• KOREAN JOURNAL OF CROP SCIENCE
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• v.40 no.5
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• pp.619-628
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• 1995

Crude aqueous extracts from dried leaves, stems, roots, and flowers from both field grown and greenhouse grown alfalfa plants inhibited alfalfa seed germination and seedling growth. The degree of inhibition was greater in the field grown plant extracts. Flowers extract of field grown plant most inhibited alfalfa germination and seedling growth. In the concentration study, the highest concentration of extract (9.0%, w/v) significantly inhibited total alfalfa seed germination by 50% as compared to control. In partitioning study using pot hydroponic culture of plant biomass into leaves, stems, root, LAR products of LWR and SLA exhibited significant variation among four species. This result support that the inhibitory effect of autotoxic substances presenting in alfalfa tissue may be possible interference with the patitioning of biomass into leaf component relative to the total biomass produced by the alfalfa plant. Toxicity of extract was not reduced by adding activated charcoal, Dowex-50W, amberlite to the extract. Toxic substances existing in most plant tissues but mainly above ground foliage are water soluble and stable and may persist in old alfalfa fields. Thus, it is recommended to remove as much as possible of the above growth parts, especially vegetative stage, before one tries to re-establish alfalfa in former field of alfalfa.

• The Korean Journal of Mycology
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• v.24 no.2 s.77
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• pp.93-103
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• 1996

In order to find out effect on the inorganic and organic compounds as a soil amendment to control Fusarium wilt of cucumber caused by Fusarium oxysporum f. sp. cucumerinum, this study was conducted during the last two years from 1993 to 1995. According to add 14 inorganic chemicals (1%, w/v) including $Al_2(SO_4)_3$ individually in vitro, these chemicals were confirmed their suppression, and especially Alum, CaO and $Al_2(SO_4)_3$ suppressed not only $20.9{\sim}25.0$ percent on mycelial growth of the fungus, but also inhibited $72.8{\sim}97%$ on conidial germination. $Ca(NO_3)_2$ suppressed mycelial growth only, while KCl, $K_2SO_4,\;NH_4NO_3$, and Urea suppressed conidial germination. The 7 chemicals were finally seleced. Composted pine bark (CPB) suppressed definely more than 90% on conidial germination in the different extract concentration (2,5 and 10%), although mycelial growth on extract medium of CPB and milled alfalfa leaves (MAL) were not remarkable. The antagonist Trichoderma sp. (Tr-3) mixed with an amended soil (1%, w/w) containing composted pine bark showed a good mycelial growth to compete the causal fungus. And the antagonist Pseudomonas sp. (7-1-3) was also confirmed its antagonistic ability with culture filterate. It is known that a CPB soil amendment mixed with the two antagonists (1%, w/w) controlled almost completely Fusarium wilt of cucumber in greenhouse pots and a field experiment. It is therefore expected that biocontrol on Fusarium wilt of cucumber by a soil amendment can be applied to farmmer's fields.

• The Korean Journal of Mycology
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• v.42 no.3
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• pp.225-230
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• 2014

Sclerotinia sclerotiorum, a plant pathogenic fungus, can cause serious yield and quality losses in the winter lettuce field. For biological control of S. sclerotiorum, soil-born microorganisms that inhibit the mycelia growth of S. sclerotiorum and Fusarium oxysporum were isolated from diseased soil. Among the isolates, bacterial isolate, GG95, which was identified as Bacillus subtilis according to the morphological, physiological characteristics and by 16S rRNA similarity, showed the highest level of inhibitory activity. The growth conditions for B. subtilis GG95 were optimized in TSB media (pH 7) by culturing at $28^{\circ}C$ for 24 hrs. Maltose or fructose and peptone were selected as the best carbon and nitrogen sources, respectively. Greenhouse experiment was performed to test effectiveness of B. subtilis GG95 in the control sclerotinia rot. Drench application ($1{\times}10^8cfu/mL$, 3 times) of the bacterial culture broth to lettuce showed an effectiveness value of 88%, suggesting that B. subtilis GG95 would be a promising biocontrol agent for control of sclerotinia rot.

• Korean Journal of Plant Resources
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• v.21 no.4
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• pp.304-309
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• 2008

All the seeds of rape (Brassica napus) sprout vegetables were germinated within three days after seeding irrelevant to the light colors. The total fresh weight of rape sprout vegetables at 6 days after seeding have been increased when grown under green and white color lights by 0.339g/10plants and 0.339g/10plants compared with the control. The total flavonoid contents in rape sprouts were increased under red and blue lights by 72.5 and 70.9mg${\cdot}L^{-1}$. Those DPPH radical scavenging activities at 2,000mg${\cdot}L^{-1}$ were increased by 90.0 and 90.3% which were sprouted and grown under blue and white lights. Nitrite radical scavenging activity of sprouts were most decreased compared with the control when grown under the red light by 57.4mg${\cdot}L^{-1}$. And mushroom tyrosinase inhibition activity of rape sprouts was extremely increased under the green light by 22.5mg${\cdot}L^{-1}$.

• Korean Journal of Environmental Agriculture
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• v.16 no.4
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• pp.304-310
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• 1997

In greenhouse, a mixed solution of Mn-54, Co-60, Sr-85 and Cs-137 was applied to the soil of culture boxes 2 days before sowing cucumber and at 4 different times during its growth for measuring their transfer factors (TFs) for fruit and migration in soil. TFs varied with radionuclide, application time and harvest time by factor of up to about 60. Variations in TFs with application time showed different patterns among radionuclides. TFs decreased on the whole in the order of Sr-85 > Mn-54 > Co-60 > Cs-137. TFs of Mn-54, Co-60 and Cs-137 mixed with topsoil before sowing were a little higher than those for the soil-surface application made at an early growth stage while no difference in Sr-85 TF was found. After harvest, soil concentrations of the radionuclides applied at an early growth stage were examined. They decreased with increasing soil depth and 80${\sim}$99% of the radioactivity remained in the top 3cm. Soil pemeation of the radionuclides migration decreased in the order of Sr-85 > Mn-54 > Co-60 > Cs-137. The present data can be utilized in estimating radionuclide concentration in cucumber fruit, taking proper measures for its harvest and consumption and designing the best way of soil decontamination following an radioactive deposition during the cucummber growing season.

• Journal of Plant Biotechnology
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• v.47 no.1
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• pp.66-72
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• 2020

Alstroemeria plants were transformed by using an improved particle-gun-mediated transformation system. Friable embryogenic callus (FEC) induced from the leaves with axil tissues of Alstroemeria plant was used as the target tissue. Also, FEC was transformed with the bar gene was used as a selectable marker. In the case of plasmid pAHC25, 7.5% of the twice-bombarded FEC clumps showed blue foci, whereas the clumps with single bombardment showed only 2.3%. Additionally, a 90° rotation with double bombardment led to a higher frequency (6 times) of luciferase gene expression in PBL9780 than the control treatment. After 8 weeks of bombardment, more than 60 independent transgenic lines were obtained for pAHC25 and nearly 150 independent transgenic lines were obtained for PBL9780, all of which were resistant to PPT and demonstrated either GUS or luciferase activity. Regarding effect of osmotic treatment (0.2 M mannitol) with 7 different periods, the highest transient gene expression was obtained in 8 h before and 16 h after transformation in both pAHC25 and PBL9780. Compared with the control, at least three times more GUS foci and photons were observed in this treatment. With respect to different combinations of mannitol and sorbitol with 8 h before and 16 h after transformation, high numbers of transient and stable transgene expressions were observed in both 0.2 M mannitol and 0.2 M sorbitol used in the osmotic pre-culture. This combination showed the highest transformation efficiency in both pAHC25 (8.5%) and PBL9780 (14.5%). In the control treatment, only 10% of the FEC clumps produced somatic embryos. However, by using 0.2 M mannitol and 0.2 M sorbitol, the frequency of somatic embryos increased to 36.5% (pAHC25) and 22.9% (PBL9780). Of the somatic embryos produced, at least 60% germinated. Approximately 100 somatic embryos from these 210 independent transgenic lines from 2 plasmids developed into shoots, which were then transferred to the greenhouse. PCR analysis confirmed the presence of the bar gene. This is the report on the production of transgenic Alstroemeria plants by using particle bombardment with a high efficiency, thereby providing a new alternative for the transferring of gene of interests in Alstroemeria in the breeding program in the future.

• Review of Culture and Economy
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• v.17 no.2
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• pp.81-102
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• 2014

As carbon dioxide, the main greenhouse gas, is generally emitted by vehicles, the development and distribution of electric cars is important for the sustainability of environmentally-friendly tourism, especially in national parks. National parks in Korea, however, still see the use of traditional vehicles powered by internal combustion engines in the handling of visitors and the transportation of goods and staff. Such engines being the cause of environmental problems such as exhaust emission and noise pollution, the introduction of electric cars in national parks is needed. This study aims to analyze the economic value of electric cars in national parks as well as contribute to the development of the Green Transportation model in tourism destinations. The study used a logit model to estimate the willingness to pay for the introduction of electric cars in national parks. Adults over the age of twenty, with gender and age apportioned equally, were surveyed using questionnaires that included dichotomous as well as demographic questions. The findings show that the amount an individual is willing to pay for the purpose of environmental conservation is 3,948 won, while the value the national parks would derive from the use of electric cars is 56,138,130,000 won. The introduction of electric cars in national parks is expected to offer both direct and indirect benefits while helping to improving the environment of the national parks by eliminating exhaust emission and noise. This introduction would also be a response to climate change that can be taken by society as a whole.

• Korean Journal of Construction Engineering and Management
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• v.20 no.2
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• pp.53-59
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• 2019

As solve the shortage problems of storage space for exhibition facilities, the South Korean government is establishing plans to expand storage space for exhibition facilities. From a medium- to long-term perspective, an energy-efficient storage space for exhibition facility is needed to implement efficient state budget execution and achieve national greenhouse gas reduction goals. In this regard, this study analyzed the energy consumption of storage space for exhibition facilities according to the use of absorption materials. To this end, a case study was conducted on 12 storage spaces for exhibition facilities in South Korea. Compared to the storage space using the absorption material, the storage space without using the absorption material showed an increase in HVAC system operation time by 47.50% during summer periods and 58.85% in non-summer periods. In particular, the analysis found that in the case of storage for 'H' exhibition facility, the energy cost was reduced by 2,721,700 won/year after remodeling work using the absorption material. It is expected that the findings of this study can help the government and the person in charge from construction companies to construct energy-efficient storage space room for exhibition facilities.

• Korean Journal of Heritage: History & Science
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• v.46 no.2
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• pp.150-165
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• 2013

This study aims to investigate the original position, the writer of signboard handwriting and the period of Wibongmun and Joyangru in order to restore Wibongmun and Joyangru which have been designated as tangible cultural properties (有形文化財). They also have to be moved in the Gangwon Provincial Office. Wibongmun and Joyangru were established as government offices in chuncheon(春川官衙) and they were used as attached buildings in Chunceon (春川離宮) in 1890. Wibongmun was moved to Gangwon Provincial Office 5 times and Joyangru was moved twice. In order to move them back to the original place, by using the topographic map made by the Japanese Government-General in Korea, we find out Joyangru was located in the exit of Gangwon Provincial Office and greenhouse and we also figure out Wibongmun was located in the garden. While we study historical evidence on handwriting, we also find out the handwriting of Joyangmun was written by Songhaong (松下翁) Jo, Yun-Hyeong (曺允亨). Especially, Joyangru had played a role as a government office and it may be called 'Joyangru' after reconstructing 'Joyangmun' when attached buildings were established. Through this study, we found that the first period and reason of establishing Wibongmun and Joyangru was at least before 1788. Through this study, we can find the period of both and its historic meaning more clearly.

• Journal of Practical Agriculture & Fisheries Research
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• v.17 no.1
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• pp.163-179
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• 2015

The aim of this study is to investigate to which degree farmers did the crop switching and cultivar renewal as a confrontational strategy to climate change, and which problems they had in that process, and then to provide the supporting plans for them. We conducted a questionnaire survey of 15 citrus farmers of the KNCAP graduates in Jeju Island. Most of the survey respondents agreed to the climate change of Jeju Island and the subtropical climate of its coastal area. The farmers have experienced irregular weather such as abnormal high temperature, frequent rain, and droughts, resulting in the harmful insects and new weeds attack. As the climate change strategies, they are adopting a greenhouse culture system, improving a soil drainage using reorganization of planting space, making a new pest management program, and trying to switch a crop to subtropical fruits. It is expected that 50% of the survey respondents have changed their crops or will do; and 73 % of them have changed cultivar or have a plan to do. Only a few farmers directly pointed to a reason for their efforts to change the crops or to renew the cultivars as the anti-climate change strategy, however, most farmers answered the reason was to increase profitability by meeting their consumers' tastes. Presently, it is not the anti-climate change strategy but increase of profitability by meeting the consumers' needs the reason why most of the survey respondents have changed their crops or renewed the cultivars, while a few of them switched their crops to a subtropical fruit trees due to climate change. On the crop switching, they had some difficulties such as a labor shortage, availability of land, operating costs and instable income. On the cultivar renewal, also, they encountered the lack of cultivating techniques for new cultivars and the dim future for the new market. In long-term perspective, Jeju's farmers need new information and educational programs about the effect of climate change on agriculture of Jeju, and cultivation techniques for new crops and new cultivars.