• Korean Journal of Organic Agriculture
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• v.18 no.1
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• pp.93-104
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• 2010

This study was conducted screening of the population densities of fungal pathogens and insect and observed the disease symptoms on the organic sweet corn seed producing field from 2008 to 2009. The dissemination spores, Alternaria sp., Cladosporium sp., Helminthosporium sp., Pyricularia sp., Collectotrichum sp., and Bipolaris sp., were detected and the three fungal spores from the front were observed for whole growth stage. Seed and seedling diseases were shown as the rotted seed and damping-off seedling caused by Penicillium sp. and Rhizoctonia sp.. The larva of Black cutworm cut down the root crown of seedlings. The damaged plants were ranged from 14% to 16%. On the Oriental corn borer, the population densities and the percentage of damaged plants were showed a low difference between two sweet corn varieties. The population densities of Oriental corn borer were scored as from 3.5 to 20.5 in 2008 and from 0.5 to 6 in 2009. Also the percentage of damaged plants were significantly increased until harvesting stage and was recorded from 7.5% to 21% in 2008 and from 1% to 46% in 2009. On the Corn leaf blight, the percentage of diseased plant were scored from 7% to 34% in 2008. The first occurrence of date was after June 18, and the percentage of diseased plant was continuously increased after August 21 and the values of diseased plants was ranged from 56% to 69% in 2009. On common smut, the percentage of diseased plant was recorded from 5% to 15% in 2008, and the first occurrence date were delayed as 17 days (July 17) and were showed less than 8% of diseased plants in 2009. Corn Southern Leaf spot was scored as average 11% at early stage and showed high score as 62% at September 19 in 2008. In 2009, the first occurrence date were advanced about 20 days (after June 8), and continuously increased up to 86% in 2009.

• Korean Journal of Weed Science
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• v.31 no.3
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• pp.260-270
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• 2011

This study was carried out to examine the effect of rice bran, barley bran, burned rice bran, and burned barley bran on the growth and yield of Chinese chive (Allium tuberosum Rottler), taro (Colocasia esculenta), and weed control. When the above 4 brans were examined 13, 27, 41 and 57 days respectively after application, the plant height of Chinese chive applied with burned barley bran was significantly higher than non-treated control, whereas the other brans did not have any distinct effect on the plant height or population number of Chinese chive. However, when examined 57 days after the application of the above 4 brans, all the plants applied with brans showed more than twice the improvement in shoot fresh weight compared with non-treated control. A chemical analysis of soil 57 days after the application of the above 4 brans showed that the soils were richer in available phosphate and organic matter. Shoot fresh weight of Chinese chive at 2 weeks after cutting was significantly higher in barely bran treated plot than in non-treated plot. In the case of taro, only taro plots transplanted when 10 cm tall and applied with barley bran showed an improvement in growth increment of both the underground and above parts. However, when sowed seeds after the application of the 4 brans, the yield of taro was reduced by the brans. Thus this research indicates that the effect of brans is differ based on the amount of bran application as well as crops. The effect of weed control on Echinochloa crus-galli, Digitaria clliaris, Chenopodium album, and Solanum nigrum as affected by brans was very low in pot conditions. Weed efficacy of the brans was also very low in field conditions. Growth of Chinese cabbage and garland chrysanthemum was inhibited 63% and 37% by rice bran at $4,000kg\;ha^{-1}$, respectively, but other crops such as maize, squash, cucumber, and Chinese chive were inhibited by 0-20%. These results were similar to that of barley bran except for Chinese cabbage.

• The Korean Journal of Nuclear Medicine Technology
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• v.15 no.1
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• pp.121-125
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• 2011

Purpose: The DNA-type virus HBV, discovered by D. Dane and others in 1976, is approximately 42nm big and known as the main cause of liver-related diseases around the world. HBsAg has 4 kinds of subtypes including adw, adr, ayw and ayr and besides common antigen factor a, there are d, y, r, w. From the methods of serologically testing HBV, IRMA, EIA and CLIa were developed for testing HBsAg and are being used in examining the surface antigen of HBV. In this study, among the methods for testing HBV, the recently developed RIAKEY Ultrasensitive HBsAg IRMA kit's sensitivity level and performance in detection of mutant forms were measured and compared with CLIA. Materials and methods: Two certified reference materials, which are WHO 1st International Standard 1985(80/549) and WHO 2nd International Standard 2003(00/588. subtype adw2, genotypeA), were used in the examination and the sensitivity level was measured by diluting these materials from 0.08 IU/ml to 0.005 IU/ml. The materials for examining the detection of mutant forms included 9 kinds of subtype 'ad' and one kind of subtype 'ay' purchased from DSI company. Also, with the use of positive and negative samples, they was compared with CLIA. Result: Ultrasensitive HBsAg kit based on IRMA method showed the detection of up to 0.01 IU/ml not only for WHO 1st International Standard 1985(80/549) but also for WHO 2nd International Standard 2003(00/588. subtype adw2, genotypeA) and the sensitivity level was measured as 0.01 IU/ml by WHO standard. In testing the performance for detection of mutant forms, the 9 kinds of subtype 'ad' and one kind of subtype 'ay' mutant materials were detected, demonstrating the capacity of detecting various types of mutant forms. Conclusions: With the clinical importance of sensitivity level and performance in detection of mutant forms increasing in the field of HBsAg diagnosis, the examination of IRMA's effectiveness using RIA method in the aspects of the sensitivity level and performance in detection of mutant forms was carried out and its result is as follows. The sensitivity level was measured as 0.01 IU/ml by WHO standard and it was possible to measure various types of mutant forms with high sensitivity. Thus it is suggested that more speedy and accurate reports could be produced from a nuclear medicine laboratory for clinical practitioners requiring results of various situations.

• Journal of The Korean Society of Grassland and Forage Science
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• v.6 no.1
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• pp.31-37
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• 1986

In order to study the possibility of grassland improvement by spring sowing in the forest, microenvironmental conditions, emergence, percentage of grasses and weeds, root weight and dry matter yield of grasses were investigated. Two field sites (forest grassland and full-sunlight grassland) and two sowing times (March 20 and April 10) were assigned. The condition of the forest grassland was area of pine trees with 50% shading, and the experiment was performed at the Livestock Experiment Station in Suweon, 1984. The results obtained are summarized as follows: 1. For germination and early growth of grasses, full-sunlight grassland was more advantageous than forest grassland. Growth after that stage, on the other hand, forest grassland was more suitable. Especially, during dry and high temperature season, temperature of soil surface and underground in the forest grassland were decreased by $6-7^{\circ}C$ and $3-4^{\circ}C$ each other, compared with those of the full-sunlight grassland. Also soil moisture content was continuously higher in the forest grassland. 2. At March 20 sowing the emergence time in the full-sunlight grassland was shortened by 8 days, compared with that of the forest grassland. In case of sowing on April 10, however, there was no difference between two grassland sites. 3. Grasses grown in the forest was more prostrate and leaves from them decayed more, compared with those of the full-sunlight grassland. 4. The percentage of grasses in the forest grassland was 80 to 85 %, on the other hand, that of the full-sunlight grassland was only 15 to 20 %. And the percentage of grasses tended to be high in the plot of early sowing time. 5. Dry root weight and root length of grasses grown in the forest were inferior to those of the full-sunlight grassland (P<0.05), but there was no significant difference between two sowing times. 6. Dry matter yield of grasses was significantly higher (P<0.05) in the forest grassland than in the full-sunlight grassland, and yield was influenced by sowing time. Higher yield (4,011 kg/ha) was produced in the plot of the forest grassland with early spring sowing. 7. From above results, it is suggested that grassland improvement by spring sowing in the forest is possible, and it is desirable to sow in early spring.

• Journal of Life Science
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• v.19 no.1
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• pp.123-128
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• 2009

Production of highly valuable immunotherapeutic proteins such as monoclonal antibodies and vaccines using plant biotechnology and genetic engineering has been studied as a popular research field. Plant expression system for mass production of such useful recombinant therapeutic proteins has several advantages over other existing expression systems with economical and safety issues. Immunotherapy of multiple monoclonal antibodies, which can recognize multiple targeting including specific proteins and their glycans highly expressed on the surface of cancer cells, can be an efficient treatment compared to a single targeting immunotherapy using a single antibody. In this study, we have established plant production system to express two different targeting monoclonal antibodies in a single transgenic plant through crossing fertilization between two different transgenic plants expressing anti-colorectal cancer mAbCO17-1A and anti-breast cancer mAbBR55, respectively. The F1 seedlings were obtained cross fertilization between the two transgenic parental plants. The presence, transcription, and protein expression of heavy chain (HC) and light chain (LC) genes of both mAbs in the seedlings were investigated by PCR, RT-PCR, and immunoblot analyses, respectively. Among all the seedlings, some seedlings did not carry or transcribe the HC and LC genes of both mAbs. Thus, the seedlings with presence and transcription of HC and LC genes of both mAbs were selected, and the selected seedlings were confirmed to have relatively stronger density of HC and LC protein bands compared to the transgenic plant expressing only each mAb. These results indicate that the F1 seedling plant with carrying both mAb genes was established. Taken together, plant crossing fertilization can be applied to generate an efficient production system expressing multiple monoclonal antibodies for immunotherapy in a single plant.

• Applied Biological Chemistry
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• v.47 no.3
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• pp.344-350
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• 2004

This study was conducted to develop and assess the applicability of mixed-bed ion exchange resin capsules for water quality monitoring in small agricultural watershed. Recoveries of resin capsules for inorganic N and P ranged from 96 to 102%. The net activation energies and pseudo-thermodynamic parameters, such as ${\Delta}G^{o\ddag},\;{\Delta}H^{o\ddag},\;and\;{\Delta}S^{o\ddag}$ for ion adsorption by resin capsules, exhibited relatively low values, indicating the process might be governed by chemical reactions such as diffusion. However, those values increased with temperature coinciding with the theory. The reaction reached pseudo-equilibrium within 24 hours for $NH_4-N\;and\;NO_3-N$, and only 8 hours for $PO_4-P$, respectively. The selectivity of resin capsules were in the order of $NO_3\;^-\;>\;NH_4\;^+\;>\;PO_4\;^{3-}$, coinciding with that of encapsulated Amberlite IRN-150 resin. At the initial state of equilibrium, the resin adsorption quantity was linearly proportional to the mass of ions in the streams, but the rate of movement leveled off, following Langmuir-type sorption isotherm. The overall results demonstrated that the resin capsule system was suitable for water quality monitoring in small agricultural watershed, judging from the reaction mechanism(s) of the resin capsule and the significance of model in field calibration.

• Korean Journal of Agricultural and Forest Meteorology
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• v.2 no.1
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• pp.1-8
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• 2000

The objectives of this study were to investigate weather conditions which induced discolored grains and viviparous germination, and to evaluate yield responses following viviparous germination during mid- and late- ripening stage, the submergence during reproductive growth stage, and lodging in the yellow ripe stage. Weather conditions which caused glume discoloration at heading stage were 21.3-26.4$^{\circ}C$ in average temperature, 75.2-98.4% in relative humidity, 19.3 in transpiration coefficient and 10.8-13.8 m/sec. in wind speed. Yield reduction was 26-27% and 10~17%, respectively, when the glume discoloration rates were 63.2-65.7% and 38.3-45.2%, obviously due to the decrease in percent of fertile grain and ripening ratio. Weather conditions during continuous rain for 7 days were 96% in relative humidity, 18.9$^{\circ}C$ in average temperature, 21.9$^{\circ}C$ in maximum temperature, and 16.8$^{\circ}C$ in minimum temperature, causing the most viviparous germination in Juanbyeo(45.5%), followed by Jinbubyeo(14.5%), Bongkwangbyeo(14.2%), and Obongbyeo(12.6%). Lateral tillers started to occur when the submergence at the depth of 1.5-2 m lasted one day during the reproductive growth stage. The submergence for 2-3 days at 3-4 m of water depth induced 269-571 lateral tillers/m$^2$, supporting 32-52% of the total yield. The rice yield in the paddy fields which were left under the lodging conditions until harvesting was not different compared to that of the paddy fields which were kept upright by tieing them together after lodging, but perfect grain ratio decreased about 9.1% in the transplanting culture and 12.5% in the direct seeding culture on dry paddy field because of the increase in immature grains.

• Research in Plant Disease
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• v.11 no.2
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• pp.128-134
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• 2005

This study was conducted to elucidate effect of environmental factors on the development of white rot. In order to identify the causal agents causing white rot of Allium crops, we compared DNA profiles of a representative isolate, Sclerotium cepivorum, introduced from foreign country with Korean isolates using UP-PCR. As a result, Sclerotium isolates forming round-shaped sclerotia were identified as Sclerotium cepivorum pertaining in UP-PCR b group and Sclerotium isolates farming anamorphic-shaped sclerotia presumed to be a novel species of Sclerotium based on DNA profiles of UP-PCR. There was a big difference in DNA band pattern between two species of Sclerotium isolated in Korea. Electron micrographs of scanning electron microscope and transmission electron microscope showed morphological differences in sclerotial surface structure and rind layers between two species of Sclerotium. There were more wrinkles and pore spaces on sclerotial surface of Sclerotium sp. forming anamorphic-shaped sclerotia than that of Sclerotium cepivorum forming round-shaped sclerotia. Both of two white rot pathogens grew well at the temperature range of $10-25^{\circ}C$ with optimal temperature of $20^{\circ}C$. Sclerotia of the two pathogens were well formed at $20^{\circ}C$ and well germinated at the temperature range of $20-24^{\circ}C$, Effect of pre-incubation of sclerotia on destruction of sclerotial dormancy of two pathogens was evaluated through storing sclerotia under different temperature condition. The sclerotia of the two pathogens showed an increased capacity to germinate on potato dextroise agar when the sclerotia were incubated for 7 days at $10^{\circ}C$ after pre-treatment at $35^{\circ}C$ for 7 days. At that time, germination rate of Sclerotium sp. and 5. cepivorum was $100\%\;and\;70\%$, respectively. Flooding period and treatment temperature had an effect on sclerotial survival rate of the two pathogens. As flooding period and treatment temperature increased, sclerotial germination rate of the two pathogens decreased. It was confirmed that soil humidity played an important role on development of white rot. It was the highest disease incidence of garlic white rot when garlic were sown at potted soils infested with the two pathogens and adjusted soil humidity to $15\%$ (field moisture capacity, about -300 mb). As soil humidity increase or decrease based on $15\%$ of soil humidity, disease incidence decreased move and more.

• Research in Plant Disease
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• v.23 no.2
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• pp.150-158
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• 2017

Pear scab caused by Venturia nashicola has been reported as an important disease of pear resulting in lowering the quality of pear fruits. In this study, it was conducted to investigate the relationship between resistance of V. nashicola and mutation of ${\beta}$-tubulin gene and the fungicide resistance in field isolate group in benzimidazole fungicides. Responce of V. nashicola to carbendazim could be classified into 3 groups as sensitive that does not grow at all on PDA amended with $0.16{\mu}g/ml$ of carbendazim, low resistance that could not grow in $4.0{\mu}g/ml$ medium, and high resistance that can grow even at $100{\mu}g/ml$. Thirty isolates of V. nashicola collected from 3 regions as Wonju, Naju, and Okcheon were highly resistant to carbendazim. Analysis of the nucleotide sequence of ${\beta}$-tubulin gene of V. nashicola showed that there was no difference in the nucleotide sequence between the sensitive and the low-resistant isolate, but GAG at codon 198 (glutamic acid) was replaced with GCG (alanine) in the high-resistant isolate. Among 10 isolates obtained from the Okcheon, 5 isolates showed the substitution of glycine for glutamic acid, which were resistant to carbendazim, but more sensitive to the mixture of carbendazim and diethofencarb than others. Through these results, all isolates of V. nashicola isolated in pear orchard were found to be resistant to benzimidazoles. Also, mutants E198A and E198G at ${\beta}$-tubulin were found to be important mechanisms of V. nashicola resistance against benzimidazole fungicides.

• Journal of Soil and Groundwater Environment
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• v.8 no.2
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• pp.62-69
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• 2003

The aim of research is the evaluation of the $Cr^{6+}$ emission features of the liquid injection through emission experiments in varying conditions, based on a field-mixing ratio. The results showed that the content of $Cr^{6+}$ content in cement measured had an Ordinary Potland Cement (OPC) of 25.3 mg/kg, which constitute the largest portion among the other materials. Likewise, the emission experiment of homo-gel and sand-gel generally satisfied the standard of KSLT (Korea Standard Leaching Test) in waste of 1.5 mg/L, but in case of the standard of KSLT in soil the emission of OPC $Cr^{6+}$ of 4.85 mg/kg. These conditions is a little exceeded the criteria in the ‘Ga’ area in terms of Korea Soil Environmental Preservation Law. In addition, results generated by the mock-up injection facilities revealed that $Cr^{6+}$ emission increased as Water/Cement and injection pressure increased. At injection pressure higher than 4 kg/㎤, $Cr^{6+}$ emission exceeded the water preservation standard of 0.5 mg/L. Similarly, a pattern experiment of C $r^{6+}$ emission according to pH was conducted, in order to evaluate the $Cr^{6+}$ emission features of grout materials in leachate below pH 5 such as pH 4 acid rain or landfill. Results show that $Cr^{6+}$ emission dramatically increased in high acidic or basic state. It indicates that $Cr^{6+}$ emission will probably increase in an environment where grout materials are injected. On the other hand, concentration of leachate was determined in areas where grout materials are used. The results show that the concentration of emission in an ultra purity condition does not manifest intensity, and is affected in the OPC>MC>SC order. It means that the pollutants or $Cr^{6+}$ emission increases with decreasing concentration. As such, $Cr^{6+}$ emission will probably exceed the countermeasure criteria according to the types of gout materials. Similarly, high pressure or injection will cause increased $Cr^{6+}$ emission. Therefore, the selection of materials or mixing ratio should be considered in general as well as according to specific industries, based on the strength and pH of $Cr^{6+}$ emission.