• 한국균학회지
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• 제20권2호
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• pp.95-108
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• 1992

1991년도 8월부터 11월까지 4개 도(道)의 9지역에서 19종의 콩과식물뿌리 주변토양에서 65 토양시료를 채취하여, 내생균근균에 대한 기본 연구를 하였다. 여기서 분리된 내생균근균은 4속 21종이였으며, 이중에 6종이 미기록종으로 나타나서 여기서 새로이 서술하였다 : Acaulospora elegans, A. undulata, Glomus laminated spores cf. marcrocarpus var. macrocarpus, Gl. WUM1+3, Gl. scintillans, Scutetlospora verrucosa. 또한 미동정된 3종은 아직 종동정에 어려웠으며, Acaulospora sp., Glomus sp. 및 Scutellospora sp.의 각각 한종씩 분리하여 속기재를 하였다.

• 대한화학회지
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• 제15권5호
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• pp.256-265
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• 1971

An ESR study has been made on free radicals produced in frozen aqueous solutions (ices) of glycine, DL-${\alpha}$-alanine, DL-serine, L-cysteine, DL-leucine and DL-isoleucine by gamma-irradiation at dry ice temperature. All free radicals induced were decayed concomitant to the successive annealing but the radical species which is believed to be dominant seems to be stable even near the melting point of the ice. These dominant species were found to be identical to those resulted from direct action of radiation in the solid at room temperature. Small but significant changes in the spectra of glycine and DL-${\alpha}$-alanine were observed by varying the microwave power. These results seem to support the view that the spectra obtained were composite consisting of more than two different resonances having different power saturation characteristics. The relative contribution of unidentified resonances to the composite spectra was greater for solutions of low concentration. These resonances are assumed to be induced by indirect effects, mainly hydrogen abstraction by radiation produced hydroxyl radicals and also C-N bond cleavage by hydrated electrons.

• 한국균학회지
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• 제22권4호
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• pp.355-365
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• 1994

1991년부터 1994년까지 우리나라에서 흰가루병균을 침해하는 중복기생균의 발생에 관한 전면적인 조사를 실시하였다. 그 결과 총 1070점의 흰가루병 이병식물을 채집하였는데 이중 92점의 시료에서 중복기생균의 존재가 확인되었다. 이중 6점의 시료를 침해한 중복기생균은 동정되지 않았으나 나머지 86점의 시료에서는 모두 Ampelomyces quisqualis가 중복기생균으로 확인되었다. 이는 중복기생균의 흰가루병균 침해가 자연계에서 흔한 현상임을 나타내주었고 우리나라에서도 A. quisqualis가 가장 흔한 중복기생균임을 나타내 주었다. 1992년 채집시료 32점 중 24점에서 순수분리된 A. quisqualis균주는 모두 오이 흰가루병균인 Sphaerotheca fusca에 병원성을 나타내었다.

• Journal of Microbiology and Biotechnology
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• 제25권1호
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• pp.1-10
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• 2015

The bacterial diversity of 10 marine sponges belonging to the species Cliona celata, an unidentified Cliona species, Haliclona cinerea, Halichondria okadai, Hymeniacidon sinapium, Lissodendoryx isodictyalis, Penares incrustans, Spirastrella abata, and Spirastrella panis collected from Jeju Island and Chuja Island was investigated using amplicon pyrosequencing of the 16S rRNA genes. The microbial diversity of these sponges has as of yet rarely or never been investigated. All sponges, except Cliona celata, Lissodendoryx isodictyalis, and Penares incrustans, showed simple bacterial diversity, in which one or two bacterial OTUs occupied more than 50% of the pyrosequencing reads and their OTU rank abundance curves saturated quickly. Most of the predominant OTUs belonged to Alpha-, Beta-, or Gammaproteobacteria. Some of the OTUs from the sponges with low diversity were distantly (88%~89%) or moderately (93%~97%) related to known sequences in the GenBank nucleotide database. Phylogenetic analysis showed that many of the representative sequences of the OTUs were related to the sequences originating from sponges and corals, and formed sponge-specific or -related clades. The marine sponges investigated herein harbored unexplored bacterial diversity, and further studies should be done to understand the microbes present in sponges.

• 한국수산과학회지
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• 제52권6호
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• pp.740-744
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• 2019

Pacific white-sided dolphins Lagenorhynchus obliquidens inhabit cool temperate waters; in Korean waters, they concentrate near the coast of Gangwon and Gyeongbuk from late autumn to early spring. We collected 15 individuals from Yeongduk, Gyeongju, Ulsan, and Busan between December 2018 and February 2019 and analyzed their stomach contents. Fresh prey items were identified to the species level, and residual stomach contents that were unidentified due to digestion were filtered through a sieve to find fish otoliths and cephalopod beaks. The most important prey items of Pacific white-sided dolphins were cephalopods, composing 68.0% of the diet by occurrence. Fishes were the second largest dietary component, making up 32.0% of the diet by occurrence. Of the cephalopod species consumed, Watasenia scintilans was the principal prey item.

• 환경생물
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• 제25권3호
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• pp.205-214
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• 2007

Marine environmental characteristics on the dinoflagellate cysts distribution in surface sediment of the southwest sea of Korea were investigated from 21 stations in September 2003, and 36 stations in June, 2004. The water mass characteristics indicated that the southwest sea of Korea is characterized by various oceanographic conditions due to coastal waters of Korea and China. The Tsushima warm currents and the cold bottom water of the Yellow Sea. Mud contents and chlorophyll a concentrations were higher in central region such as, Namhaedo, Yeosu and Goheung coast than in western region such as, Wando, Haenam and Jindo coast in the South Sea of Korea. A total of 35 taxa of dinoflagellate cysts were identified representing 21 genera, 33 species, 2 unidentified species. Cyst abundance ranged from 13 to 527 cysts $g-dry^{-1}$, showing higher abundance in the coastal areas than in western region of the South Sea of Korea. From the result of the PCA analysis, the distribution of dinoflagellate cysts was not only related to the different water masses which appeared in the southwestern sea but also to physical and biological parameters such as water temperature, light, surface sediment faces and phytoplankton biomass.

• 한국작물학회지
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• 제51권6호
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• pp.497-504
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• 2006

Biodiversity is closely related to the conservation of ecosystems. Ecosystems provide more subtle, but equally essential, services. Microorganisms decompose human's waste and renew the soils that produce our food crops. Biodiversity in Korean paddies encompass 54 families and 107 species of freshwater invertebrates. In terms of the number of aquatic insects affected by different sources, the order starting with the highest population was swine slurry > chemical fertilizer > fresh straw with reduced fertilizers > control. The number of freshwater invertebrate and aquatic macro-invertebrate in surface water of the plots without insecticidal application were 2 and 2.1 times greater than in fields receiving insecticide applications, respectively. The soil microfungal flora of the 85 isolates paddy fields in Korea was 30 species in 13 genera and 11 isolates were unidentified yet. Agricultural policy should be changed to assist the conservation of biodiversity because until now the agricultural ecosystems have been negatively affected from the development of high-yield varieties to enhance food production, and the expansion of fertilizer and chemical use. For the conservation of agricultural ecosystems, agricultural practices with less investment and more resource saving, as well as enhancing the safety of agricultural and livestock products are essential. Finally, this paper was written for the contribution for the development of environmentally friendly farming systems with neighboring or whole ecosystems.

• ALGAE
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• 제21권2호
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• pp.217-228
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• 2006

Seasonal compositions, standing crops and trophic status of phytoplankton were investigated at 13 sites of Suwon-si, Gyeonggi-do from June, 2004 to March, 2005. Total of 304 taxa were found, and classified as 4 phylums 4 classes 13 orders 36 families 93 genera 246 species 47 varieties 8 forms and 3 unidentified species by Engler’s classification system. Judged by standing crops of phytoplakton, algal blooming was observed at every sampling sites except Pajang reservoir, Hagwanggyo reservoir, Suwon-cheon and Woncheon-cheon throughtout the whole study periods. While Hagwanggyo reservoir appeared to be in mesotrophic or oligomesotrophic status, most of the remaining sampling sites in Suwon-si were in eutrophic status according to trophic status index. In this study, the most abundant taxa revealed in eutrophic status were Anabaena circinalis, Pandorina morum, Scenedesmus acuminatus, and S. quadricauda as previously reported as the most abundant taxa in eutrophic status. But Navicula cryptocephala and Cyclotella stelligera, reported as the abundant taxa of mesotrophic and oligomesotrophic status, respectively, occurred in eutrophic status in this study.

• Animal Systematics, Evolution and Diversity
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• 제35권1호
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• pp.33-36
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• 2019

The marine interstitial annelid Pharyngocirrus uchidai(Sasaki, 1981) has been only known from Japan. In this study, we report the occurrence of P. uchidai for the first time in four localities along the eastern coast of Korea: Bukmyeon, Gamchu, Gase, and Oeongchi. Species identification was confirmed by comparison of DNA barcoding sequences with morphological examination from the type locality, Oshoro, Japan. We generated a total of 25 sequences of a partial segment (580 bp) of the cytochrome c oxidase subunit I gene (COI), representing five specimens from each locality. Maximum intra-specific variation was 1.2% in terms of Kimura two-parameter (K2P) distance, observed between two individuals each from Gamchu (i.e., between two specimens from the single locality), Gamchu and Oeongchi, Gamchu and Oshoro, and Oeongchi and Oshoro. On the other hand, an identical haplotype was found in all the five localities, substantiating our species identification for the Korean populations. Inter-specific K2P distance between P. uchidai and an unidentified Saccocirrus sp. from Canada (based on public database entries) was 22.4-23.4%.

• Journal of Species Research
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• 제10권1호
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• pp.1-11
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• 2021

Evidence highlighting the importance of gut microbiota in biodiversity conservation is growing; however, gut bacteria in South Korean wildlife have not been well identified. Using a culture-dependent isolation method, we identified the gut bacteria from Korean aquatic wildlife: the gazami crab (Portunus trituberculatus), Korean striped bitterling (Acheilognathus yamatsutae), oily bitterling (Acheilognathus koreensis), leopard mandarin fish (Siniperca scherzeri), Korean dark chub (Zacco koreanus), diving beetle (Cybister lewisianus), spotted steed (Abbottina springeri), and Korean spotted sleeper (Odontobutis obscura interrupta). We identified 18 strains previously unrecorded in South Korea by comparing 16S rRNA gene sequences of isolates against the EzBioCloud and National Institute of Biological Resources(NIBR) databases. The isolated strains belong to the phyla Actinobacteria, Bacteroidetes, Firmicutes, and Proteobacteria. We also assessed for phylogenetic relatedness, Gram-stain reaction, colony and cell morphology, and biochemical characteristics. Basic information and 16S rRNA gene sequences of the isolates were registered in NIBR, and NIBR accession numbers are provided.