• Journal of Plant Biotechnology
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• v.5 no.4
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• pp.225-231
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• 2003

The hormonal requirement suiting micropropagation of Morus alba during any season throughout the year was studied. Sprouting frequency from axillary buds of M. alba was greatly influenced by the time of explant collection, the highest value was achieved when nodal explants were collected at the end of bud dormancy period (late in March) and cultured on Murashige and Skoog (MS) medium supplemented with low concentration (0.5 mg/L) of BAP, kinetin or IBA (85-68%). In addition, they showed higher axillary bud sprouting on growth-regulators-free medium (49%) than others collected in autumn or winter and cultured on medium supplemented with various growth regulators (47-48%). Regardless of that period, young explants with greenish buds collected in summer exhibiting high sprouting frequency (66%) on MS medium supplemented with 0.5 mg/L kinetin and 0.5 mg/L GA3. Shoot multiplication via adventitious bud formation was achieved when the nodal explants were cultured on MS medium supplemented with 2 mg/L BAP and 0.2 mg/L IBA. Further multiplication via nodal explants of in vitro grown shoots was obtained on MS medium supplemented with 0.5 mglL BAP and 0.5 mg/L GA3. While half strength MS medium supplemented with low concentration (0.5 mg/L) of IBA, IAA or 2,4-D stimulated adventitious root formation, IBA was the best. After transfer the plantlets to the soil, acclimatization for three weeks was essential prerequisite for survival in high frequency (92%). Peroxidase activity is related to break of bud dormancy where maximum enzyme activity was detected when the lateral buds were induced to commence growth under field condition (early in spring) or in vitro.

• Journal of Bio-Environment Control
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• v.29 no.2
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• pp.181-188
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• 2020

This study was conducted to identify the optimal conditions for seedling growth in Veronica rotunda var. subintegra (Nakai) T.Yamaz. which a endemic plant and can be development as ornamental plants. We sowed V. rotunda var. subintegra (Nakai) T.Yamaz. seeds, and exposed the seedling was different treatment conditions. We varied soil type and fertilizer concentration, shading ratio, additional fertilizer concentration, pretreatment light exposure and collection time of seeds. We found that seedling growth was good in horticultural substrate (with no additional fertilizer), but mixed soils supplemented with fertilizer inhibited growth, regardless of the fertilizer concentration. In the 55% shading treatment, seedling growth was greater than in the non-shading treatment. High concentration addition of fertilizer (Hyponex) promoted plant growth, in terms of both plant length and fresh weight. Exposure of seeds to a red light-source prior to germination had a greater effect on seedling growth than exposure to other light sources. Seedlings exhibited better growth when grown from seed collected in 2018, rather than 2017.

• Journal of Microbiology and Biotechnology
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• v.27 no.9
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• pp.1559-1565
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• 2017

Naturally occurring ginsenoside F1 (20-O-${\beta}$-$\text\tiny{D}$-glucopyranosyl-20(S)-protopanaxatriol) is rare. Here, we produced gram-scale quantities of ginsenoside F1 from a crude protopanaxatriol saponin mixture comprised mainly of Re and Rg1 through enzyme-mediated biotransformation using recombinant ${\beta}$-glucosidase (BgpA) cloned from a soil bacterium, Terrabacter ginsenosidimutans Gsoil $3082^T$. In a systematic step-by-step process, the concentrations of substrate, enzyme, and NaCl were determined for maximal production of F1. At an optimized NaCl concentration of 200 mM, the protopanaxatriol saponin mixture (25 mg/ml) was incubated with recombinant BgpA (20 mg/ml) for 3 days in a 2.4 L reaction. Following octadecylsilyl silica gel column chromatography, 9.6 g of F1 was obtained from 60 g of substrate mixture at 95% purity, as assessed by chromatography. These results represent the first report of gram-scale F1 production via recombinant enzyme-mediated biotransformation.

• The Plant Pathology Journal
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• v.37 no.4
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• pp.315-328
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• 2021

Fusarium and Rhizoctonia genera are important pathogens of many field crops worldwide. They are constantly evolving and expanding their host range. Selecting resistant cultivars is an effective strategy to break their infection cycles. To this end, we screened a collection of Medicago truncatula accessions against Fusarium oxysporum, Fusarium solani, and Rhizoctonia solani strains isolated from different plant species. Despite the small collection, a biodiversity in the disease response of M. truncatula accessions ranging from resistant phenotypes to highly susceptible ones was observed. A17 showed relative resistance to all fungal strains with the lowest disease incidence and ratings while TN1.11 was among the susceptible accessions. As an initiation of the characterization of resistance mechanisms, the antioxidant enzymes' activities, at the early stages of infections, were compared between these contrasting accessions. Our results showed an increment of the antioxidant activities within A17 plants in leaves and roots. We also analyzed the responses of a population of recombinant inbred lines derived from the crossing of A17 and TN1.11 to the infection with the same fungal strains. The broad-sense heritability of measured traits ranged from 0.87 to 0.95, from 0.72 to 0.96, and from 0.14 to 0.85 under control, F. oxysporum, and R. solani conditions, respectively. This high estimated heritability underlines the importance of further molecular analysis of the observed resistance to identify selection markers that could be incorporated into a breeding program and thus improving soil-borne pathogens resistance in crops.

• Journal of the Korean Association of Geographic Information Studies
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• v.26 no.4
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• pp.56-66
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• 2023

Safety accidents are increasing, such as changes in groundwater levels due to construction work or natural influences, or ground cave-ins caused by soil runoff from old water supply and sewage pipes. In addition, underground facility management agencies must make efforts to improve the accuracy of underground information through continuous investigation and exploration in accordance with the Special Act on Enhanced Underground Safety Management. Accordingly, in this study, we defined the configuration of equipment and data processing method to collect 3D precise exploration underground facility information and developed 3D underground facility information collection technology to ensure accuracy of underground facilities. As a result of verifying the developed technology, the horizontal accuracy improved by an average of 6cm compared to the existing method, making it possible to acquire 3D underground facility information within the error range of the public survey work regulations.

• Journal of Drive and Control
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• v.21 no.2
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• pp.23-29
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• 2024

Potatoes are one of the world's four major crops, and domestic consumption is currently increasing in Korea. However, the mechanization rate of potatoes is very low, and especially, harvesting is the most labor-intensive task in potato production. In Korea, potato-collecting work depends on manpower, so it is necessary to develop a gathering-type harvester that can be used for processes from digging to harvesting. Therefore, in this study, a self-propelled-type potato harvester was developed, and its performance was analyzed to mechanize harvesting. The potato harvester was developed to have a crawler-type driving part with a 60 hp diesel engine and consisted of a digging part that digs potatoes from the ground, a vertical transporting part that transfers the dug potatoes to the height of the collection bag, a separating part that separates debris, such as stones and soil, and a collecting part that loads the collection box. A field test of the potato harvester was conducted, and performance was evaluated by the damage, loss, and debris mixing proportions, which were 2.5%, 2.8%, and 2.6%, respectively. The working capacity was 1.2 h/10 a. The economic analysis results showed that the cost of harvesting work could be reduced by 12.7% compared to manual harvesting.

• Journal of Radiation Industry
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• v.18 no.1
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• pp.15-21
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• 2024

The Non-Proliferation Treaty (NPT) is the basis of global efforts to prevent the spread of nuclear weapons. In Republic of Korea, safety measures are integrated with NPT approval through agreements with the International Atomic Energy Agency (IAEA) and the Safeguards Agreement. In contrast, Democratic People's Republic of Korea (DPRK), initially an NPT member, withdrew, refusing IAEA nuclear inspections. This inhibits the precise management of DPRK's nuclear facilities and limits access to related information. The Korean Peninsula, politically divided, sees DPRK in control of nuclear weapons. Although the IAEA periodically evaluates DPRK's nuclear facilities, there's a research gap in contamination and site management with nuclear activities. Recognizing the presence or absence of such activities is crucial for peaceful nuclear endeavors. This proposal suggests the number and locations for environmental sample collection using the Visual Sample Plan (VSP) software for nuclear activity analysis. VSP software is sample collection locations and quantities through statistical tests on collected data, ensuring reliability for decision-making. The proposal identifies sites and facilities for nuclear activity analysis based on IAEA safety reports, utilizing the software's embedded methods. Suggested sampling locations for undisclosed nuclear activities employ VSP's embedded techniques, including 'Show that at least some high % of the sampling area is acceptable' to confirm contamination and 'Estimate the Mean' to evaluate the average contamination level.

• Journal of Microbiology and Biotechnology
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• v.16 no.10
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• pp.1554-1560
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• 2006

A Gram-positive, aerobic or facultative anaerobic, non motile, endospore-forming bacterial strain, designated Gsoil $114^T$, was isolated from a soil sample of a ginseng field in Pocheon Province (South Korea), and was characterized taxonomically by using a polyphasic approach. It grew well on nutrient agar medium and utilized a limited number of organic substrates as sole carbon sources, including D-xylose and some other carbohydrates, but did not utilize L-amino acids and organic acids. The isolate was positive for oxidase test but negative for catalase, and negative for degradation of macromolecules such as starch, cellulose, xylan, casein, chitin, and DNA. The G+C content of the genomic DNA was 41.8 mol%. The predominant isoprenoid quinone was menaquinone 7 (MK-7). The major fatty acids were $anteiso-C_{15:0}$ (32.1%), $iso-C_{15:0}$ (30.5%), and $anteiso-C_{17:0}$ (30.2%). Comparative 16S rRNA gene sequence analysis showed that strain Gsoil $114^T$ fell within the radiation of the cluster comprising Bacillus species and joined Bacillus shackletonii LMG $18435^T$ with a bootstrap value of 95%. The highest 16S rRNA gene sequence similarities were found with Bacillus shackletonii LMG $18435^T$ (97.6%), Bacillus acidicola DSM $14745^T$ (96.9%), Bacillus sporothermodurans DSM $10599^T$ (96.5%), and Bacillus oleronius DSM $9356^T$ (96.5%). The phylogenetic distance from any other validly described species within the genus Bacillus was less than 96%. DNA-DNA hybridization experiments showed that the DNA-similarities between strain Gsoil $114^T$ and closest phylogenetic neighbors were less than 39%. On the basis of its phenotypic properties and phylogenetic distinctiveness, strain Gsoil $114^T$ (=KCTC $13944^T$=DSMZ $18134^T$) was classified in the genus Bacillus as the type strain of a novel species, for which the name Bacillus ginsengihumi sp. nov. is proposed.

• Journal of Radiation Protection and Research
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• v.41 no.1
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• pp.49-55
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• 2016

Background: For the purpose of baseline data collection and enhancement of environmental monitoring the distribution studies of $^{137}Cs$ and $^{90}Sr$ in the soil of Uljin province was performed and the relation between surface soil activities and soil properties (pH, TOC and median of the surface soil) was analyzed. Materials and Methods: For 14 spots within 10 km from the NPP surface soil samples were collected and soils for depth profile were sampled for 3 spots in April 2011. Using ${\gamma}$-ray spectrometry with HPGe detector, the concentrations of $^{137}Cs$ were determined and the concentrations of $^{90}Sr$ were measured by counting ${\beta}$-activity of $^{90}Y$ (in equilibrium with $^{90}Sr$) in a gas flow proportional counter. Results and Discussion: The concentration ranges of $^{137}Cs$ and $^{90}Sr$ were $<0.479-39.6Bq{\cdot}(kg-dry)^{-1}$ (avg. $7.51Bq{\cdot}(kg-dry)^{-1}$) and $0.209-1.85Bq{\cdot}(kg-dry)^{-1}$ (avg. $0.74Bq{\cdot}(kg-dry)^{-1}$) which were similar to the reported values from other regions in Korea. The activity ratio of $^{137}Cs$ to $^{90}Sr$ in surface soils was around 9.67, which is much bigger than the initial value of 1.75 for worldwide fallouts because of faster downward movement of $^{90}Sr$ after fallout than that of $^{137}Cs$. For depth profile studies soils were collected down to 40 cm depth for the locations of Deokgu, Hujeong and Maehwa. The $^{137}Cs$ concentration distribution of the first two showed maximum values at top soils and decreased rapidly in exponential manner, while $^{90}Sr$ showed two local maximum values for soils near top and about 30 cm depth. Through linear fittings between the $^{137}Cs$ and $^{90}Sr$ concentrations of surface soil and pH, TOC and median of the surface soil, the only probable relationship obtained was between $^{137}Cs$ and TOC (determination coefficient $R^2=0.6$). Conclusion: The concentration ranges of $^{137}Cs$ and $^{90}Sr$ in Uljin were similar to the reported values from other regions in Korea. The only probable relationship obtained between activities and soil properties was between $^{137}Cs$ and TOC.

• Journal of Korean Society of Forest Science
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• v.86 no.1
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• pp.105-111
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• 1997

Root dynamics of a pine stand at Hongcheon, Korea was assayed with two kinds of soil samplers which had been tentatively manufactured to renovate the routine soil sampler, Oakfield soil sampler. Root-mixed soil samples were collected on December of 1995, March, May, August and December of 1996 within each randomly selected 8 plots. The amount of roots collected by the two kinds of soil samplers were not significantly different at the 5% level, which indicated that the renovated sampler was more desirable to be used since the sampler showed efficiencies in time for collection and quantification than the routine sampler. The quantities of total root in 100g soils were 469mg on December of 1995, and 352mg, 473mg, 461mg, 522mg on the following March, May, August and December, respectively. That is, total amount of roots showed the smallest in Spring and reached maximum in early Winter, although the differences were not significant among each season. By the way, the alive roots and dead roots showed significant differences among season, the alive roots took about 90% from May to early December while they decreased down to some 65% from late December to March. The roots of Pinus densiflora S. et Z. took about 46% of total roots although the species comprised 70% of crown layer, and the ratio of fine-roots of the species were higher than that of other species. By the way, the dynamics of total roots and that of alive roots were quite different. Thus, the study for root dynamics such as fine roots which take a major role for mycorrhizae formation or nutrient uptake should not be inferred from the data of total root dynamics but be investigated in detail by dividing them into each class.