• Proceedings of the Korean Society of Plant Pathology Conference
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• 2003.10a
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• pp.130-130
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• 2003

Gummy stem blight pathogen is very difficult not only to monitor the inoculum levels prior to host infection, and also it is destructive and hard to control in field condition. We have applied RAPD technique to elucidate the genetic diversity of the genomic DNA of Didymella bryoniae and also to generate specific diagnostic DNA probe useful for identification and detection. The 40 primers produced clear bands consistently from the genomic DNA of twenty isolates of Didymella bryoniae, and two hundred seventy-three amplified fragments were produced with 40 primers. The combined data from 273 bands was analyzed by a cluster analysis using UPGMA method with an arithmetic average program of NTSYS-PC (Version 1.80) to generate a dendrogram. At the distance level of 0.7, two major RAPD groups were differentiated among 20 strains. RAPD group (RG) I included 8 isolates from watermelon except one isolate from melon. RAPD group (RG) IV included 12 isolates from squash, cucumber, watermelon and melon.. In amplification experiment with SCAR specific primer RG1F-RG1R resulted in a single band of 650bp fragment only for 8 isolates out of 20 isolates that should be designated as RAPD Group 1. However, same set of experiment done with RGIIF-RGIIR did not result in any amplified product.. Our attempts to detect intraspecific diversity of ITS region of rDNA by amplifying ITS region and 17s rDNA region for 20 isolates and restriction digestion of amplified fragment with 12 enzymes did not reveal polymorphic band. In order to develop RAPD markers for RGIV specific primer, a candidate PCR fragment( ≒1.4kb) was purified and Southern hybridized to the amplified fragment RGIV isolates. This promising candidate probe recognized only RGIV isolates

• ALGAE
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• v.33 no.4
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• pp.291-304
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• 2018

Lyngbya C. Agardh ex Gomont is a nonheterocytous cyanobacterial genus whose evolutionary history is still poorly known. The traditionally defined Lyngbya has been demonstrated to be polyphyletic, including at least five distinct clades, some of which have been proposed as new genera. Intraspecific diversity is also clearly underestimated in Lyngbya due to the lack of unique morphological characters to differentiate species. In this study, we describe the new genus Capillus T. A. Caires, C. L. Sant'Anna et J. M. C. Nunes from benthic marine environments, including two new Brazilian species (here described as C. salinus T. A. Caires, C. L. Sant'Anna et J. M. C. Nunes, and C. tropicalis T. A. Caires, C. L. Sant'Anna et J. M. C. Nunes), and two species yet to be described, one of them from India (Capillus sp. 2.1), and the other from United States of America, based on strain PCC 7419. Capillus species presented cross-wise diagonal fragmentation, assisted or not by necridic cells, which has not been previously mentioned for Lyngbya. Ultrastructural analyses showed that C. salinus and C. tropicalis have numerous gas vesicles, which are rarely described for benthic marine species. The new genus formed a well-supported clade, and the D1-D1' and Box B secondary structures of internal transcribed spacer also supported the proposal of its new species. These findings help to clarify the diversity of species in the Lyngbya complex and the taxonomy of the group, and highlight the need of further floristic surveys in tropical coastal environments, which remain poorly studied.

• Korean Journal of Weed Science
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• v.8 no.3
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• pp.317-323
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• 1988

This survey was conducted to know characterization of weed occurrence under protected culture conditions at Yousong in 1985. Chenopodium album, Polygonum hydropiper, Portulaca oleracea and Digitaria sanguinalis were dominated in outdoor, whereas Capsella bursa-pastoris, C. album, D. sanguinalis and P. oleracea were dominant in polyethylene house. More weeds emerged in mulching plots and dry weight of weeds was greater in non-mulching plots. Summer broadleaf weeds and summer grasses were abundant in outdoor, whereas non-mulching plots in polyethylene house was dominated by winter broadleaf weeds, and mulching plots in polyethylene house were dominated by winter grasses and winter broadleaf weeds in early stage and summer grasses and summer broadleaf weeds in late stage. Simpson index was high in polyethylene house and Shannon's diversity index, maximum diversity for the Shannon diversity index were lower than eveness using the Shannon diversity index and this trend was more remarkable in mulching and mulching in tunnel than in non-mulching under polyethylene house condition. Shannon diversity index, maximum diversity for the Shannon diversity index were high in mulching or tunnel, and Simpson index was high in non-mulching in outdoor condition. Interspecific competition was more severe than intraspecific competition in both conditions.

• Korean Journal of Plant Resources
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• v.23 no.6
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• pp.541-549
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• 2010

The present study researched morphological characteristics and analyzed the genetic diversity by using RAPD in Calanthe species, native plant in Jeju, Korea. Twenty-six samples were selected by flower color, and 19 horticultural traits were investigated to study morphological characteristics. The C. discolor had the smallest leaf, the length and width of dorsal sepal, lateral sepal, petal, central lip, lateral lip, and flower stalk length were shortest and/or smallest except the spur and ovary length in Calanthe species, but those of Calanthe discolor for. sieboldii (Dence.) Ohwi (Calanthe discolor for. sieboldii) were the largest and/or biggest, and those of variants were the intermediate between C. discolor and C. discolor for. sieboldii, but spur length was the longest in C. discolor, the shortest in C. discolor for. sieboldii, and intermediate in the variants. Ovary length in C. discolor was shortest and C. discolor for. sieboldii and variants were similar with each other. The flower colors of C. discolor were brownish red, the value of CIE Lab was between 40 and 50. The flower color of C. discolor for. sieboldii was yellowish; the value of CIE Lab was between 110 and 130. And variants had various colors between 50 and 70 in the value of CIE Lab. After analyzing multiple band patterns of PCR products, 154 bands were selected as polymorphic RAPD markers. The analysis of Genetic distance of Calanthe species using RAPD showed that C. discolor and C. discolor for. sieboldii are more distant from each other than variants, and demonstrated the fact that genetic position of variants is between the other two species.

• Journal of Microbiology and Biotechnology
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• v.9 no.1
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• pp.78-83
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• 1999

Thirty-six environmental isolates of Vibrio vulnificus obtained from seawater, sediments, and raw seafoods, and 18 clinical isolates from Vibrio septicemia patients were typed by restriction endonuclease digestion profiles (REDP) of genomic DNA with SfiI. The results revealed a high-level of variation in REDPs, indicating a vast genomic diversity among V. vulnificus strains. Genetic relatedness of the strains showed similarities ranging from 10％ to 100％. Different REDPs for isolates from various raw seafoods were obtained, and clustering of strains according to type of seafoods was not observed. In contrast, clinical isolates of V. vulnificus showed higher similarity to one another, and could be subdivided into one separate group. The difference in REDPs of the V. vulnificus isolates from clinical origin and from raw seafoods substantiates the previous observation that only a single type of pathogenic strain was involved in each human infection, despite the numerous genetically polymorphic strains found from implicated oysters.

• Animal Systematics, Evolution and Diversity
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• v.21 no.1
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• pp.93-110
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• 2005

A taxonomic study on the genus Mesocyclops has been accomplished as one of the serial researches on the freshwater cyclopoid cope pods in South Korea. As a result, five species are recognized: M. leuckarti (Claus), M. pehpeiensis Hu, M. dissimilis Defaye and Kawabata, M. woutersi Van de Verde, and M. mariae Guo. Of these, M. dissimilis, M. woutersi, and M. mariae are new to Korean fauna. Morphological details of each species and the intraspecific variabilities are commented. A key to the species of genus Mesocyclops known from Korea is provided.

• Animal Systematics, Evolution and Diversity
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• v.21 no.2
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• pp.137-156
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• 2005

A taxonomic study on the Eucyclops serrulatus species group has been accomplished as one of the serial researches on the freshwater cyclopoid copepods in Korea. As a result, the 'Eucyclops serrulatus', hitherto known from Korea through many reports and papers, turns out to be a species complex of six sibling species: E. serrulatus (Fischer), E. roseus Ishida, E speratus (Lilljeborg), E. pacificus Ishida, E. ohtakai Ishida, and I tsushimensis Ishida Taxonomic accounts on their detailed interspecific discrepancies and intraspecific variabilities are presented. A key to the Eucyclops serrulatus group from the Far East is also provided.

• Animal Systematics, Evolution and Diversity
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• v.27 no.2
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• pp.159-163
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• 2011

DNA barcoding of Bryozoa or "moss animals" has hardly advanced and lacks reference sequences for correct species identification. To date only a small number of cytochrome c oxidase subunit I (COI) sequences from 82 bryozoan species have been deposited in the National Center for Biotechnology Information (NCBI) GenBank and Barcode of Life Data Systems (BOLD). We here report COI data from 53 individual samples of 29 bryozoan species collected from Korean seawater. To our knowledge this is the single largest gathering of COI barcode data of bryozoans to date. The average genetic divergence was estimated as 23.3% among species of the same genus, 25% among genera of the same family, and 1.7% at intraspecific level with a few rare exceptions having a large difference, indicating a possibility of presence of cryptic species. Our data show that COI is a very appropriate marker for species identification of bryozoans, but does not provide enough phylogenetic information at higher taxonomic ranks. Greater effort involving larger taxon sampling for the barcode analyses is needed for bryozoan taxonomy.

• Animal Systematics, Evolution and Diversity
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• v.36 no.3
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• pp.240-250
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• 2020

Member of the genus Tobrilus Andrássy, 1959, which belongs to Tobrilidae Filipjev, 1918, are known as free-living nematodes in freshwater habitat. This genus was previously unknown from Korea. Five Tobrilus species are here reported for the first time from Korea: Tobrilus aberrans (Schneider, 1925), Tobrilus diversipapillatus (Daday, 1905), Tobrilus gracilis (Bastian, 1865), Tobrilus longus (Leidy, 1851), and Tobrilus wesenbergi (Micoletzky, 1925). Specimens were collected from sediments of the Nakdong River in Korea. Morphological characters and measurements of the specimens generally agree with the original descriptions of Tobrilus species, except for some differences that can be attributed to intraspecific variation among populations(e.g., nerve ring position [% pharynx] and reproductive length). Each species can be distinguished from other members of the genus by specific characters (e.g., cephalic setae length and position, buccal cavity and pocket shape, vulva position, degree of development of reproductive system, and tail length and shape). Here, five species in the genus Tobrilus are fully redescribed and illustrated using optical microscopy images. DNA barcode sequence information (the D2-D3 region of 28S rDNA) is also provided for molecular species identification.

• Animal Systematics, Evolution and Diversity
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• v.37 no.4
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• pp.273-279
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• 2021

Branchinotogluma segonzaci (Miura and Desbruyères, 1995) occurs in hydrothermal vent fields of the southwestern Pacific Ocean. We morphologically compared B. segonzaci from the North Fiji Basin with the original description from the Lau Basin and a subsequent study of specimens from the Manus Basin. The main characteristics of all B. segonzaci populations were similar having 21 segments, 10 pairs of elytra, cylindrical-shaped anterior lobes, and ventral papillae on segment 12 and ventral lamellae on segments 13-17 in males. However, the specimens from the North Fiji Basin had rounded to sub-renifrom elytra rather than oval in the original description. Additionally, we newly obtained 11 cytochrome oxidase subunit I (COI) DNA barcodes from the North Fiji Basin and Tonga Arc populations and compared them with known COI DNA barcodes of Branchinotogluma species. Thirteen sequences of B. segonzaci showed 0.0-1.07% intraspecific variation and formed two clades in the COI neighbor-joining tree, whereas the interspecific variation among Branchinotogluma species was 8.19-22.4%. The results of this study contribute to biogeographic studies of B. segonzaci and the evolution of polynoid scale worms in chemosynthesis-based ecosystems.