• Journal of Sericultural and Entomological Science
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• v.42 no.2
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• pp.99-103
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• 2000

This study was carried out to investigate incubating characteristics, LTSEM observation, nature of a disease of infected silkworms(bombyx mori), LD$\_$50/, optimum infective condition for mass production and infection percentage(%) on conservation periods. On the V8 media, the colony was 0.5∼2.0cm/8 days in diameter and white or slighty colored with a white fluffy to powdery appearance. The conidia was subglobos in shape, zig-zag appearance, 1-celled, hyaline and 3.2$\times$2.4 ㎛ in size on the average. The conidiophore was irregular grouped, hyaline, rounded or flask-shaped. The LD$\_$50/ values of the 2nd and 4th silkworms were each other 6.6142(Log) in natural temperature and humidity (25$\^{C}$, 65%). On optimum infective condition for mass production, all of preservation time(hr.) postinoculation in 1.0$\times$10$\^$8/ conidia/㎖ was over 97% and only 20 hr in 1.0$\times$10$\^$7/ condia/㎖ was over 90%.

• Korean Journal of Veterinary Service
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• v.30 no.2
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• pp.283-286
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• 2007

Fungus generally doesn't produce toxic or harmful substances so it has low chances to cause food poisoning. However it leads to change appearance, odor and characteristics of the contaminated foods and result in sanitary risk problems. Therefore the contamination of fungi should be prevented since they are not proper for human consumption. Green fungi with white outline raised from the air cell of cooked eggs which were collected by Gyeongi Livestock Veterinary Service in August, 2006. The results came out after the cultivation using Sabouraud's Dextrose Agar(SDA). The conidium appeared white and monospore, the shape of colony was round and oval. Conidiophore was brown and granulated and wrinkles and formed. It was confirmed as Aspergillus nidulans based on the dying using Lactophenol cotton blue, the observation of septum and vesicle from the grown spores, and rDNA sequencing.

• Journal of Veterinary Clinics
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• v.21 no.4
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• pp.413-415
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• 2004

A male Blue-fronted amazon parrot suddenly died after having a history of depression, anorexia and emaciation. At necropsy, numerous well-demarcated yellow to white firm nodules were scattered throughout the left caudal lung lobes and adjacent air sac. Histologically, the wall of air sac was significantly thickened due to necrosis and infiltration of large numbers of fungi and degenerated heterophils. Multifocal necrotizing granulomatous lesions with numerous fungal hypae as well as vasculitis and thrombosis were found in tl1e lung. The fungi had conidiophore, vesicle, phialides and conidia which were characteristic of Aspergillus sp. This is tl1e first report of mycotic air sacculitis and pneumonitis caused by Aspergillus in a parrot in Korea.

• Mycobiology
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• v.50 no.3
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• pp.155-165
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• 2022

Penicillium vietnamense sp. nov. was isolated from Nha Trang Bay, Vietnam in June 2017. It is phylogenetically distinct from the sister species of Penicillium section Charlesia series Indica based on multi-locus sequence typing results using internal transcribed spacer, large subunit ribosomal RNA, b-tubulin, calmodulin, and RNA polymerase II second largest subunit regions. It showed strong growth on Czapek yeast autolysate agar at 37 ℃, a strong acid production on Creatine sucrose agar, and produced short stipes, small vesicles, and subglobose to globose conidia delicately roughened with very short ridges. As the first novel marine fungi species described from Vietnam and discovered in a unique environment, the data could be significant for understanding the taxonomy and geographical distribution of marine fungi in tropical coastal systems such as Vietnam.

• The Korean Journal of Mycology
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• v.41 no.1
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• pp.38-41
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• 2013

In 2010 and 2011, gray mold was found on common fig (Ficus carica) fruit grown at the research field of Jeollabuk-do Agricultural Research and Extension Services, Korea. Gray mold symptoms on common fig fruit mainly occurred after harvest season until December. The typical symptom included brown water-soaked rot and fruit decay. The diseased fruit was covered by gray to brown colored conidiophore and conidia. The conidiophores were tree shape and measured $15-33{\times}2{\mu}m$. Conidia on conidiophore were ellipsoidal or lemon shape, colorless, single cell, and measured $7.3-14.6{\times}6.8-11.1{\mu}m$. The nucleotide sequences of the rDNA ITS region obtained from the pure culture of the gray mold on common fig were 100% similar to the sequences of the GenBank accession number HQ171052, EU519210, HQ171053, FN812726, HM849615, and EU563120 of B. cinerea isolates. In phylogenetic tree, the representative isolate was placed within same clade of B. cinerea. Based on the morphological characteristics and analysis of rDNA ITS sequence data, the fungus was identified as B. cinerea.

• Applied Biological Chemistry
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• v.40 no.4
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• pp.329-333
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• 1997

Phosphate solubilizing microorganisms (1,000 bacteria and 200 fungi) were isolated from soil around Kyungnam and Kyungbook regions using potato dextrose agar-calcium phosphate medium. A fungus with the greatest phosphate solubilizing activity was selected and identified to Penicillium sp. GL-101, based on the morphological characteristics of conidiophore and conidia; flask shape of phialide, simple branching type of conidiophore, and columnar shape of conidial head, in malt extract agar and potato dextrose agar media. The optimum temperature and initial pH to solubilize rock phosphate in potato dextrose broth-rock phosphate medium were $25^{\circ}C$ and pH 7.5, respectively. In these optimum conditions, phosphate solubilizing activities of Penicillium sp. GL-101 against four types of insoluble phosphate: tricalcium-phosphate, aluminium phosphate, hydroxyapatite and rock phosphate, were quantitatively determined. As results, this fungus highly discharged free phosphates to the culture broth with the concentrations of 1,152 ppm against tricalcium-phosphate, 565 ppm against rock phosphate, 292 ppm against aluminium phosphate, and 217 ppm against hydroxyapatite, respectively.

• Research in Plant Disease
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• v.23 no.2
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• pp.202-205
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• 2017

Pink rot appeared in greenhouse-grown sunflower (Helianthus annuus L.) in Jeonju, Korea. The symptoms appeared as brown discoloration of sunflower head and progressed into stem in advanced stage. In order to investigate the causal organism of this disease, we isolated a fungus from the infected seeds and maintained the isolated fungal culture on potato dextrose agar medium. Conidiophores were simple or branched, 62.5 to $123.1{\mu}m$ long. Conidia were produced in basipetal chains, ellipsoidal to pyriform with oblique and prominent truncate basal scars, two-celled, hyaline and measured $10.2-21.4{\times}7.5-12.6{\mu}m$. The fungus was inoculated to a new sunflower plant and showed the typical blight on the leaves. Study of morphological characters, pathogenicity tests and sequence analysis revealed that the isolated fungus is confirmed to be Trichothecium roseum. To our knowledge, this is the first report of pink rot on sunflower caused by T. roseum in Korea.

• The Korean Journal of Mycology
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• v.38 no.2
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• pp.160-166
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• 2010

A homothallic filamentous fungus Aspergillus nidulans has been used as the a model organism for studying growth and development for eukaryotic system. Various studies about specific transcription factors have been performed for elucidating the molecular mechanisms of growth, asexual and sexual developmental processes. Among them, the fkhE gene (AN2025.3) is located in chromosome VII and contains an ORF encoding 718 amino acid polypeptide intervening with two short introns. The cDNA sequencing revealed that at least four types of alternative splicing events were occurred when the fkhE gene was transcribed. The putative FkhE polypeptide contains a conserved forkhead domain and a bipartite nuclear localization signal at it's N-terminus and C-terminus, respectively. Deletion of fkhE resulted in impaired conidiophore formation in a solid medium. However, the sexual developmental process or cleistothecia formation was normal. Furthermore, fkhE deletion mutant produced conidiophores and conidia under the submerged culture, indicating that the fkhE gene is involved in asexual developmental process similar to the fkhF gene.

• Mycobiology
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• v.46 no.2
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• pp.172-176
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• 2018

A new species belonging to the genus Alternaria was isolated from the necrotic leaf spots of Brassica rapa subsp. pekinensis in Yuseong district, Daejeon, Korea. It is an occasional isolate, not an etiological agent, which is morphologically similar to A. broccoli-italicae, but differs in conidial size and conidiophore shape. Phylogenetic analysis using the sequence datasets of the internal transcribed spacer (ITS) region of the rDNA, glyceraldehyde-3-phosphate dehydrogenase (gpd), and plasma membrane ATPase genes showed that it is distantly related to A. broccoli-italicae and closely related to Alternaria species in the section Pseudoalternaria, which belonged to a clade basal to the section Infectoriae. Morphologically, the species is unique because it produces solitary conidia or conidial chains (two units), unlike the four members in the section Pseudoalternaria that produce conidia as short branched chains. It exhibits weak pathogenicity in the host plant. This report includes the description and illustration of A. brassicifolii as a new species.

• The Plant Pathology Journal
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• v.15 no.1
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• pp.44-47
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• 1999

Fungal isolates belong to Fusarium solani (perfect stage : Nectria haematococca) were isolated form pea, ginseng roots and soybean during 1995 and 1996 in Korea. Thirty-five isolates were identified as F. solani f. sp. pisi based on the morphological characteristics and their pathogenicity. Microconidia formed on the long conidiophore were ovoid or oblong sizing 5~14 x 2.5~5.0 $\mu\textrm{m}$. Macroconidia were formed on carnation leaf agar media with 4.8~5.3 x 32.0~40.7 $\mu\textrm{m}$ in size. They belonged to $\beta$-type since their 3-septate macroconidia were smaller than $5\mu\textrm{m}$ in width. Chlamydospores were smooth- or rough- walled and formed in terminal or lateral branches of hyphae, intercalary, or in chains. Most isolates were highly virulent to pea seedlings, producing dark brown or rot lesions. This is the first report of f. solani f. sp. pisi being pathogenic to pea in Korea.