• 한국자원식물학회지
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• 제22권6호
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• pp.571-583
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• 2009

Lam Dong Province of Vietnam has an exceptional diversity of orchids and herbs. At least 920 herb species are widely mentioned in Vietnamese traditional medicinal literature and over 239 Lam Dong wild orchid species are used for attention under the Conservation Vietnamese wild orchids projects. In collaboration with Department of Plant Biotechnology, Dongguk University - South Korea working under supported ODA funds from Korea government (MIFAFF), we will consider how to collecting and preserving these plants in situ or conservating in vitro as a genetic resource.

• The Plant Pathology Journal
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• 제26권2호
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• pp.194-197
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• 2010

Most orchids are propagated by tissue culture. To survey the viral infection of tissue cultured Orchids, total RNA was extracted from in vitro Cymbridium and Phalaenopsis spp. collected from companies producing tissue-cultured orchids, and RT-PCR analysis was conducted with primer pairs specific to Cymbidium mosaic virus (CymMV) and Odontoglossum ring spot virus(ORSV), which are infecting wide range of orchid genera. The bulb size of Cymbidium infected with CymMV and ORSV was compared with healthy one at 10 months after planting in vitro orchids in the glasshouse. The CymMV or ORSV infection in 97 Cymbidium and 55 Phalaenopsis plants was 84.5 and 89.1 %, respectively. Mixed infection was found in 52.6 and 47.3% of Cymbidium and Phalaenopsis tested, whereas virus-free orchids were 15.5 and 10.9%, respectively. The CymMV and ORSV reduced the bulb size by 2.7-50% depending on the cultivars of Cymbidium. The both viruses caused yellowing, mottle and mosaic with or without necrosis in 4 Cymbidium cultivars.

• 한국식물병리학회지
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• 제14권5호
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• pp.536-542
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• 1998

Ten isolates of the orchid mycorrhizal fungi were isolated from the roots of Korean native orchid plants (Cymbidium goeringii) which inhabitate mainly in southern and western areas of Korea. The growth rates and color of the isolates in potato dextrose agar (PDA) were various. Microscopic observations of the hyphae isolated were identified as Rhizoctonia repens and R. endophytica var endophytica or their related species. R. repens was isolated from the roots of the Korean native orchids, but R. endophytica var endophyica was only isolated from the roots of the commercial orchids introduced from foreign countries. Also, the polymorephic patterns of genomic DNA extracted from selected isolates were compared with those of DNA extracted from the orchid mycorrhizal fungi isolated previously and similar band patterns were observed among those isolates. Five isolates of R. repens were selected and cultured at the oatmeal agar for investigating their symbiosis with orchid plants. The symbiotic specificity between orchid plants and isolated orchid mycorrhizal fungi was observe by growing orchids about six months in the greenhouse. The symbiotic responses of the commercial orchid plants with selected isolates were quite different form different isolates due to the genetic variations.

• Mycobiology
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• 제28권1호
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• pp.17-26
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• 2000

The orchid symbiotic fungi were isolated from the roots of Korean native orchid (Cymbidium goeringii) collected and Chinese orchid (C. sinense) obtained from greenhouses. They were identified as a species of Rhizoctonia, based on the sequences of 18r rDNA, the microscopic observations of mycelia, and the symbiotic relationships with commercial orchids. The isolate collected from Chinese orchids was revealed to be a species of Ceratobasidium endophytica, and to be different from the other isolates at the thickness of the mycelia stained in the root cells of Korean native orchids. The other isolates collected from the Korean native orchids were considered to be a species of Tulsanella repens (anamorphic: Epulorhiza repens) or its related one. The physiologic or microscopic variations were oftenly observed among them, but the tendency of grouping these in the 18s rDNA sequences were observed to be consistent with those of the localities collected. The further taxonomical segregating for Korean symbiotic fungi was not made because the information concerned were limited in this moment, but was recognized as based on the sequences of 18s DNA.

• 한국식물병리학회지
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• 제14권2호
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• pp.130-135
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• 1998

This study was carried out to detect cymbidium mosaic potexvirus (CymMV) and odontoglossum ringspot tobamovirus (ORSV) in cultivated orchid plants in Korea. The standard double antibody sandwich enzyme-linked immunosorbent assay (ELISA) and reverse transcription polymerase chain reaction (RT-PCR) were carried out for detection of the viruses in the collected orchid samples. ELISA was suitable for massive-scale diagnostic method for virus detection in orchids. RT-PCR was rapid, time-saving and reliable detective method, and detection limit data showed that RT-PCR was 103 times more sensitive than ELISA. Of the 321 individual orchids representing 5 orchids genera tested by the ELISA, CymMV and ORSV were detected in 15.6% and 22.4%, and mixed infection of the both viruses with 4.9%, respectively. Of the Cymbidium plants tested, cultivated plants showed 52.5% virus infection rate with either CymMV or ORSV and both viruses.

• 한국균학회지
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• 제39권1호
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• pp.7-10
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• 2011

울릉도에서 채집된 6종의 지생란의 뿌리에서 난균근균을 확인하였다. 난균근균의 감염이 확인되었다. 각 종의 뿌리로 부터 분리된 난균근균이 분자적인 분석을 통하여 확인되였다. 뿌리로부터 분리된 균에서 DNA를 추출하여, 담자균류에 특이적인 프라이머인 ITS1-OF와 ITS4-OF를 사용하여 ITS 지역을 증폭한 후 염기서열을 분석하여 두 식물의 뿌리에 공생하는 난균근균을 동정하였다. 분자적인 분석을 통해 Tulasnellaceae 와 Ceratobasidaceae에 속하는 난균근균이 확인되었다.

• Plant Biotechnology Reports
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• 제3권1호
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• pp.1-56
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• 2009

Orchid seeds are nearly microscopic in size. Because of that, many fanciful theories were proposed for the origin of orchids. Almost 400 years separate the time when orchid seeds were seen for the first time and the development of a practical asymbiotic method for their germination. The seeds were first observed and drawn during the sixteenth century. Seedlings were first described and illustrated in 1804. The association between orchid and fungi was observed as early as 1824, while the requirement for mycorrhiza for seed germination was established in 1899. An asymbiotic method for orchid seed germination was developed in 1921. After Knudson's media B and C were formulated, orchids growing and hybridization became widespread. Hybrids which early growers may not have even imagined became possible.

• Mycobiology
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• 제40권4호
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• pp.263-264
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• 2012

Sclerotium rot was found on Cymbidium orchids at Seosan-si, Chungcheongnam-do, Korea, in July, 2010. Symptoms occurred on low leaves, which turned yellowish, after which the entire plant wilted. Severely infected plants were blighted and eventually died. White mycelial mats and sclerotia appeared on pseudobulbs. Based on the mycological characteristics and pathogenicity, the causal fungus was identified as Sclerotium rolfsii. This is the first report of new Sclerotium rot on Cymbidium spp. caused by S. rolfsii in Korea.

• Mycobiology
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• 제48권4호
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• pp.321-325
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• 2020

A Colletotrichum species was isolated from leaves of Cymbidium exhibiting symptoms of anthracnose. In this study, the isolates obtained were identified based on recent taxonomic approaches for the genus Colletotrichum. The identity of the causal pathogen was confirmed using morphological data and phylogenetic analysis of combined multi-gene dataset (internal transcribed spacer, glyceraldehyde 3-phosphate dehydrogenase, chitin synthase-1, actin, histone3, beta-tubulin, and calmodulin). Pathogenicity testing revealed that the isolates were pathogenic to Cymbidium. Based on these results, the fungal pathogen occurring on Cymbidium orchids was identified as Colletotrichum cymbidiicola, which is a newly recorded species in Korea.

• 한국식물병리학회지
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• 제12권4호
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• pp.455-458
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• 1996

난 탄저병균의 배양적 특성과 탄저병의 발생 특성을 조사하였다. 자연 발병한 양란과 호접란의 잎에는 초기에 암갈색 또는 검은색의 둥글고 작은 반점이 형성되어 점차 진전되면서 검게타고 병이 진전됨에 따라 잎전체가 고사하고 심할 경우 줄기와 식물체 전체가 고사하였다. 탄저병에 감염된 양란과 호접란의 병환부로부터 분리된 Colletotrichum gloeosporioides는 상처접종에 의해서만 각각 양란과 호접란 병원성을 나타내었고, 덴파레 및 춘란에 대해서도 모두 병원성을 나타내었다. 양란은 상위엽일수록 탄저병균에 대해 감수성을 나타내었으며, 호접란이 탄저병균에 대해 감수성을 나타낸 반면에 춘란이 가장 저항성을 나타내었으며 양란과 덴파레는 중도 반응을 보였다. 탄저병균의 균사생장과 분생포자형성 적온은 각각 $25^{\circ}C$였으며, 베노밀 수화제와 비타놀 수화제에 대하여 감수성을 나타내었다.