• Journal of Ginseng Research
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• v.14 no.2
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• pp.291-296
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• 1990

Various rates of 2,4-D were sprayed on 2 and 3 year old ginseng plants as foliar spray to define the critical concentration. No apparent plant injury was noticable for those ginseng plants when application concentration of 2,4-D doubled the recommended dosage (70 ml/10a). Neither abnormal foliar change occurred nor any inhibition in leaf and stem growth was resulted for the plants treated with 2,4-D concentrated two times of the recommended dosage. When the rates of 2,4-D application were increased greater than this level, injury ratings increased linearly with the rates of 2,4-D application and plant you was inhibited. Ethylene gas was not produced from the ginseng plant treated with 2 times concentrated 2,4-D, however the ginseng plants produced 0.03 to 0.09 ppm ethylene gas when the rate of application were increased 3 and 4 times, respectively. On the other hand the soybean treated with the recommended amount of 21-D produced ethylene gas of 10-20 times higher compared with ginseng plants and died. Photosynthesis ability of the ginseng leaf was significantly decreased by 2,4-D foliar application but it was recovered 4 weeks after 2,4-D foliar treatment. The herbicide 2,4-D was applicated to 2,3 and 4 years old ginseng plants as foliar spray with the rates of 0.5, 1.0, 1.5 and 2.0 times of the recommended dosage to define the effects of 2,4-D on the plant growth and root yield of the ginseng. There were no significant differences in the leaf and stem growth between untreated and 2,4-D treated plant. Berry maturing of 3 and 4 year old ginseng was not influenced by 2,4-D. The root weight of 4 years old ginseng plant was not reduced by application of 2,4-D concenrated 2 times of the recommended dosage, Application time of the herbicide 2,4-D had no effects on the leaf or stem growth of 2,3 and 4 year old year old ginseng plants. When the ginseng seedling was treated with 2,4-D, detrimental phenomena as stem bending and docoration of seedling leaf margin occurred, but stem bending was recovered in a few day s. Keywords Panax ginseng C.A. Meyer, 2,4-D , herbicide.

• Journal of the Korean institute of surface engineering
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• v.43 no.4
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• pp.176-179
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• 2010

The InAs thin films were grown on GaAs(100) substrate with $2^{\circ}C$ tilted toward [$0\bar{1}\bar{1}$] with different As beam equivalent pressure (BEP) by using molecular beam epitaxy. Growth temperature and thickness of the InAs thin films were $480^{\circ}C$ and 0.5 ${\mu}m$, respectively. We studied the relation between the As BEP and the properties of InAs thin films. The properties of InAs thin films were observed by reflection high-energy electron diffraction (RHEED), optical microscope, and Hall effect. The growth, monitored by RHEED, was produced through an initial 2D (2-dimensional) nucleation mode which was followed by a period of 3D (3-dimensional) island growth mode. Then, the 2D growth recovered after a few minutes and the streak RHEED pattern remained clear till the end of growth. The crystal quality of InAs thin films is dependent strongly on the As BEP. When the As BEP is $3.6{\times}10^{-6}$ Torr, the InAs thin film has a high electron mobility of 10,952 $cm^2/Vs$ at room temperature.

• Horticultural Science & Technology
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• v.28 no.6
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• pp.973-979
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• 2010

The objective of this study was to determine the effect of electrical conductivity (EC) of nutrient solution on the growth, nutrient uptake of potted kalanchoe plants ($Kalanchoe$ $blossfeldiana$ 'New Alter') and the nutrient accumulation at the growing media with growth stage in ebb and flow subirrigation systems. Significant differences in leaf area, plant height, and dry weight of the plants were found among the different ECs of nutrient solution of 0.8, 1.6, 2.4, and $3.2dS{\cdot}m^{-1}$. Particularly the difference in plant growth became significantly greater from 5 weeks after treatment. The overall growth was the highest at EC $1.6dS{\cdot}m^{-1}$. Leaf area, plant height, and dry weight were maintained higher when EC increased to $2.4dS{\cdot}m^{-1}$, but rapidly decreased after EC $3.2dS{\cdot}m^{-1}$. The uptake of NO3-N was the greatest while that of $Mg^{2+}$ was the lowest at EC $1.6dS{\cdot}m^{-1}$, even though small differences were found among macro elements. The EC at the top layer of the growing media was 1 to 3 times higher than that at the bottom layer. Nutrient accumulation was accelerated in both the top and bottom layers with growth stage. At EC $3.2dS{\cdot}m^{-1}$, the growth of the plants was suppressed due to higher nutrient accumulation at the growing media. From the results, the strength and composition of nutrient solution should be determined by considering nutrient accumulation at the growing media in addition to EC of nutrient solution in ebb and flow subirrigation systems.

• The Korean Journal of Pesticide Science
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• v.13 no.4
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• pp.275-282
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• 2009

The effect of two plant growth-promoting rhizobacteria (PGPR) on plant growth and systemic protection against soft rot disease and stem rot disease of canola (Brassica napus), caused by Erwinia carotovora and Sclerotinia sclerotiorum was investigated in a laboratory and a greenhouse. Selected PGPR strains C4 and D8 were treated to canola seeds by soaking. Strains C4 and D8 significantly not only increased plant height and root length about 74% and 40.3% and also reduced disease severity of soft rot disease by 80% by C4 and D8 respectively, compared to the control. Especially strain C4 showed antifungal activity against 6 fungal pathogens, S. sclerotiorum, Rhizoctonia solani, Botrytis cinerea, Fusarium oxysporum, Phytophthora capsici and Colletotrichum acutatum. In greenhouse experiment, the seed treatment of both of them increased plant height, leaf width and leaf length of canola plant to 19.5% and 24.9%, 11.3% and 15.3%, and 14.1% and 20.7% by C4 and D8, respectively, and reduced disease severity of S. sclerotiorium. These results indicate that these two PGPR strains can decrease disease severity and increased plant growth under greenhouse condition. Therefore, these two bacteria have a potential in controlling Sclerotinia stem rot of canola. These strains have to investigate under field condition to determine their role of antibiosis, induced systemic resistance and plant growth promotion on canola.

• Korean Journal of Environment and Ecology
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• v.20 no.4
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• pp.425-435
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• 2006

The objectives of this research were to investigate the drought resistance as well as the growth of Wisteria floribunda seedlings with the soil water conditions. The seedlings for the research were grown in pots with strict water content control on a frame located outdoors. During the experiments, the soil water contents were adjusted to 5, 10, 20, 30, 40, 50, 60, and 70%. In addition, the effects of Rhizobium inoculation on the growth of seedlings were investigated. The experimental results are summarized as follows: 1. The seedlings in the pots with 5% soil water content withered to death due to the water stress. Withering or any distinct growth was not observed from the seedlings in the 10% soil water content. It can be inferred from these results that about 5% of soil water content is the wilting point of W. floribunda seedlings and about 10% is the critical soil water content of its growth in this experiment soils. Therefore, it seems that W. floribunda possesses a good drought resistance. 2. From the analyses of the main growth parameters such as stem elongation, diameter growth, leaf area growth and total dry weight, it was found that the seedling growth can be improved with increasing soil water contents. The relation between each growth parameter(Y) and the soil water contents(W) was well described by a quadratic equation, $Y=a+bW+cW^2$. 3. In soil water contents higher than 20%, the seedling growth(Y) was remarkable along with-its extended growing period, and related to the growing period(D) by a quadratic equation, $Y=a+bD+cD^2$. 4. The artificial inoculation of Rhizobiun promoted the growth of Wisteria floribunda seedlings. 5. Rhizobium was found to be more readily inoculated and to form more root nodules compared to seedlings grown in higher soil water contents.

• Korean Journal of Soil Science and Fertilizer
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• v.29 no.4
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• pp.360-364
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• 1996

Study on germination ratio and growth of lettuce affected by accumulated salt in vinyl house cultivation soils was investigated by pot test with EC 1.65. 3.50, 5.75. 7.15. 9.50 and 13.57 dS/m. (Germination rate of lettuce in different electric conductivity of 0, 2, 4, 6, 8 and 10 dS/m controlled with KCl were 96.7, 96.7, 87.8, 82.2, 52.2, and 27.8 % respectively. Standing ratio of lettuce in soil below 6 dS/m was more than 60% and in soils of 7.15, 9.50 and 13.57 dS/m they were 45, 32 and 31%, respectively. Growth and fresh weight of lettuces increased significantly in a low EC content soil. The fresh weight of lettuces in the soil of EC 3.50 dS/m was higher than that of the soil EC 1.65 dS/m by 22%, while another soils(EC: 5.75, 7.15, 9.50 and 13.57 dS/m) were decreased 3, 15, 60 and 62%, respectively. Relationship between soil EC and standing ratio of lettuce showed high correlation coefficient($r=-0.9057^{**}$). Therefore, in the field of vinyl houses concentrated salt, standing ratio of lettuce can be foreseen by soil EC [Y = -4.313x+ 82.95 (Y:standing ratio, x:soil EC)], also standing ratio and fresh weight of lettuce showed high correlation coefficient($r=0.8396^{**}$).

• Proceedings of the Korea Association of Crystal Growth Conference
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• 1996.06a
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• pp.537-537
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• 1996

• Korean Journal of Remote Sensing
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• v.16 no.2
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• pp.109-116
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• 2000

This study was carried out to assess the use of RADARSAT data which is C-band with HH polarization for the rice growth monitoring in Korea. Nine time-series data were taken by shallow incidence angle (standard beam mode 5 or 6) during rice growing season. And then, backscattering coefficients ($\sigma$$^{\circ}$) were extracted by calibration process for comparing with rice growth parameters such as plant height, leaf area index(LAI), and fresh and dry biomass. Field experimental data concerned with rice growth were collected 8 times for the ground truth at the study area, Tangjin, Chungnam, Korea. At the beginning of rice growth, backscattering coefficients were ranged from -l6~-l3dB when rice fields were not covered with rice canopy and flooded. At the maximum vegetative stage of rice, backscattering coefficients of the rice field were the highest ranging from -4.4dB~-3.1dB. The temporal variation of backscattering coefficient($\sigma$$^{\circ}$) in rice field was significant in this study. Backscattering coefficient ($\sigma$$^{\circ}$) of rice field was a little bit lower again after heading stage than before. This results show RADARSAT data is promising for rice monitoring.

• Plant Resources
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• v.3 no.2
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• pp.135-137
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• 2000

Callus cultures from leaf explants of Gypsophila paniculata L. cv. 'Bristol Fairy' have been tested their growth and morphogenic capacity on Murashige and Skoog medium supplemented with 0.l, 0.5, 1 and 3 mg/L 2,4-D. The frequency of callus formation ranged from 43.3% to 100%. The optimal 2,4-D concentration for promoting callus formation and growth was 0.5 to 3 ㎎/L. 4.2∼ 5.6% of adventitious roots were obtained with the use of 0.1 and 0.5 mg/L 2,4-D. Calli grown well on 1.0 mg/L 2,4-D was the heaviest among the calli grown in various concentrations.

• Asian-Australasian Journal of Animal Sciences
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• v.27 no.8
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• pp.1150-1156
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• 2014

This trail was conducted to study the effect of L-proline on the growth performance, and blood parameter in the weaned lipopolysaccharide (LPS)-challenged pigs. Thirty six pigs ($9.13{\pm}0.85$ kg) were assigned randomly to dietary treatments in a $2{\times}3$ factorial arrangement in a 20-d growth assay. Factors were intraperitoneal injection with saline or LPS, and three dietary L-proline supplement levels (0%, 0.5%, or 1.0%). On d 10, blood samples were collected at 3 h after LPS (100 ${\mu}g$ LPS/kg body weight [BW]) or saline injection. On d 20 of the trial, all pigs were orally administrated D-xylose (0.1 g/kg BW) at 2 h, and blood samples were collected at 3 h after LPS or saline injection. As a result, dietary supplementation with 0.5% proline had a tendency to increase average daily gain (ADG) in piglets during d 10 to 20 (p = 0.088). Without LPS challenge, dietary supplementation with 1.0% proline had no effect on growth hormone (GH) concentrations on d 10 (p>0.05), but decreased it after LPS challenge (p<0.05). There was LPS challenge${\times}$proline interaction for GH concentrations on d 10 (p<0.05). Dietary supplementation with 1.0% proline decreased glucagon concentration on d 10 after LPS challenge (p<0.05). In addition, dietary supplementation with proline increased superoxide dismutase (SOD) activity significantly on d 10 and 20 (p<0.05), and 1.0% proline increased heat shock proteins-70 concentration on d 10 (p<0.05). Moreover, proline supplementation increased diamine oxidase (DAO) concentrations after LPS challenge (p<0.05). There was LPS challenge${\times}$proline interaction for DAO (p<0.05). Furthermore, dietary supplementation with 1.0% proline increased the D-xylose level when no LPS challenge (p<0.05). These results indicate that proline supplementation could improve growth performance, increase SOD activities, and has a positive effect on the gastrointestinal tract digestibility in early weaned pigs.