• 식물병연구
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• 제13권3호
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• pp.204-206
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• 2007

2006년에서 2007년까지 2년간 자연상태에서 월동후 식물체 부위별 단감 탄저병의 병원균 분리비율을 조사하기 위해 병든 가지의 병반과 눈, 죽은 가지, 잎자루, 잎, 건전한 가지와 눈, 월동한 과실 등에서 조사를 하였다. 4월에 조사한 결과 병든 가지의 병반에서 93.3% 분리되었으며, 병든 가지 눈에서 46.7% 분리되었으며, 죽은 가지에서 36.7% 병원균이 분리되었다. 잎자루에서 23.3% 분리되었으며, 잎에서 16.7% 분리가 되었으며, 낙과된 과실에서 6.7% 분리되었지만 건전한 가지와 눈에서는 병원균이 분리되지 않았다. 그러나 생육중에 가지, 잎, 잎자루, 과실에 발생한 병든 부위에서는 병원균이 100%분리되었다.

• Journal of Microbiology and Biotechnology
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• 제22권7호
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• pp.889-893
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• 2012

Appressorium is a specialized infection structure of filamentous pathogenic fungi and plays an important role in establishing a pathogenic relationship with the host. The Egh16/Egh16H family members are involved in appressorium formation and pathogenesis in pathogenic filamentous fungi. In this study, a homolog of Egh16H, Magas1, was identified from an entomopathogenic fungus, Metarhizium acridum. The Magas1 protein shared a number of conserved motifs with other Egh16/Egh16H family members and specifically expressed during the appressorium development period. Magas1-EGFP fusion expression showed that Magas1 protein was not localized inside the cell. Deletion of the Magas1 gene had no impact on vegetative growth, conidiation and appressorium formation, but resulted in a decreased mortality of host insect when topically inoculated. However, the mortality was not significant between the Magas1 deletion mutant and wild-type treatment when the cuticle was bypassed by injecting conidia directly into the hemocoel. Our results suggested that Magas1 may influence virulence by affecting the penetration of the insects' cuticle.

• The Plant Pathology Journal
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• 제21권3호
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• pp.297-300
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• 2005

Racodium therryanum from Korea is described here for the first time. This fungus is characterized by that it is isolated from conifer seeds and seedlings, including Abies, colonies are dark green to dark gray and intricate, and it forms chlamydospores in cultures. This pathogenic fungus was isolated from seeds of Abies koreana growing on Mt. Halla, Jeju island. The fungus stopped growth more than at $30^{\circ}C$ but grew even at $O^{\circ}C$. This fungus infected seeds of A. koreana under the snow during winter season. There is a high probability that this fungus affects the natural regeneration of A. koreana on Mt. Halla.

• The Plant Pathology Journal
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• 제26권3호
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• pp.289-292
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• 2010

This study used a modified cetyltrimethylammonium bromide (CTAB) method to efficiently extract DNA from the plant pathogenic fungus Cercospora sojina. Total DNA yield obtained by this method was approximately 1 mg/g of mycelia (fresh weight), and the mean ratio of A260/A280 and A260/A230 were 2.04 and 2.1, respectively. The results of random amplified polymorphic DNA (RAPD) analysis, digestion with restriction enzymes, and Southern hybridization indicated that polysaccharides were effectively removed by this method, and the resulting DNA was sufficient for use in subsequent molecular analysis.

• The Plant Pathology Journal
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• 제19권5호
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• pp.266-268
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• 2003

In 2002, sooty mold was observed on persimmon (Diopyros kald) from the Jinju Agricultural Products Wholesale Market in Gyeongnam, Korea. The lesion of the sooty mold usually appeared as scars or wounds formed on the surface of the fruits. The symptom started with water soaking lesion, then the fruit softened rapidly. Colony of the causal pathogenic fungus was dark green in color on potato dextrose agar. The diameter of growing hyphae was 1-2 $\mu\textrm{m}$. The mostly one-celled conidia were ovoid, lemon or cylinder in shape, blastophores, and sized 46-132 $\mu\textrm{m}$. Erected conidiophores were long-branched chains and their lengths varied from 24 to 346 $\mu\textrm{m}$ with 2-5 $\mu\textrm{m}$ width. The optimum temperature for mycelial growth was about 2$0^{\circ}C$. Based on their mycological characteristics, the fungus was identified as Cladosporium cladosporioides. This is the first report in Korea of the sooty mold of persimmon caused by the said fungus.

• Mycobiology
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• 제48권5호
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• pp.418-422
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• 2020

In 2016, a cercosporoid fungus was found from leaf spot symptoms on melon in Korea. The fungus isolated from the plant was identified based on morphological characteristics and sequence analyses of five genes (ITS rDNA, translation elongation factor 1-α, actin, calmodulin, and histone H3). The fungal isolate was found to be pathogenic to melon. The results confirm that the fungus associated with leaf spot on melon was Cercospora cf. flagellaris. This is the first report of Cercospora cf. flagellaris causing Cercospora leaf spot on melon in Korea.

• Mycobiology
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• 제49권5호
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• pp.498-506
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• 2021

An endophytic fungus strain DYSJ3 was isolated from a stem of Aphanamixis grandifolia Blume, which was identified as Aspergillus versicolor based on the morphological characteristics, internal transcribed spacer (ITS) and calmodulin gene sequences analyses. A. versicolor DYSJ3 exhibited strong antagonistic activity against Colletotrichum musae, C. gloeosporioides and Fusarium oxysporum f. sp. cubense with the inhibition rates of 61.9, 51.2 and 55.3% respectively. The antifungal metabolites mainly existed in the mycelium of A. versicolor DYSJ3, and its mycelial crude extract (CE) had broad-spectrum antifungal activities against plant pathogenic fungi. The CE had a good thermal stability, and the inhibition rate of 100 mg/mL CE against C. musae was above 70.0% after disposing at 120 ℃ for 1 h. Five secondary metabolites were isolated from the CE and identified as averufanin, ergosterol peroxide, versicolorin B, averythrin and sterigmatocystin. Activity evaluation showed versicolorin B exhibited inhibitory effects on the mycelial growth and conidial germination of C. musae, and sterigmatocystin had a weak inhibitory effect on the mycelial growth of C. musae.

• 한국전자현미경학회:학술대회논문집
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• 한국현미경학회 2003년도 제34차 춘계학술대회
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• pp.39-39
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• 2003

• Mycobiology
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• 제43권3호
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• pp.179-183
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• 2015

Zinc is an essential micronutrient required for many enzymes that play essential roles in a cell. It was estimated that approximately 3% of the total cellular proteins are required for zinc for their functions. Zinc has long been considered as one of the key players in host-pathogen interactions. The host sequesters intracellular zinc by utilizing multiple cellular zinc importers and exporters as a means of nutritional immunity. To overcome extreme zinc limitation within the host environment, pathogenic microbes have successfully evolved a number of mechanisms to secure sufficient concentrations of zinc for their survival and pathogenesis. In this review, we briefly discuss the zinc uptake systems and their regulation in the model fungus Saccharomyces cerevisiae and in major human pathogenic fungi such as Aspergillus fumigatus, Candida albicans, and Cryptococcus gattii.

• 분석과학
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• 제9권1호
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• pp.112-117
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• 1996

이탈리안 라이그라스(Lolium multiflorum Lam.) 및 버뮤다그라스와 같은 벼과 잡초에 병해를 일으키는 Bipolaris cynodontis의 배양 추출물로부터 이탈리안 라이그라스 뿌리의 생육저해를 나타내는 3종류의 활성물질을 분리 정제하고 $^1H$, $^{13}C$ 및 2차원 NMR을 포함한 각종 기기분석방법을 통하여 이들 화함물들의 구조를 결정하였다. 이들 화합물들은 저자에 의하여 보고된 바 있는 cochlioquinol이라 명명된 화합물의 유도체들로서 지금까지 보고된 바 없는 새로운 물질이며 숙주식물 중의 하나인 이탈리안 라이그라스에 대하여 활성(20~70%)을 나타내는 것으로 보아 병원균의 병징 발현에 관여하는 것으로 보여진다.