• 한국임상수의학회지
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• 제25권3호
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• pp.207-210
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• 2008

Trichophyton erinacei is a dermatophyte pathogen that infects both humans and hedgehogs. A two-month old female four-toed hedgehog presented to the Chonbuk Animal Medical Center with pruritus, excoriation and crust on her face for ten days. The owner of the hedgehog also exhibited the clinical signs of scaly erythema with fine vesicles on her neck. A presumptive diagnosis of dermatophytosis was made based on the results of an acetate tape preparation in which hyphae and chains of arthroconidia were observed. The crusts from the lesions were then cultured on Sabouraud Dextrose Agar for identification. After 10 days of incubation, downy colored colonies that had a central umbo with a white granular surface and a yellow pigment ring in the reverse were observed. Microscopic analysis revealed the presence of numerous teardrop shaped microconidia singly attached to the sides of the hyphae. In addition, 2-6 roomed macroconidia that were somewhat irregular in shape and size were present, and abundant intermediate sized spores were observed between the micro and macro conidia. To confirm that the culture was T. erinacei, the internal transcribed spacer region of the 5.8S phase of the ribosomal RNA gene (ITS1-5.8S-ITS2 rDNA) was amplified by PCR and then sequenced. A 679-base pair fragment of DNA was then compared with sequences in GenBank and found to be 99% homologous with sequences of T. erinacei (Z97997 and Z97996. The clinical signs were resolved after four weeks of treatment with oral and topical ketoconazole and chlorhexidine. To the best of our knowledge, this represents the first case of T. erinacei isolated from a four-toed hedgehog in Korea.

• 식물병연구
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• 제19권3호
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• pp.229-232
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• 2013

경상남도농업기술원 시험포장에서 S. rolfsii에 의한 오이 흰비단병 증상이 발생하였다. 전형적인 병징으로 시들음, 썩음, 줄기와 과실 수침상을 보였고 감염된 식물체는 결국 시들어 말라 죽었다. 병반부와 토양 표면에 흰색의 곰팡이가 발생하며 갈색의 작고 둥근 균핵이 형성되었다. 감자한천배지에서 균총은 흰색이고 잘 자라며 배양기간이 경과됨에 따라 갈색의 작은 둥근 균핵을 많이 형성하였다. 균핵의 크기는 1-3 mm이며 균사의 폭은 4-8 ${\mu}m$였다. 균사생육과 균핵 형성 적온은 $30^{\circ}C$이었다. 주사전자현미경 검경결과 균사 특유의 clamp connection이 관찰되었다. 코흐의 가설을 만족하기 위해, 50일간 키운 오이 유묘를 이용하여 병원성 검정을 실시한 결과 흰비단병 특유의 병징을 유도하였다. 오이에서 발생한 병징과 병원균의 균학적 특징, 그리고 ITS rDNA 염기서열 비교분석 결과, 이 병을 Sclerotium rolfsii Saccardo에 의한 오이 흰비단병으로 명명하고자 제안한다.

• 식물병연구
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• 제23권1호
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• pp.56-59
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• 2017

2011년부터 2013년까지 예산 지역의 농가포장에서 재배 중인 바질에서 균핵병으로 의심되는 증상이 지속적으로 관찰되었다. 초기에는 잎과 줄기가 갈색으로 변하기 시작하여 반점이 커지면서 점차 위쪽으로 진전, 위조하여 결국 전체적으로 썩어 죽는다. 잎과 줄기의 병반부에는 다량의 흰색 균사가 발생하며 $30-100{\mu}m$ 직경의 균핵이 형성하였다. PDA상에 균체는 흰색과 옅은 초콜릿 흑색으로 다양한 색을 나타내었고, 균핵은 검은색으로 대부분 불규칙한 구형이며 크기는 $5-50{\mu}m$였다. 병원균을 인위적으로 접종한 바질의 잎과 줄기에서는 자연 발생된 바질과 동일한 괴사와 위조증상을 보이며, 병반에서 역시 같은 균을 분리하였다. 이상과 같이 병원균의 균학적 특징, ITS 염기서열 분석, 병원성 검정 결과 본 병해는 Sclerotinia sclerotiorum에 의한 바질균핵병으로 명명할 것을 제안한다.

• Journal of Ecology and Environment
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• 제41권9호
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• pp.271-280
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• 2017

Background: Soil microorganisms play key roles in nutrient cycling and are distributed throughout the soil profile. Currently, there is little information about the characteristics of the microbial communities along the soil depth because most studies focus on microorganisms inhabiting the soil surface. To better understand the functions and composition of microbial communities and the biogeochemical factors that shape them at different soil depths, we analyzed microbial activities and bacterial and fungal community composition in soils up to a 120 cm depth at a fallow field located in central Korea. To examine the vertical difference of microbial activities and community composition, ${\beta}$-1,4-glucosidase, cellobiohydrolase, ${\beta}$-1,4-xylosidase, ${\beta}$-1,4-N-acetylglucosaminidase, and acid phosphatase activities were analyzed and barcoded pyrosequencing of 16S rRNA genes (bacteria) and internal transcribed spacer region (fungi) was conducted. Results: The activity of all the soil enzymes analyzed, along with soil C concentration, declined with soil depth. For example, acid phosphatase activity was $125.9({\pm}5.7({\pm}1SE))$, $30.9({\pm}0.9)$, $15.7({\pm}0.6)$, $6.7({\pm}0.9)$, and $3.3({\pm}0.3)nmol\;g^{-1}\;h^{-1}$ at 0-15, 15-30, 30-60, 60-90, and 90-120 cm soil depths, respectively. Among the bacterial groups, the abundance of Proteobacteria (38.5, 23.2, 23.3, 26.1, and 17.5% at 0-15, 15-30, 30-60, 60-90, and 90-120 cm soil depths, respectively) and Firmicutes (12.8, 11.3, 8.6, 4.3, and 0.4% at 0-15, 15-30, 30-60, 60-90, and 90-120 cm soil depths, respectively) decreased with soil depth. On the other hand, the abundance of Ascomycota (51.2, 48.6, 65.7, 46.1, and 45.7% at 15, 30, 60, 90, and 120 cm depths, respectively), a dominant fungal group at this site, showed no clear trend along the soil profile. Conclusions: Our results show that soil C availability can determine soil enzyme activity at different soil depths and that bacterial communities have a clear trend along the soil depth at this study site. These metagenomics studies, along with other studies on microbial functions, are expected to enhance our understanding on the complexity of soil microbial communities and their relationship with biogeochemical factors.

• ALGAE
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• 제29권2호
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• pp.75-99
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• 2014

A small dinoflagellate, Ansanella granifera gen. et sp. nov., was isolated from estuarine and marine waters, and examined by light microscopy, scanning electron microscopy, and transmission electron microscopy. In addition, the identity of the sequences (3,663-bp product) of the small subunit (SSU), internal transcribed spacer (ITS) region (ITS1, 5.8S, ITS2), and D1-D3 large subunit (LSU) rDNA were determined. This newly isolated, thin-walled dinoflagellate has a type E eyespot and a single elongated apical vesicle, and it is closely related to species belonging to the family Suessiaceae. A. granifera has 10-14 horizontal rows of amphiesmal vesicles, comparable to Biecheleria spp. and Biecheleriopsis adriatica, but greater in number than in other species of the family Suessiaceae. Unlike Biecheleria spp. and B. adriatica, A. granifera has grana-like thylakoids. Further, A. granifera lacks a nuclear fibrous connective, which is present in B. adriatica. B. adriatica and A. granifera also show a morphological difference in the shape of the margin of the cingulum. In A. granifera, the cingular margin formed a zigzag line, and in B. adriatica a straight line, especially on the dorsal side of the cell. The episome is conical with a round apex, whereas the hyposome is trapezoidal. Cells growing photosynthetically are $10.0-15.0{\mu}m$ long and $8.5-12.4{\mu}m$ wide. The cingulum is descending, the two ends displaced about its own width. Cells of A. granifera contain 5-8 peripheral chloroplasts, stalked pyrenoids, and a pusule system, but lack nuclear envelope chambers, a nuclear fibrous connective, lamellar body, rhizocysts, and a peduncle. The main accessory pigment is peridinin. The SSU, ITS regions, and D1-D3 LSU rDNA sequences differ by 1.2-7.4%, >8.8%, and >2.5%, respectively, from those of the other known genera in the order Suessiales. Moreover, the SSU rDNA sequence differed by 1-2% from that of the three most closely related species, Polarella glacialis, Pelagodinium bei, and Protodinium simplex. In addition, the ITS1-5.8S-ITS2 rDNA sequence differed by 16-19% from that of the three most closely related species, Gymnodinium corii, Pr. simplex, and Pel. bei, and the LSU rDNA sequence differed by 3-4% from that of the three most closely related species, Protodinium sp. CCMP419, B. adriatica, and Gymnodinium sp. CCMP425. A. granifera had a 51-base pair fragment in domain D2 of the large subunit of ribosomal DNA, which is absent in the genus Biecheleria. In the phylogenetic tree based on the SSU and LSU sequences, A. granifera is located in the large clade of the family Suessiaceae, but it forms an independent clade.