• KOREAN JOURNAL OF CROP SCIENCE
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• v.42 no.1
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• pp.22-32
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• 1997

This experiment was conducted to obtain information for the cultivation of Korean valerian(Valeriana lauriei var. dasycarpa Hara) which will be useful for medicinal and aromatic resources. The effect of different temperature conditions, light intensities and soil water conditions on growth, yield and component of essential oil of V. fauriei were measured at the Dankook University, Cheonan, and a study on the shading treatment was at Umsung, Chungchongbukdo, and Jinbu, Kangwondo, in 1995. V. laudei was planted at five different temperature conditions, 10, 15, 20, 25 and 3$0^{\circ}C$, eight light intensity conditions, 1, 000, 2, 500, 5, 000, 20, 000, 30, 000, 40, 000, 50, 000 and 60, 000lux, six soil water contents, 30, 45, 55, 70, 80 and 90％ of the saturated soil, during growth stage. Shading treatment was three conditions, 0, 25 and 50％, during the daytime in field conditions. Photosynthesis had a highly significant relationship with temperature conditions in a quadratic regression model, from which the temperature for the plant growth was estimated to be 17.7$^{\circ}C$. A highly significant quadratic regression was noted between temperature and leaf width or root weight of V. fauriei. It was estimated from the regression equation that the optimum temperature for root growth was 20.3$^{\circ}C$. The content of essential oil and extract rate of root was the highest in the 15~2$0^{\circ}C$. Photosynthesis also was significantly affected by light intensity in a quadratic regression model, from which the optimum light intensity for the growth was estimated to be 40, 000lux. Root yield was more produced in Jinbu than that of in Umsung. The root yield was increased by the shading treatment in Umsung, whereas it was decreased by the shading treatment in Jinbu. The content of essential oil was not affected by the shading treatment of plants during the cultivation, while the compositions of components of essential oil were related to the growing locations. As soil water content was higher, the growth and content of root extract were increased. The optimum soil moisture for the growth of V. fauriei was 80~90％ of the saturated soil. In summary, the results indicated that the growth, yield and component of essential oil in V. fauriei were affected by environmental factors as well as soil moisture.

• The Korean Journal of Mycology
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• v.24 no.1 s.76
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• pp.38-48
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• 1996

The survival or colonization of beneficial organsisms and suppression of root rot of ginseng (Panax ginseng) by two distinct bacteria, Pseudomonas cepacia, Bacillus cereus and three mycorrhiza in pot soil were investigated and compared with uninoculated root. In separate inoculation, colonization of roots by P. cepacia was maintained at 6.25 (log cfu/g root) during growth for 10 days under pot culture conditions comparing to $5.62{\sim}6.19$ by mixed treatment with other organisms. Colonizations of P. cepacia were gradually decreased from 6.25 (log cfu/g root) in 10 days growth to 3.01 (log cfu/g root) in 270 days incubation period. This reduction was also investgated in combination treatments by B. cereus or F. solani. The numbers of Fusarium spp. were colonized high number in rhizosphere soil from 3.33 to 3.67 (log cfu/g root) in control within $10{\sim}60$days after treatment of pathogen F. solani, but it's numbers were markedly decreased in 270 days cultivation of plant from 3.33 to 1.02 (log cfu/g root) after treatment. In treatment of beneficial strains of P. cepacia and B. cereus, P. cepacia significantly suppressed the development of root rot from 4.3 in control to 1.2 in treatment, whereas B. cereus alone had no effect on the rate of disease suppression. The disease index $(1.8{\sim}2.3)$ in combination of two bacteria was reduced in plants inoculated with both P. cepacia and B. cereus comparing to the index (4.3) of control. As an effect of inoculation with mycorrhiza on disease suppression, suppression of root rot by F. solani was reduced to $1.2{\sim}1.6$ in disease index in treatment of Glomus albidum and Acaulospora longular comparing to 4.3 of control. In the treatment of bacterial strain P. cepacia and mycorrhizal fungus Glomus albidum, the disease suppression was apparent to 1.2 and 1.2 comparing to 4.3 of control in disease index respectively.

• Journal of Bio-Environment Control
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• v.23 no.4
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• pp.293-302
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• 2014

This study was carried out to develop rain shelter which can make an appropriate size and environment for Chinese cabbage rainproof cultivation. Fifty three farms with chinese cabbage rainproof cultivation system have been investigated to set up width and height of rain shelter. Mostly the width of 6m was desired for rain shelter and the height of 1.6m for their eaves, so these values were chosen as the dimensions for rain shelter. After an analysis of their structural safety and installation costs by the specifications of the rafter pipe, Ø$25.4{\times}1.5t$ and 90cm have been set as the size of rafter that such size costs the least. This size is stable with $27m{\cdot}s^{-1}$ of wind velocity and 17cm of snow depth. Therefore it is difficult to apply this dimension to area with higher climate load. In order to sort out such problem, the rain shelter has been designed to avoid damage on frame by opening plastic film to the ridge. Once greenhouse band is loosen by turning the manual switch at the both sides of rain shelter and open button of controller is pushed then switch motor rises up along the guide pipe and plastic film is opened to the ridge. Chinese cabbage can be damaged by insects if rain shelter is opened completely as revealed a field. To prevent this, farmers can install an insect-proof net. Further, the greenhouse can be damaged by typhoon while growing Chinese cabbage therefore the effect of an insect-proof net on structural safety has been analyzed. And then structural safety has been analyzed through using flow-structure interaction method at the wind condition of $40m{\cdot}s^{-1}$. And it assumed that wind applied perpendicular to side of the rain shelter which was covered by insect-proof net. The results indicated that plastic film was directly affected by wind therefore high pressure occurred on the surface. But wind load on insect-proof net was smaller than on plastic film and pressure distribution was also uniform. The results of structural analysis by applying pressure data extracted from flow analysis indicated that the maximum stress occurred at the end of pipe which is the ground part and the value has been 54.6MPa. The allowable stress of pipe in the standard of structural safety must be 215 MPa or more therefore structural safety of this rain shelter is satisfied.

• The Korean Journal of Mycology
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• v.23 no.3 s.74
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• pp.246-256
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• 1995

Phenotypic characteristics, pathogenicity and fungicides resistance of fifty one isolates of Botrytis cinerea obtained from various host plants were observed and determined. The relationships between these characteristics were also investigated on the basis of isolation host plants. The isolates of B. cinerea varied in the capacity of sclerotia formation and sporulation. The pathogenicity of 44 isolates from tomato, cucumber, and strawberry was significantly stronger with 3.2 cm in average diameter of necrotic lesions on cucumber leaves than that of seven isolates from other host plants such as orange, gerbera, ginseng, kiwi, grape, pear and from butter with 1.8 cm in average diameter of necrotic lesions. Benomyl resistance of 12 isolates from tomato plants was much higher with the $EC_{50}$, 562 ppm than that of 19 isolates from various host plants. Diethofencarb resistance, however, of 11 isolates from strawberry plants was highest with the $EC_{50}$, 210 ppm among isolates from other host plants. Polygalacturonase activity varied among isolates in the range of 0 to 103 unit and that of isolates from tomato, cucumber and strawberry was slightly lower than that of isolates from other host plants. No significant relationship between pathogenicity and fungicides resistance, polygalacturonase activity was found among 51 isolates of B. cinerea. Isozyme patterns of polygalacturonase produced from two strongly and weakly pathogenic isolates (FC122, KC6) were slightly different depending upon carbon sources during cultivation.

• Research in Plant Disease
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• v.17 no.3
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• pp.311-316
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• 2011

Pepper powdery mildew causes increasingly economical damage due to increased cultivation of pepper in greenhouses. To assess resistance of pepper resources against pepper powdery mildew, we developed a novel evaluation formula for pepper resistance against powdery mildew. The evaluation formula named S index is as follows; (number of the highest disease leaf/top leaf number)-(number of the lowest disease leaf/top leaf number). Positive correlation (81%, P = 0.01) between S index and authentic disease leaf rate was observed from the pepper plants infected by powdery mildew. Various pepper species from our genetic resources were evaluated to identify pepper varieties conferring resistance against powdery mild using S-index. Capsicum frutescens accessions 3CA131 and C. baccatum accessions 3CA0162, 3CA174, 3CA176 showed high resistance to powdery mildew, but none of C. annuum was resistant. Results suggest that S-index proposed in this study is useful to assess resistance evaluation of powdery mildew in chili pepper breeding.

• The Korean Journal of Food And Nutrition
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• v.25 no.3
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• pp.430-435
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• 2012

The objectives of this study were to form comparisons of total polyphenol compounds, the antioxidant activities and the urushiol contents of lacquer tree(Rhus verniciflua) bark and the sensory properties of chicken soup was made with lacquer tree bark that was cultivated from different cultivation areas; Hamyang, Wonju and China. Total polyphenol contents of Hamyang, Wonju and China were estimated as $375.28{\pm}3.48$, $403.60{\pm}6.6$ and $311.06{\pm}4.99$ mg/g. The total flavonoids contents of Hamyang, Wonju and China were measured as $374{\pm}14.12$, $683.70{\pm}12.64$ and $334.64{\pm}18.40$ mg/g. The total phenolic compounds and flavonoids concentration, DPPH radical scavenging activity, and ABTS radical scavenging of lacquer tree cultivated in Wonju were higher than the others; Hamyang and China. The urushiol content of lacquer tree bark from Hamyang was $4.59{\pm}0.04$ ppm and higher than others. Urushiol was not detected in China lacquer tree bark. Sensory evaluation tests for chicken soup containing lacquer tree bark showed that the scores of Wonju lacquer tree bark chicken soup was highest, however there are no differences between Hamyang, Wonju, and China significantly(p<0.05).

• Korean Journal of Weed Science
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• v.17 no.4
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• pp.390-399
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• 1997

This experiment was conducted to introduce PAT (phosphinothricin acetyltransferase, non-selective herbicide bialaphos resistant gene) gene into potato (Solanum tuberosum. cv. Desiree). Optimal shoot regeneration from leaf discs and stem segments was obtained in MS medium supplemented with 0.1 mg/L IBA and 0.5 mg/L BA, and the frequency of shoot regeneration was 54% in left discs and 46% in stem segments. In this condition, leaf discs and stem segments of potato were co-cultivated with A. tumefaciens MP90 which contained binary vector with GUS: :NPTII gene and PAT gene. Transgenic shoots were regenerated from leaf and stem-derived calli on selection medium with 100mg/L kanamycin. The 100${\mu}M$ acetosyringone treatment during the co-cultivation highly enhanced(4 times than the control) the shoot regeneration on selection medium. When the putative transgenic plants were transferred to medium with 10mg/L basta, all of them were survived. After PCR. GUS test, and Southern blot analysis of the survived plant, we confirmed that the gene was stably integrated into the potato genome and expressed. After the transgenic plants were transplanted in soil, and the transgenic plants were sprayed with the herbicide basta (300ml/10a), the transgenic plants remained green but control plants were died.

• Korean Journal of Soil Science and Fertilizer
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• v.40 no.6
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• pp.454-459
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• 2007

This experiment was conducted to investigate the effect of long-term continuous application of fertilizers for rice cultivation from 1954 to 2003. Changes of physical and chemical properties of paddy soil and the rice yield by continuous application of fertilizers, particularly rice straw compost, over fifty years were discussed in this paper. The rice yields of compost applied plots were 5~12% higher while those of no fertilizer plots were 21~38% lower compared to those of NPK fertilizers applied plots. Uptakes of T-N, $P_2O_5$, $K_2O$, CaO, MgO, and $SiO_2$ by rice plants were significantly increased by the application of straw compost. Bulk density, hardness, and liquid phase of soil in compost applied plots were significantly decreased while gaseous phase and cation exchange capacity (CEC) of soil were increased compare to those in NPK plots. When the bulk density of soil was increased the rice yield was decreased. The soil organic matter (SOM) content tended to increase in compost applied plots whereas no significant differences were found in other treatments. The soil organic matter content increased by $0.4g\;kg^{-1}\;yr^{-1}$ when $7.5Mg\;ha^{-1}\;yr^{-1}$ of rice straw compost applied in paddy land. The compost application rate recommendation for rice cultivation in Korea could be revised by the results of this study.

• Korean Journal of Environmental Agriculture
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• v.37 no.4
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• pp.251-259
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• 2018

BACKGROUND: Various culture media have been used for hydroponic cultures of horticultural plants under the smart greenhouses with natural and artificial light types. Management of the culture medium for the control of medium amounts and/or necessary components absorbed by plants during the cultivation period is performed with ICT (Information and Communication Technology) and/or IoT (Internet of Things) in a smart farm system. This study was conducted to develop the cloud-based data analysis system for effective management of culture medium applying to hydroponic culture and plant growth in smart greenhouses. METHODS AND RESULTS: Conventional inorganic Yamazaki and organic media derived from agricultural byproducts such as a immature fruit, leaf, or stem were used for hydroponic culture media. Component changes of the solutions according to the growth stage were monitored and plant growth was observed. Red and green lettuce seedlings (Lactuca sativa L.) which developed 2~3 true leaves were considered as plant materials. The seedlings were hydroponically grown in the smart greenhouse with fluorescent and light-emitting diodes (LEDs) lights of $150{\mu}mol/m^2/s$ light intensity for 35 days. Growth data of the seedlings were classified and stored to develop the relational database in the virtual machine which was generated from an open stack cloud system on the base of growth parameter. Relation of the plant growth and nutrient absorption pattern of 9 inorganic components inside the media during the cultivation period was investigated. The stored data associated with component changes and growth parameters were visualized on the web through the web framework and Node JS. CONCLUSION: Time-series changes of inorganic components in the culture media were observed. The increases of the unfolded leaves or fresh weight of the seedlings were mainly dependent on the macroelements such as a $NO_3-N$, and affected by the different inorganic and organic media. Though the data analysis system was developed, actual measurement data were offered by using the user smart device, and analysis and comparison of the data were visualized graphically in time series based on the cloud database. Agricultural management in data visualization and/or plant growth can be implemented by the data analysis system under whole agricultural sites regardless of various culture environmental changes.

• Korean Journal of Soil Science and Fertilizer
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• v.43 no.5
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• pp.616-623
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• 2010

Plant samples from 49 sites for Chinese cabbage, 28 sites for radish, 16 sites for cabbage, 8 sites for head lettuce, 20 sites for onion from farmers' and experimental fields in highland of Korea were collected and analyzed to find out the uptake patterns of nitrogen (N), phosphorus (P) and potassium (K) by altitude. Dry weight and uptake of N, P and K were increased at higher altitude in most vegetable crops. Nutrition uptake by Chinese cabbage was 163 ~ 283 kg $ha^{-1}$ for N, 42 ~ 69 kg $ha^{-1}$ for $P_2O_5$ and 146 ~ 270 kg $ha^{-1}$ for $K_2O$ according to altitude. Nutrient uptake by radish according to altitude was 153~159 kg $ha^{-1}$ for N, 38 ~ 46 kg $ha^{-1}$ for $P_2O_5$, and 151 ~ 185 kg $ha^{-1}$ for $K_2O$. In case of cabbage, the plant uptakes of N, P, and K were increased at altitudes of 600 ~ 1,000 m. Nutrient uptake of cabbage was 280 ~ 348 kg $ha^{-1}$ for N, 34 ~ 87 kg $ha^{-1}$ for $P_2O_5$, and 209 ~ 290 kg $ha^{-1}$ for $K_2O$ according to altitude. Uptakes of N-$P_2O_5-K_2O$ by head lettuce at an altitude of 800 ~ 850 m were 93-26-126 kg $ha^{-1}$, respectively. Uptakes of N-$P_2O_5-K_2O$ by onions at an altitude of 600 ~ 800 m were 313-140-234 kg $ha^{-1}$, respectively, but there was no tendency in nutrition uptake patterns by altitude. Small cultivation areas used for leaf vegetable crops do not have fertilizer recommendation standards in alpine regions. It might be preferable to use a correction factor equivalent to the index of available nutrient uptake for the determination of N, P and K fertilizer application rates.