• Genomics & Informatics
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• v.13 no.4
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• pp.102-111
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• 2015

The karyotypes of most species of crocodilians were studied using conventional and molecular cytogenetics. These provided an important contribution of chromosomal rearrangements for the evolutionary processes of Crocodylia and Sauropsida (birds and reptiles). The karyotypic features of crocodilians contain small diploid chromosome numbers (30~42), with little interspecific variation of the chromosome arm number (fundamental number) among crocodiles (56~60). This suggested that centric fusion and/or fission events occurred in the lineage, leading to crocodilian evolution and diversity. The chromosome numbers of Alligator, Caiman, Melanosuchus, Paleosuchus, Gavialis, Tomistoma, Mecistops, and Osteolaemus were stable within each genus, whereas those of Crocodylus (crocodylians) varied within the taxa. This agreed with molecular phylogeny that suggested a highly recent radiation of Crocodylus species. Karyotype analysis also suggests the direction of molecular phylogenetic placement among Crocodylus species and their migration from the Indo-Pacific to Africa and The New World. Crocodylus species originated from an ancestor in the Indo-Pacific around 9~16 million years ago (MYA) in the mid-Miocene, with a rapid radiation and dispersion into Africa 8~12 MYA. This was followed by a trans-Atlantic dispersion to the New World between 4~8 MYA in the Pliocene. The chromosomes provided a better understanding of crocodilian evolution and diversity, which will be useful for further study of the genome evolution in Crocodylia.

• Mycobiology
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• v.45 no.3
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• pp.123-128
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• 2017

A severe leaf spot, turning to foliage blight, was observed on leaves of Maranta leuconeura growing in a garden in Brazil (state of Rio de Janeiro) in 2015. A dematiaceous hyphomycete bearing a morphology typical of a helminthosporoid fungi was regularly found in association with diseased tissues. The fungus was isolated and pathogenicity was demonstrated through the completion of Koch's postulates. A morphology and molecular analysis led to the conclusion that the fungus belonged to the genus Bipolaris, which is characterized by having fusiform conidia, externally thickened and truncate hila and a bipolar pattern of germination. Additionally, homology of internal transcribed spacer and GAPDH sequences with sequences of other Bipolaris species, confirmed its generic placement. A phylogenetic study also indicated clearly that the fungus on M. leuconeura is phylogenetically distinct from related species of this genus, leading to the proposal of the new species Bipolaris marantae.

• Mycobiology
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• v.45 no.3
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• pp.139-149
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• 2017

The genus Hyaloperonospora (Peronosporaceae; Oomycota) is an obligate biotrophic group that causes downy mildew disease on the Brassicaceae and allied families of Brassicales, including many economically relevant crops, such as broccoli, cabbage, radish, rape, and wasabi. To investigate the diversity of Hyaloperonospora species in northeast Asia, we performed a morphological analysis for the dried herbarium specimens collected in Korea, along with molecular phylogenetic inferences based on internal transcribed spacer rDNA and cox2 mtDNA sequences. It was confirmed that 14 species of Hyaloperonospora exist in Korea. Of these, three species, previously classified under the genus Peronospora, were combined to Hyaloperonospora: H. arabidis-glabrae comb. nov. (ex Arabis glabra), H. nasturtii-montani comb. nov. (ex Rorippa indica), and H. nasturtii-palustris comb. nov. (ex Rorippa palustris). In addition, finding two potentially new species specific to northeast Asian plants is noteworthy in support of the view that the species abundance of Hyaloperonospora has been underestimated hitherto.

• Journal of Species Research
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• v.9 no.3
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• pp.210-217
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• 2020

Microseira wollei (Farlow ex Gomont) G.B.McGregor and Sendall ex Kennis, a mat-forming filamentous harmful cyanobacterium, has historically been found in the United States. Microseira wollei produces neurotoxins and hepatotoxins which affect declining water quality. In the present research, we report of unrecorded M. wollei with morphology, TEM anatomy, molecular phylogeny on the Korean population. Based on 16S rRNA gene sequences, Korean population were different by 0.02% (2 bp) to the Japanese population, 1.2-1.3% to the Australian population, and 2.5-3.7% to the United States populations. nifH gene sequences were 8.4-8.7% different to Australian ones and 3.5-3.8% to other population, however molecular phylogenetic analysis of M. wollei living in Korea revealed monophyly with the geographical populations of U.S.A., Australia, and other geographical populations. Since the mat of M. wollei has been reported to be maintained for several years in other countries, it is necessary further investigate the seasonal and regional distribution of this species in Korea.

• Mycobiology
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• v.44 no.1
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• pp.1-6
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• 2016

Ganoderma lucidum has a long history of use as a traditional medicine in Asian countries. However, the taxonomy of Ganoderma species remains controversial, since they were initially classified on the basis of their morphological characteristics. Recently, it was proposed that G. lucidum from China be renamed as G. sichuanense or G. lingzhi. In the present study, phylogenetic analysis using the internal transcribed spacer region rDNA sequences of the Ganoderma species indicated that all strains of the Korean 'G. lucidum' clustered into one group together with G. sichuanense and G. lingzhi from China. However, strains from Europe and North American, which were regarded as true G. lucidum, were positioned in a clearly different group. In addition, the average size of the basidiospores from the Korean cultivated Yeongji strains was similar to that of G. lingzhi. Based on these results, we propose that the Korean cultivated Yeongji strains of 'G. lucidum' should be renamed as G. lingzhi.

• The Korean Journal of Mycology
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• v.48 no.2
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• pp.87-93
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• 2020

A fungal strain designated KNU-WDM2A2 was isolated from mosquitoes in Gimcheon, Korea. The pure culture was transferred to potato dextrose agar (PDA) and synthetic nutrient agar (SNA) media and attained a diameter of 90 mm after 10 days of incubation at 25℃. The colonies were whitish to light pink and cottony to wooly, with an abundant production of aerial mycelia. The strain produced hyaline to slightly yellowish conidiophores that were rough-walled and branched, with conidiogenous cells arising terminally or laterally. Conidia were unicellular, hyaline to light brown, smooth, and oval or ovoid to clavate, with a size of 4.1-6.9×2.5-3.3 ㎛ (n=65). A phylogenetic analysis was conducted using the internal transcribed spacer (ITS) regions and 28S rDNA of large subunit (LSU) sequences, to support the cultural and morphological characteristics. The KNU-WDM2A2 strain was identified here as Biscogniauxia petrensis, new to Korea.

• Korean Journal of Plant Taxonomy
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• v.48 no.3
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• pp.206-217
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• 2018

The nucleotide sequences of the chloroplast rbcL, matK, and psbA-trnH and nuclear internal transcribed spacer (ITS) regions were determined from all species of Viburnum in Korea with multiple accessions to reconstruct the phylogeny and to evaluate the utility of the DNA sequences as DNA barcodes. The results of phylogenetic analyses of the cpDNA and ITS data are consistent with the findings of previous studies of Viburnum. Four morphologically closely related species, V. dilatatum, V. erosum, V. japonicum, and V. wrightii, were included in a strongly supported sister clade of V. koreanum and V. opulus. Viburnum odoratissimum is suggested to be sister to the V. dilatatum/V. koreanum clade in the cpDNA data, while V. odoratissimum is a sister to V. furcatum in the ITS data. Viburnum burejaeticum and V. carlesii are strongly supported as monophyletic. Our analyses of DNA barcode regions from multiple accessions of the species of Viburnum in Korea confirm that six out of ten species in Korea can be discriminated at the species level. The V. dilatatum complex can be separated from the remaining species according to molecular data, but the resolution power to differentiate a species within the complex is weak. This study suggests that regional DNA barcodes are useful for molecular species identification in the case of Viburnum when flowering or fruiting materials are not available.

• The Korean Journal of Mycology
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• v.45 no.1
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• pp.83-89
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• 2017

An unrecorded fungal species in Korea, Diaporthe tectonae was isolated from soil in Jeon-ju of Korea. The isolate was characterized morphologically, and a phylogenetic analysis using a combined dataset of internal transcribed spacer, ${\beta}-tubulin$, and elongation factor $1-{\alpha}$ sequences indicated its similarity to D. tectonae strains reported previously. To our knowledge, this is the first report of D. tectonae in Korea.

• Mycobiology
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• v.44 no.4
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• pp.237-247
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• 2016

Aspergillus (Trichocomaceae, Eurotiales, and Ascomycota) is a genus of well-defined asexual spore-forming fungi that produce valuable compounds such as secondary metabolites and enzymes; however, some species are also responsible for diseases in plants and animals, including humans. To date, 26 Aspergillus species have been reported in Korea, with most species located in terrestrial environments. In our study, Aspergillus species were isolated from mudflats and sea sand along the western and southern coasts of Korea. A total of 84 strains were isolated and identified as 17 Aspergillus species in 11 sections on the basis of both morphological characteristics and sequence analysis of the calmodulin gene (CaM) locus. Commonly isolated species were A. fumigatus (26 strains), A. sydowii (14 strains), and A. terreus (10 strains). The diversity of Aspergillus species isolated from mudflats (13 species) was higher than the diversity of those from sea sand (five species). Four identified species-A. caesiellus, A. montenegroi, A. rhizopodus, and A. tabacinus-are in the first records in Korea. Here, we provide detailed descriptions of the morphological characteristics of these four species.

• Mycobiology
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• v.45 no.4
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• pp.263-269
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• 2017

The genus Peronospora, an obligate biotrophic group belonging to Oomycota, causes serious damage to a variety of wild and ornamental plants, as well as cultivated crops, such as beet, rose, spinach, and tobacco. To investigate the diversity of Peronospora species parasitic to Stellaria and Pseudostellaria (Caryophyllaceae) plants in Korea, we performed a morphological analysis on dried herbarium specimens and molecular phylogenetic inferences based on internal transcribed spacer rDNA and cox2 mitochondrial DNA sequences. As a result, it was confirmed that there are four species of Peronospora parasitic to specific species of Stellaria and Pseudostellaria, all of which were hitherto unrecorded in Korea: P. alsinearum (ex Stellaria media), P. stellariae-aquaticae (ex Stellaria aquatica), P. stellariae-uliginosae (ex Stellaria alsine), and P. pseudostellariae (ex Pseudostellaria palibiniana). In addition, Peronospora specimens parasitic to Pseudostellaria davidii differed morphologically from P. pseudostellariae owing to the large and ellipsoidal conidia; this morphological discrepancy was also validated by the high genetic divergence between the two species. Peronospora casparyi sp. nov. is described and illustrated here.