• Journal of the Korean Institute of Landscape Architecture
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• v.28 no.4
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• pp.1-8
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• 2000

This study is conducted to evaluate the effects of root restriction on growth of maple(Acer palmatum Thumb.). Tow types of container such as clay pot(CP), root control bag(RCB) were used to restrict maple's root and each type of container was divided into 5 sizes. The containers with plants were buried just below the soil level and maples planted directly in the soil (nonrestricted root treatment) were included as comparison. Data were collected on dry weight of leaf, trunk, thick root, rootlet and soil water potential. We have analyzed, simple linear regression, Pearson's Correlation analysis, Duncan's multiple rang test, and Covariance Analysis using SAS statistical software. The results of analysis based on these data are as follows; 1. Total dry weight of maple in CP was significantly larger than in RCB. 2. Difference in growth reduction by the kinds of containers was induced by different hydraulic diffusion ratios between container and soil. Difference in growth reduction by the size of container was induced by the difference density of rootlet and soil moisture contents in the container. 4. Commercial products of root control of root control bag appeared not proper for countries in which fluctuation of rainfall is severe. Because maples in RCB were restricted by excess soil water in the rainy season, or by lack of soil water in the dray season.

• Restorative Dentistry and Endodontics
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• v.20 no.2
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• pp.577-609
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• 1995

Bacteria have been regarded as one of the most important factors in pulpal and periapical diseases. Streptococci are frequently isolated facultative anaerobes in infected root canals. Recently molecular biological techniques have been rapidly progressed. This study was designed to apply the molecular biological tools to the identification and classification of streptococci in the endodontic microbiology. Streptococci isolated from infected root canals were identified with both Vitek Systems and API 20 STREP. Identification results were somewhat different in several strains of streptococci. Eighteen streptococci and enterococcal was difficult so to digest plasmid DNA using Hind III and EcoRI to differentiate strains by restriction enzyme analysis of plasmid DNA. 16S rDNA of chromosome was amplified by polymerase chain reaction(PCR) and then restricition fragment length polymorphism(RFLP) using several restriction enzymes was observed. The molecular mass of 16S rDNA of chromosomal DNA was approximately 1.4kb. There were three to five RFLP patterns using eight restriction enzymes. RFLP patterns digested with CfoI which recognizes four base sequences were identical in all stains. Hind III which recognizes six base sequences could not digest the 16S rDNA. Restriction enzymes which recognize five base sequences were suitable for RFLP pattern analysis. At least three different restriction enzymes were needed to compare each strains. 16S rDNA PCR-RFLP was simple and rapid to differentiate and classify strains and could be used in the epidemiological study of root canal infections.

• Horticultural Science & Technology
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• v.33 no.4
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• pp.511-517
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• 2015

This research was conducted to evaluate the influence of root restriction materials and media on the growth of runner plantlets of 'Seolhyang' strawberry in a nursery field. To achieve this, the influence of three kinds of root media on the growth of runner plantlets was monitored when polyethylene film was used as the root restriction material. In addition, the influence of various root restriction materials (RRS) such as transparent polyethylene film (PE), non-woven fabric (NF), perforated polyethylene film (PP), and root proofing sheet (RPS) on the changes in volumetric water content (VWC) and temperature of root media as well as growth of runner plantlet were investigated when expanded rice hull (ERH) was used as the root medium. In the comparison of root media, growth parameters such as leaf area and crown thickness at 20 d after fixation as well as crown thickness and fresh weights of root and above-ground tissue at 40 d after runner plantlet fixation were higher in the ERH treatment than in sandy loam and loamy sand. When the influence of RRS was compared, the VWC of ERH was 55% just after irrigation, but decreased to 26% at just before irrigation. Ranges of the VWC as influenced by irrigation cycle were 16 to 10% in the PP and less than 10% in the NF and RPS. The soil temperature in the PE treatment was around $1^{\circ}C$ lower than in NF, PP, and RPS. The differences between day and night temperatures were also smaller in the PE treatment rather than those in NF, PP, and RPS. The growths of runner plantlet 50 d after fixation showed that plant heights as well as fresh weights of root and above-ground tissue were higher in the PE treatment than in NF, PP, and RPS. NF and PP did not effectively restrict roots inside the medium and the roots of runner plantlets penetrated through the root restriction materials resulting in the formation of root system below the restriction materials. The above results indicate that ERH is more effective than sandy loam or loamy sand as root medium. PE rather than NF, PP, or RPS as root restriction material resulted in better growth of runner plantlets in propagation of 'Seolhyang' strawberry. The results of this research will be used for production of high quality runner plantlets in strawberry propagation.

• Journal of Ginseng Research
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• v.14 no.2
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• pp.310-316
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• 1990

This study was focused on the characterization of mitochondrial DNA (mtDNA) for molecular 9enetical approach of energy Production related mechanism in Panax ginseng. The simple and efficient method of mtDNA isolation from ginseng has been developed by modification of recently advanced methods. This procedure can successfully apply to mtDNA isolation of several plants. mtDNA of etiolated shoot and one-year root were digested with restriction endonucleases, but that of 6-year root not. Any difference was not observed in the restriction endonuclease digestion patterns among the ginseng variants. Molecular size of ginseng mtDNA was estimated at least 159 kb by the restriction endonuclease fragment analysis. The 4.5 kb extra band at the lane of EcoRII treatment could be observed in restriction patterns digested with the methylation sensitive endonucleases, BstN I and EcoRII. For construction of mitochondrial genomic library of ginseng, mtDNA was partially digested with EcoRl, and packaged with EMBL4 phage vector. Genomic library was screened and purified for further research including restriction mapping of ginseng mtDNA, and cloning of the genes. The gene of ATP synthase A subunit was cloned from the purified EMBL4 library clone No. 16. Now, clone No. 16 is subcloned for structure gene sequence analysis.

• Journal of Bio-Environment Control
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• v.8 no.1
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• pp.36-41
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• 1999

This study was carried out to investigate the effect of root zone restriction on yield and quality of muskmelon. Three cultivation methods, isolated bench, root zone restriction sheet(RZR sheet) and conventional soil culture, were compared from April 19th to July 17th. Soil temperature was higher at isolated bench and the growth of melon was accelerated at isolated bench compared to soil culture or RZR sheet. Fruit size was bigger in order of soil culture, isolated bench and RZR sheet, while sugar content and net shape were greatest at isolated bench, and the percentage of wilted plant was 3.3% at isolated bench, 25.0% at RZR sheet and 26.7% at soil culture. Therefore, marketable yield was higher at isolated bench compared to conventional soil culture.

• Journal of Environmental Science International
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• v.25 no.3
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• pp.337-343
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• 2016

The present study aimed to determine the influence of various root restriction media on seedling quality and early growth of strawberry after transplanting. The root activity of the seedlings, measured 20 days after fixation, was considerably higher (0.096, 0.090, and $0.063mg{\cdot}g^{-1}{\cdot}h^{-1}$ at 420, 450, and 480 nm, respectively) in expanded rice hull (ERH) treatment than in the sandy loam and loamy sand treatments. The volumetric water content (VWC) of the root media tested across 3 irrigation regimes (15 d, 30 d, 45 d) in the nursery field was highest in sandy loam (65.0-66.8%), followed by 59.4-61.3% in loamy sand and 38.6-45.3% in ERH. When growth parameters of runner plantlets were compared, ERH treatment was found to result in the highest crown thickness and fresh weights of root and above-ground parts. This had a favorable influence on above-ground tissue growth after transplanting to plastic house soil. As mentioned above, ERH treatment resulted in the highest seedling quality and early growth after transplanting. The results of this study would serve as useful on-site data for the production of high-quality strawberry seedlings.

• Proceedings of the Ginseng society Conference
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• 1990.06a
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• pp.168-174
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• 1990

This study was focused on the characterization of mitochondrial DNA (mtDNA) for molecular genetically approach of energy Production related mechanism in Panax Ein.fend. The simple and efficient method of mtDNA isolation from ginseng has been developed by modification of recently advanced methods. This procedure can successfully apply to mtDNA isolation of several plants. MtDNA of etiolated shoot and one-year root were digested with restriction endonucleases, but that of 6-year root not Any difference was not observed in the restriction endonuclease digestion patterns among the ginseng variants. Molecular size of ginseng mtDNA was estimated at least 159 kb by the restriction endonuclease fragment analysis. The 4.5 kb extra band at the lane of EcoRll treatment could be observed in restriction patterns digested with the methylation sensitive endonucleases, BstN 1 and EcoRll. For construction of mitochondrial genomic library of ginseng, mtDNA was partially digested with EcoRl, and packaged with EMBL4 phage vector Genomic library was screened and purified for further research including restricttion mapping of ginseng mtDNA, and cloning of the genes. The gene of ATP synthase A subunit was cloned koto the purified EMBL4 library clone No. 16. Now, clone No. 16 is subcloned for structure gene sequence analysis.

• Restorative Dentistry and Endodontics
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• v.22 no.1
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• pp.413-427
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• 1997

Porphyromonas endodontalis and Prevotella intermedia are black-pigmented anaerobic gram negative rods which have been isolated from infected root canals and submucous abscesses of endodontic origin. And they are associated with clinical symptoms such as pain, percussion, and foul odor. It has been reported that there are 3 serotypes according to capsule membrane in P. endodontalis and 2 DNA homology groups and 3 serotypes in P. intermedia, but there is no data available regarding genetic diversity for the species P. endodontalis and P. intermedia. The purpose of this study is to investigate genetic diversities between individual strains of P. endodontalis and P. intermedia which are indistinguishable by serotyping and biotyping using bacterial DNA restriction endonuclease analysis. 45 teeth with at least one clinical symptoms, with single canal, and with pulp necrosis were sampled. For sampling bacteria, access cavity was prepared after disinfecting tooth and its surroundings. Then the paper point was inserted to the apex of the canal, leave there for 15 seconds, and finally it was placed into PRAS Ringer's solution and PBS solution. P. endodontalis and P. intermedia were identified by biochemical test and IIF after subculturing black and brown colonies which were produced after 7 days of incubation on BAP in anaerobic chamber. P. endodontalis and P. intermedia strains were grown in BHI broth and whole genomic DNA was extracted by phenol-chloroform extraction technique and digested by restriction endonuclease, Eco RI and Pst I. The resulting DNA fragments were separated by agarose gel electrophoresis, stained with EtBr and photographed under UV light. The results were as follows : 1. In both P. endodontalis and P. intermedia, different serotypes could be found within a root canal of same patient. 2. There were obvious genetic heterogeneity within a patient and within a serotype in both P. endodontalis and P. intermedia. 3. P. endodontalis serotype c, isolated from different patients, exhibited limited genotypic diversity.

• Journal of the Korean Society for Precision Engineering
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• v.16 no.10
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• pp.187-193
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• 1999

Dimensional difference by welding deformation is usually occurred at steel bridge manufacturting or multi-pass welding used at joining of thick plates. Be this, root gap out of standard is frequently developed at butt weld joints. For example, although standard root gap below 6mm at butt weld joints of plates under 15mm thickness, maximum 30mm root opening is developed at the weld field. At this case, 24mm parts out of standard is generally built up. But, there are no accumulated data and restriction about this built up welding pars. In this study, therefore, the accumulation of data for built up parts and the verification of the mechanical properties of weld part as root gap is performed. It is included that tensile, bending, impact, hardness test and microstructural review for each welding specimen of 0mm, 6mm, 30mm root opening.

• Horticultural Science & Technology
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• v.28 no.3
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• pp.415-422
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• 2010

Two leaf lettuces, chicory, endive, edible chrysanthemum, and pak-choi were hydroponically cultured under root restricted conditions in a deep flow technique system and their growth and nutritional values were investigated. Cylindrical plastic tubes with 100 mm height and diameters of 20, 25 or 30 mm were used for root restriction. Growth of all species was retarded by 25-95% as the roots zone was restricted. Pak-choi and edible chrysanthemum showed greater reduction in growth as compared with chicory and endive. Percent dry matter, C/N ratio, and contents of total ascorbic acid and total anthocyanin increased in the root restricted treatments. Contents of P and K decreased in the root restricted treatments, while contents of Mg, Fe, Mn, and Zn were not consistent among the tested species. Optimized root volumes to improve the nutritional values and to reduce the growth retardation varied depending on species of leafy vegetables. Tubes of ${\Phi}25mm{\times}100mm$ and ${\Phi}30mm{\times}100mm$ were suitable for chicory, endive and lettuce, and edible chrysanthemum and pak-choi, respectively. Results indicate that nutritional values of hydroponically-cultured leafy vegetables can be improved by root restriction.