• Journal of Korean Society of Forest Science
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• v.30 no.1
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• pp.50-60
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• 1976

For finding out the proper method of developing Buxus koreana var. insularis, this study was carried out in Pokil-Do, Wan-Do, Chonnam, in 1975. The ecology, morphology and characteristics of the plant were mainly investigated and analyzed. The results are summarized as follows; 1. The small islands of the southern sea of Korea; Pokil-Do, Chin-Do and So-Huk-San-Do, turn out to be the site of the natural communities of B. koreana var. insularis. 2. The growth of the plant is fairly good in the acid soil of these islands. 3. This vegetation of composed as the three-layered communities, these communities consit of Camellia, Buxus and Cares. 4. The plant is a board leaved evergreen shrub that is tolerant to shade and native to the temperate zone. 5. The size of the leaves, fruits and seeds is slightly larger than those of B. koreans. 6. As fruiting and germination of the seeds are favorable. it is easy for us to make a number of seedlings. 7. The proper times for sowing and harvesting the seeds are around the middle of July and August, respectively. 8. The seedlings is difficult to grow in the naked ground because the germinated seeds are seriously damaged by frost. 9. The plant growth per annum is about 8 to 10cm in height, 1.5mm in diameter. It is graceful looking as the branches and leaves as of the dense foliage type 10. It is possible to develop the plant in many ways, such as; ornamental plant, bee plant, sculptural and industrial materials.

• Journal of The Korean Society of Grassland and Forage Science
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• v.22 no.4
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• pp.241-246
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• 2002

Rye-hairy vetch mixture would be recommended fur produce higher yield and conserving soil environment. This experiment was conducted to investigate the effect of planting and harvest dates on quality and productivity of rye-hairy vetch mixture. Plant height of rye and hairy vetch was increased with delayed harvest dates, but it found that there was on significant difference among seeding dates. The dry matter(DM) content was increased with delayed harvest dates, and it showed 30% DM in mid-May. Crude protein(CP) content was decreased sharply from 17~18% in heading stage to 9~10% in flowering stage. The content of ADF(Acid detergent fiber) and NDF(Neutral detergent fiber) were increased with delayed harvest date, but IVDMD(In vitro dry matter digestibility) and TDN(Total digestible nutrient) were decreased. The change of dry matter yield was affected significantly by harvest date but was not by seeding time. The results of this experiments indicated that harvest in late-April would be recommended to produce the highest yield and quality if it is considered to cultivate com fur silage. Harvest in mid-May would be recommendable with the cultivation of early maturity silage corn or sorghum $\times$ sudangrass hybrids.

• Journal of Plant Biotechnology
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• v.42 no.4
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• pp.336-341
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• 2015

Blueberry (Vaccinium spp.) is a bush that grows well at special cultural environments such as acid soil, high organic matter content, and a good drainage and aeration compared to other general crops. Blueberries are well known to contain high amounts of anthocyanins and phenolic compounds, resulting in high antioxidant activity that provides health benefits, and expanding the cultivation areas and consumer's demand in the worldwide. However, the full genome of blueberry has not been announced until now. Furthermore, the genomic analysis and transcriptome approaches are not so popular compare to major crops such as orange, apple, and grape. The aim of the review about blueberry genomic research is to establish the platform for setting blueberry breeding target, increasing proficiency of blueberry research, and making the practical cultivation techniques in Korea. The main topics in the blueberry genomic research including transcriptome, genetic mapping, and various markers are related with cold hardiness, chilling requirement, hot tolerance, anthocyanin content, and flavonoid synthesis pathway on various tissues like flower bud, leaf bud, shoot, root, and berry fruit. The review of the current status of blueberry genomic research will provide basic information to the breeders and researchers and will contribute to development of blueberry industry with sustainable productions and increase of blueberry consumption as new profitable crops in Korea.

• Journal of Plant Biotechnology
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• v.42 no.4
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• pp.396-400
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• 2015

To investigate the optimal conditions for shoot organogenesis in Astragalus sinicus L., hypocotyl explants were cultured in Murashige & Skoog's (MS) medium supplemented with 0.1, 1.0, 2.0, or 4.0 mg/L 2,4-dichlorophenoxy acetic acid (2,4-D) for 6 weeks. 2,4-D concentration significantly effected morphogenesis: some produced calli with adventitious shoots and roots, some produced calli with adventitious roots, some produced only calli, and some produced deep-brownish calli with roots. The formation of calli with shoots and/or roots was observed at lower levels of 2,4-D, whereas calli without shoots or with deep-brownish roots were formed after treatment with higher levels of 2,4-D. Also, a shoot organogenesis ability of callus clones was observed after treatment with medium with 0.1 or 1.0 mg/L 2,4-D grown in MS medium with combinations of benzyl adenine (BA) and 2,4-D for 4 weeks. Medium with a combination of BA and 2,4-D was effective for shoot formation, whereas root organogenesis from calli decreased. The greatest amount of shoot formation was obtained when calli were cultured in MS medium containing 1.0 mg/L 2,4-D and 0.5 mg/L BA. Upon shoot transfer into 1/2 MS basal medium, plantlets developed, and the plantlets grew well in soil in a greenhouse.

• Microbiology and Biotechnology Letters
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• v.6 no.1
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• pp.41-46
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• 1978

Piscicidal substance produced by Streptomyces sp. isolated from soil was toxic against various kinds of fish. After extraction with CH$Cl_3$ from the culture medium, the substance was purified by avicel column chromatography. In order to test toxicity, various kinds of fish were subjected to the acqueous solution of 100 us of the substance per liter of water. Generally, the substance was toxic to most fish, but Macropodus chinenes and Misgurnus mizolepis are resistant to the substance than Gobius similis and Pseudorasbora parva. The substance was stable at pH range, 3.0 to 7.0, but labile at alkaline pH, and to heat as well. Succinic dehydrogenase on most of tissue cell of Cyprinus carpio was inhibited by this substance strongly, but spinal cord was not inhibited. By addition of Cu and Pb salts to the culture medium, piscicidal substance producibility was activated.

• Economic and Environmental Geology
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• v.36 no.2
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• pp.123-131
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• 2003

Geophysical surveys(electrical resistivity, self-potential, seismic refraction, GPR) were conducted to investigate the physical properties of the subsurface, and to delineate the flow channel of leachate from a AMD(acid mine drainage), buried rock wastes and tailings, and drainage pipes at an abandoned mine(Kwangyang mine). Especially in rainy season the sites appear to be abundant in AMD leachate, characterized by electrical conductivities of 0.98-1.10 ms/S. Electrical resistivity sections indicate that the leachate flows running in two directions at southern part rise up through the narrow fracture zones at the central part and contaminates the surrounding soil and stream. Such schematic features at the anomalous zone are well correlated with negative peaks in self-potential data, the limited penetration depth in GPR data and low velocity zone in seismic refraction data. Shallow high-resistivity zone is associated with the buried rock wastes which cause the diffractions in GPR image. In addition, the events at depth of approximately 1-1.25 m in GPR sections must be the metal pipes through which AMD is drained off to the inner bay.

• Journal of Microbiology and Biotechnology
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• v.8 no.2
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• pp.171-177
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• 1998

The strain A49, which produces a new type of extracellular polysaccharide was isolated from soil samples. From morphological, physiological and biochemical tests, the strain A49 was identified as a Bacillus polymyxa and named Bacillus polymyxa A49. Bacillus polymyxa A49 was found to produce a highly viscous extracellular polysaccharide when grown aerobically in a medium containing glucose as the sole source of carbon. The polysaccharide (A49 POL) showed a homogeneous pattern on gel permeation chromatography (GPC) and its molecular weight was estimated to be about 1.6 mega dalton (mDa). The FT-IR spectrum of A49-POL revealed typical characteristics of polysaccharides. As a result of investigations with HPLC and carbozole assay, A49-POL was found to consist of L-fucose, D-galactose, D-glucose, D-mannose, and D-glucuronic acid, with the molar ratio of these sugars being approximately 1:2:7:50:12. Rheological analysis of A49 POL revealed that it is pseudoplastic and has a higher apparent viscosity at dilute concentrations than does xanthan gum. The consistancy factor of A49 POL was found to be higher, and the flow index of A49 POL lower, than xanthan gum. Its apparent viscosity was comparatively unstable at various temperatures. the A49 POL showed the highest apparent viscosity at pH 3. When salts were added to A49 POL solution, the solution was compatible with up to 10% KCl, 35% NaCl, 55% $CaCl_2$, 55% $MgCl_2$, 55% $K_2HPO_4$, and 110% $Ca({NO_3})_2$, respectively.

• Microbiology and Biotechnology Letters
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• v.10 no.2
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• pp.133-144
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• 1982

The distribution of acid phosphatase activity was investigated with 141 microorganisms from the type culture collection of Chong Kun Dang laboratory and the 41 strains isolated from natural sources. The phytase activity was detected mainly with fungal strains. A fungus isolated from soil and identified as Aspergillus niger had shown the highest phytase activity. The environmental conditions for the enzyme formation by the isolate and some properties of the enzyme were also studied. The results obtained were as follows: (1) The highest phytase production was observed when the fungus was cultivated at 28$^{\circ}C$ for 5 days in the corn starch based medium using the cells incubated at 34$^{\circ}C$ for 3 days as a seed. (2) The optimal initial pH of the culture medium was found to around 2 for the formation of phytase. (3) Sucrose was proved to be one of the most effective carbon sources tested for the enzyme production. (4) As an inorganic nitrogen source, potassium nitrate was found to give a good result in the production of phytase. (5) Synthesis of phytase was significantly increased by the supplement with 0.2 % corn steep liquor to the basal medium as an organic nitrogen source. (6) At the concentration of 40-80 mg inorganic phosphate per liter of the culture medium, the enzyme formation revealed the highest level. But as the phosphate was increased above this optimum concentration the phytase activity was drastically decreased although the cell density showed to be still increasing

• Microbiology and Biotechnology Letters
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• v.47 no.4
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• pp.603-613
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• 2019

This study was carried out to examine the antagonistic effect against phytopathogenic fungi of isolated strains from soil samples collected from Busan, Changwon, and Jeju Island: Botrytis cinerea, Colletotrichum acutatum, Corynespora cassiicola, Fusarium sp., Rhizoctonia solani, Phytophthora capsici, and Sclerotinia sclerotiorum. According to results of our studies, isolated strains showed an antagonistic effect against phytopathogenic fungi. Such an antagonistic effect against phytopathogenic fungi is seen due to the production of siderophores, antibiotic substances, and extracellular amylase, cellulase, protease, and xylanase enzyme activities. Extracellular enzymes produced by isolated strains were significant, given that they inhibited the growth of phytopathogenic fungi by causing bacteriolysis of the cell wall of plant pathogenic fungi. This is essential to break down the cell wall of plant pathogenic fungi and thus help plant growth by converting macromolecules, which cannot be used by the plant for growth, into small molecules. In addition, they are putative candidates as biological agents to promote plant growth and inhibit growth of phytopathogenic fungi through nitrogen fixation, indole-3-acetic acid production, siderophore production, and extracellular enzyme activity. Therefore, this study suggests the possibility of using Bacillus subtilis ANGa5, Bacillus aerius ANGa25, and Bacillus methylotrophicus ANGa27 as new biological agents, and it is considered that further studies are necessary to prove their effect as novel biological agents by standardization of formulation and optimization of selected effective microorganisms, determination of their preservation period, and crop cultivation tests.

• Journal of Korean Society of Environmental Engineers
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• v.29 no.7
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• pp.793-800
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• 2007

A total of 48 samples of street dust were collected in Daegu area during April and May 2006, were sieved below 100 ${\mu}m$, and analysed by ICP for the analysis of 14 elements after an acid extraction. Results obtained from the source assessment of trace elements using enrichment factor showed that Ca, Fe, K, Mg, Mn, Na and V were influenced by natural sources such as soil and dust, while Cd, Cr, Cu, Ni, Pb and Zn were influenced by urban anthropogenic sources such as fuel combustion and waste incineration. The measured values were remarkably higher in components from natural sources than in components from urban anthropogenic sources. The concentrations of trace elements in Daegu area were generally higher than in other foreign cities. Samples originated from industrial and commercial areas had higher concentrations of trace elements and pollution indices of heavy metals than those from residential and green areas. The correlation analysis among trace elements indicated that the correlations among components from urban anthropogenic sources were much significant, while those among components from natural sources were less correlated. In addition there were significant correlations between traffic density and components from urban anthropogenic sources.