• Korean Journal of Soil Science and Fertilizer
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• v.28 no.4
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• pp.356-362
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• 1995

This experiment was carried out to investigate the effects on the seasonal population change of microflora of long-term application of organic matters in Fluvio-Alluvial plain of Jeonbug series. As organic matters, rice straw and compost of 5 and 10ton/ha, which were applied with the different nitrogen fertilizer level of 0, 150kg/ha into the soil 15cm deep, respectively. A number of total aerobic bacteria were gradually increased from just after water-logging before rice transplanting to pancle formations stage, afterthat decreased at harvest. The other side, a number of actinomycetes, fungi and cellulose-decomposers were slightly fluctuated until panicle formation stage and increased at havesting stage. In general, microorganism numbers were higher in organic matter with long-term nitrogen fertilizer applied plot, while cellulose-decomposers were higher in only organic matter applied plot. The microorganisms of ammonia-oxidizing, nitrate-reducing and nitrite-oxidizing, and denitrifying bacteria showed the maximum number at harvest stage, at panicle formation stage and at early tillering stage, respectively, while that of ammonifying bacteria were variable if nitrogen fertilizer applied or not at the respective periods in nitrogen cycle under water-logging. These bacteria were numerous in the organic matter plots combined with nitrogen fertilizer, especially, denitrifying bacteria in rice straw, others no difference.

• The Korean Journal of Mycology
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• v.13 no.4
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• pp.195-201
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• 1985

Numbers of total bacteria and fungal propagules were highly populated in the soil of diseased plot in Gumsan, whereas numbers of actinomycetes were high in the soil of healthy plot in Goesan. In microbial fluctuation of different soil conditions four weeks after amended with various plant materials, bacteria were decreased in the soil amended with various plant materials as compared with non-amended soil except for Goesan. On the contrary, numbers of fungal propagules were increased amended with onion and potato stalk in two soils at different conditions, and also the propagules were enhanced in the soil amended with various plant materials in general. Higher numbers of bacteria and fungal propagules were observed in the diseased replanted plot in general, but germination rate of fungal spores relatively reversed against the microbial population. Alternaria panax was not affected much in their germination by natural soil condition, while Fusarium spp. were affected in their germination by natural soil. Natural soil showed a fungistatic effect against four fungal spores.

• Culinary science and hospitality research
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• v.17 no.3
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• pp.141-150
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• 2011

The objective of this study is to monitor the microbiological effect on preschool children's hand safety according to educational methods of hand washing. The subjects were ten children aged three to five. The analyses of the microbiological effect were made before band washing education, after one-week video demonstrations of hand washing education, and after one-week video demonstrations of hand washing education combined with practice. The results were as follows. Total plate count, filamentous fungi, coliform, and Staphylocuccus aureus were detected from children's hands just before band washing education. According to the two-week hand washing education, such education was found effective in keeping the children's hands clean and safe. In conclusion, repeated and more consistent training of band washing would be important for children, especially aged three to five because most of the habits and behavior patterns were developed in these age groups and the effects were persistent during their future life.

• Korean Journal of Soil Science and Fertilizer
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• v.37 no.2
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• pp.124-130
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• 2004

This study was carried out to evaluate the effects of condensed molasses soluble (CMS) treatment on the mineralization of N, chemical properties and soil microbial population under the incubation condition with unsaturated water content during the 7 weeks at $25^{\circ}C$ in the different levels of CMS application. The results indicated that the total nitrogen content of soil was increased with increasing application rate of CMS and this trend was maintained up to 7 weeks. With CMS treatment content of $NH_4-N$ was gradually decreased. However, the content of $NO_3-N$ in the soil was gradually increased with incubation time due to the nitrification under the unsturated water condition. The CMS treatment increased the microbial populations such as bacteria, actinomycetes and fungi, which may be due to the availability of more nutrients such as amino acids, sugars and other minor elements from CMS. The pH of soil was found to be reduced by the addition of CMS, Whereas, electrical conduvtivity of soil was correspondingly increased with increasing application rate of CMS.

• Microbiology and Biotechnology Letters
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• v.43 no.2
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• pp.142-149
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• 2015

Bioaerosols are comprised of particles 0.02-100 μm in size that originate in natural and artificial environments, and as a result of human activities. They consist of microorganisms including viruses, bacteria, fungi, and protozoa; fungal spores; microbial toxins; pollen; plant or animal material; expectorated liquid from humans; and glucans (peptidoglycan and β-glucan). Bioaerosols can cause respiratory and other diseases in humans and animals. In this study, bioaerosol samples acquired from agricultural sources, livestock, a sewage treatment plant, a beach, and a pristine area were analyzed to identify and phylogenetically characterize culturable microorganisms. The isolated bacteria exhibited regional differences, with different species dominating. However, Bacillus cereus was isolated in all samples, with a total of 31 strains isolated from all areas, and Acinetobacter baumannii was isolated from an indoor poultry farm. In addition, bacteria determined to be of novel genus or species of the genera Domibacillus, Chryceobacterium, Nocardioides and family Comamonadaceae were isolated from the agricultural, livestock and beach environments.

• Korean Journal of Environmental Agriculture
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• v.32 no.2
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• pp.95-101
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• 2013

BACKGROUND: Rice (Oryza sativa) is the most important staple food of over half the world's population. This study was conducted to evaluate the possible impact of transgenic rice cultivation on the soil microbial community. METHODS AND RESULTS: Microorganisms were isolated from the rhizosphere of GM and non-GM rice cultivation soils. Microbial community was identified based on the culture-dependent and molecular biology methods. The total numbers of bacteria, fungi, and actinomycete in the rhizosphere soils cultivated with GM and non-GM rice were similar to each other, and there was no significant difference between GM and non-GM rice. Dominant bacterial phyla in the rhizosphere soils cultivated with GM and non-GM rice were Actinobacteria, Firmicutes, and Proteobacteria. The microbial communities in GM and non-GM rice cultivated soils were characterized using the denaturing gradient gel electrophoresis (DGGE). The DGGE profiles showed similar patterns, but didn't show significant difference to each other. DNAs were isolated from soils cultivating GM and non-GM rice and analyzed for persistence of inserted gene in the soil by using PCR. The PCR analysis revealed that there were no amplified protox gene in soil DNA. CONCLUSION(S): These data suggest that transgenic rice does not have a significant impact on soil microbial communities, although continued research may be necessary.

• The Korean Journal of Pesticide Science
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• v.5 no.4
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• pp.33-39
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• 2001

An isolate of the indigenous fungus Pythium myriotylum was isolated from Monochoria vaginalis in Yusung, Korea in year 2000 and evaluated potential as a biocontrol agent in laboratory and greenhouse. P. myriotylum MD2 grew in a wide range of temperature regimes and the optimal growth temperature was $35^{\circ}C$. The fungus was highly pathogenic to Monochoria vaginalis at 30 to $35^{\circ}C$. Several weeds such as Rotala, indica, Lindernia procumbens, Ludwigia prostrata, Cyperus difformis, Scirpus juncoides, Aneilema keisak were also susceptible to the fungus, but Echinochloa crus-galli was not. The fungus affected the growth of rice seed germinated, but not to rice seedlings of 1- to 3-leaf stage. A total of 12 rice cultivars (3- to 4-leaf stage) tested showed no disease symptoms when inoculated with the fungus. Eleven crops, including Chinese cabbage, corn, soybean except wheat were immune to the infection of the fungi. These data suggest that P. myriotylum MD2 has a potential as a mycoherbicide to control weeds in paddy fields.

• Journal of Conservation Science
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• v.36 no.2
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• pp.93-102
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• 2020

A lichen is a complex microorganism comprising fungi and algae. Various lichens are commonly found in cultural heritage and are reportedly related to weathering. Lichens are commonly studied in Europe; however, few reports exist on lichens in Korean cultural heritage. The present study was conducted as part of the Korean National Arboretum's "A study on the Fungus and Lichen." We report the lichen diversity found at the Placenta Chambers of King Sejong's Sons, Seongju. A total of 65 lichens were collected from 19 placenta chambers and one memorial stone. We identified 40 species belonging to 10 genera, 17 families, and 23 orders. Morphological identification revealed that foliose lichens in the form of leaves(24, 36.9%) and crustose lichens in the form of crust(24, 36.9%) were distributed at a higher percentage than that of fruticose lichen in the form of branches(17, 26.2%). Xanthoparmelia coreana(foliose lichen) and Lepraria sp.(crustose lichen) were the most collected lichens and were distributed on 19 chambers. In addition, Clodonia, a fruticose lichen, had the highest species diversity with eight species. The highest species diversity of lichens was identified on the chamber of Prince Kyeyang(16 lichens), whereas the chamber of Prince Geumsung had the lowest species diversity(five lichens). This study will be used as primary data for the study of distribution of lichen diversity in Korean cultural heritage.

• The Korean Journal of Mycology
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• v.26 no.2 s.85
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• pp.163-172
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• 1998

Thirty six strains of Pleurotus spp., from world-wide nations, were examined for interspecific isozyme variation. A comparison of isozymes in mycelial extracts of the fungal genus Pleurotus was made by polyacrylamide gel isoelectric focusing. A total of one hundred and sixty six bands was resolved from six isozymes. A cluster analysis was done based on the zymograms for esterase, glucosephosphate isomerase, leucine aminopeptidase, malate dehydrogenase, peroxidase, and phosphoglucomutase. From the isozyme analysis, esterase showed higher degree of variability, while it was observed less variability for the enzymes such as glucosephosphate isomerase, malate dehydrogenase, and phosphoglucomutase. The species P. ostreatus, whose taxon is controversial, was discriminated from P. pulmonarius, while P. florida was classified as a distinct taxon. The clustering of P. sapidus and P. spodoleucus strains appeared to be more difficult. It was found that some strains were included to another cluster based on electrophoretic banding patterns. These results show that this lack of congruence among data sets may help explain the taxonomic difficulty within the genus Pleurotus. A dendrogram of genetic similarities was presented, and applications of isozyme data to the systematics of these commercially important fungi was discussed.

• Korean Journal of Soil Science and Fertilizer
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• v.45 no.5
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• pp.829-835
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• 2012

The cultivation of genetically modified (GM) crops has increased due to their economic and agronomic advantages. Before commercialization of GM crops, however, we must assess the potential risks of GM crops on human health and environment. The aim of this study was to investigate the possible impact of Bt rice on the soil microbial community. Microbial communities were isolated from the rhizosphere soil cultivated with Bt rice and Nakdong, parental cultivar and were subjected to be analyzed using both culture-dependent and molecular methods. The total counts of bacteria, fungi, and actinomycetes in the rhizosphere of transgenic and conventional rice were not significantly different. Denaturing gradient gel electrophoresis (DGGE) analysis of PCR-amplified 16S rRNA genes revealed that the bacterial community structures during cultural periods were very similar each other. Analysis of dominant isolates in the rhizosphere cultivated with Bt and Nakdong rice showed that the dominant isolates from the soil of Bt rice and Nakdong belonged to the Proteobacteria, Cloroflexi, Actinobacteria, Firmicutes, and Acidobacteria. These results indicate that the Bt rice has no significant impact on the soil microbial communities during cultivation period. Further study remains to be investigated whether the residue of Bt rice effect on the soil environment.