 13.34%, L-4-terpineneol 8.40%, (-)-á-Elemene 7.01%, 1,8-cineole 4.71%, and (-)-spathulenol 3.84% in A. arabica, and á-thujone (34.64%), 1,8-cineole (19.54%), pulegone (7.86%), camphene (5.31%), sabinene (4.86%), and germacrene-d (3.67%) in A. absinthium. The antifungal activities of the oils were investigated 0.05, 0.1, 0.25, 0.5, 1.00, and 2.00 μl/ml concentrations with the contact effect method. M. longifolia oil (1.00 and 2.00 μl/ml) has displayed remarkable antifungal effect and provided 100% inhibition on mycelial growth of V. dahliae, R. solani and F. oxysporum. The results obtained from this study may contribute to the development of new alternative and safe methods against soil-borne fungal pathogens.

• The Korean Journal of Mycology
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• v.14 no.1
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• pp.89-91
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• 1986

Sixteen seed samples of nine vegetable crops imported from Japan were tested for plant quarantine by routine methods of seed health testing. Nineteen species of fungi including Alternara alternata were identified from the seed samples. Some species were very frequently detected in the seeds. In this experiment, Verticillium albo-atrum, V. dahliae and Macrophomina sp. from the seeds of spinach, and Cercospora capsici, Drechslera hawaiiensis and V. albo-atrum from the seeds of sweet pepper were detected for the first time, respectively. It has been reported that they had a pathogenicity on some vegetable crops in Japan and other countries. The data suggest that an epidemic damage may be occurred if the infected seeds are sown and cultivated in Korea.