• Journal of Ginseng Research
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• v.34 no.4
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• pp.274-281
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• 2010

This experiment was conducted to examine ginseng lines resistant and susceptible to high-temperature injury and to investigate characteristics of the selected lines: leaf burning phenomenon, chlorophyll content, quantum yield, and maximum light interception rate. The leaf burning phenomenon incidence rates of the resistant lines Yunpoong, high-temperature injury resistance (HTIR)1, HTIR2, and HTIR3 were low: 5.8%, 3.6%, 4.0%, and 1.9%, respectively. Resistance of the susceptible lines Chunpoong, high-temperature injury susceptible (HTIS)1, and HTIS2 was high: 58.5%, 23.2%, and 21.7%, respectively. The chlorophyll content (SPAD value) of the resistant lines Yunpoong, HTIR1, HTIR2, and HTIR3, which were exposed to high temperatures and intense light, remained as high at 24.8, 27.9, 24.9, and 30.6, respectively, but that of the susceptible lines Chunpoong, HTIS1, and HTIS2 was low at 21.0, 21.1, and 20.1, respectively. During the summer season, the quantum yield of the resistant lines (Yunpoong, HTIR1, HTIR2, and HTIR3) changed little, but that of the susceptible lines (Chunpoong, HTIS1, and HTIS2) changed dramatically. The maximum light interception rate (Fm/Fv value) for the resistant lines (Yunpoong, HTIR1, HTIR2, and HTIR3) was as high as 0.848, 0.794, 0.805, and 0.813, respectively, while that of the susceptible lines (Chunpoong, HTIS1, and HTIS2) was 0.678, 0.642, and 0.717, respectively. Based on these results, the high-temperature injury-resistant lines seemed to be less susceptible to high light, even at high temperatures. Future studies on red ginseng quality and its active ingredients in resistant ginseng lines and field experimentation will be conducted to verify the potential of the resistant lines.

• Korean Journal of Medicinal Crop Science
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• v.27 no.4
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• pp.278-283
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• 2019

Background: High temperature damage in ginseng is influenced by shading materials related not only to temperature, but also to light intensity and light quality. To address, this green-colored khaki shading sheet is widely used. As they are recently, developed, there is limited research information about their attributes and use. Methods and Results: The four-layered shading net (FLSN), blue-colored shading sheet (BCSS), aluminum-coated shading board (ACSB), and green-colored shading sheet (GCSS) were installed in the wooden A type of sun-block facilities. Two layered black, shading net was additionally used to cover the facilities since the beginning of June. The average temperature at the facility where different shades were tested was in the order of BCSS ($28.9^{\circ}C$) > FLSN ($27.7^{\circ}C$) > GCSS ($27.6^{\circ}C$) > ACSB ($27.1^{\circ}C$). However, high temperature injury rates were in order: FLSN > ACSB > GCSS > BCSS. Root weight vaired and was in the order: ACSB > GCSS > BCSS > FLSN. Conclusions: High temperature damage is possible not only because of temperature increase, but also due to various environmental light factors. Ginseng high temperature injury was minimal when BCSS or GCSS were used by difference of light quality. Although the root weight was higher in ACSB, it could be vulnerable to high temperature damage. Therefore, we propose using GCSS for ginseng shading.

• Korean Journal of Soil Science and Fertilizer
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• v.14 no.4
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• pp.201-209
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• 1982

In 1980, the abnormal low temperature was lasted during the late stage of rice growing season, thus low temperature injury occurred severely. The severity of the injury and nutrition absorption were investigated. The result obtained were summarized as follows: 1. It was considered that the severe low temperature injury of rice was caused by the low temperature and shorts of sunshine in the late growing season of rice, especially, the minimum air temperature which was lasted for a few days below critical reproductive growing temperature in the meiosis stage affected high the injury. 2. The low tmperature injury was lightened in the no nitrogen applied plot, and becoming severe with high nitrogen levels, but the balanced application of NPK lessened the low temperature injury. 3. The low temperature injury was more severe in Indica and Japonica hybrid than in Japonica cultivar, and the injury was shown as sterilizing, degraded spiklets, ill emerging of head and inhibition of nutrition absorption, etc. 4. Under the low temperature condition, $SiO_2$ content of rice plant was significantly reduced according to the increase of nitrogen levels. 5. Under the low temperature condition, the optimum application amount of nitrogen for Milyang 23, was 13, 6 kg/10a, this was approximately 10kg/10a smaller than average in usual year. The highly reduced rice yield was resulted from the cool injury, and the reducing rate of yield was larger in Indica and Japonica hybrid cultivar than in Japonica cultivar.

• Proceedings of the Korea Institute of Applied Superconductivity and Cryogenics Conference
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• 2003.10a
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• pp.243-245
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• 2003

The method to fabricate the cryostat of superconducting cable is extrusion type which is used Aluminum ingot under high temperature such as 45$0^{\circ}C$ and the cryostat is formed above cable core and MLI layer. In this case, it is expected to occur thermal injury in cable core and MLI layer, so it is necessary to study to prevent thermal injury. So in this paper, using simulation on radiation and convection which are accompany with fabricating cryostat, it is suggested to reduce the thermal injury. By measuring simulation temperature and real temperature, it is possible to check the temperature on cable core and MLI layer and using these temperature, it is possible to predict whether thermal injury is occurred or not on cable core and MLI layer.

• Korean Journal of Agricultural Science
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• v.27 no.2
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• pp.86-94
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• 2000

This study was carried out to determine the effectiveness of uniconazole in ameliorating low and high temperature injury in tomato plants(Lycopersicon esculentum Mill. cvs. Fireball and Patio). Plants were given a soil drench of 0, 0.001, 0.01 or $0.1mg{\cdot}pot^{-1}$ uniconazole, and after 14 days, were treated with 12-h day/12-h night cycles at $25/25^{\circ}C$, $2.5/25^{\circ}C$, $25/2.5^{\circ}C$ or $40/40^{\circ}C$ for 4 days in controlled-environment chamber. Number of damaged leaves per plant, reduction of stem elongation, and overall injury were high at $2.5/25^{\circ}C$, but more reduction of leaf elongation, delay of flowering, and abortion of floral bud were observed in plants at $40/40^{\circ}C$. There was difference in degree of injury between cultivars, thus, 'Fireball' was much affected by unfavorable temperature regimes. All concentrations of uniconazole reduced leaf and stem elongation, increased total chlorophyll concentration, delayed flowering, and significantly provided protection against low and high temperature injury in two cultivars. In general, the application of uniconazole did not inhibit flowering delay and floral bud abortion induced by high and low temperature exposure. Our results support the hypothesis that the role of uniconazole is related to defense system against oxidative stress induced by low temperature stress. Further research is required to clarifu the phytoprotective mechanism of this compound agaist high temperature stress.

• Journal of Ginseng Research
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• v.35 no.4
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• pp.449-456
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• 2011

Plant leaf cuticle is related to the prevention of moisture loss, transpiration, and diffusion of light reflection. The purpose of this study was to examine the morphological characteristics of ginseng leaves in ginseng plants resistant and susceptible to hightemperature injury (HTI) to be related with the leaf-burning. For the HTI resistant lines Yunpoong, high-temperature injury resistance (HTIR) 1, HTIR 2, and HTIR 3, and the HTI-susceptible line Chunpoong, the cuticle densities were 53.0%, 46.2%, 44.9%, 48.0%, and 17.0%; the adaxial leaf cuticle layers were 141.3, 119.7, 119.7, 159.4, and 85.0 nm in thickness; the abaxial leaf cuticle layers were 153.6, 165.8, 157.9, 199.6, and 119.4 nm in thickness; and the stomtal lengths were 21.7, 32.4, 29.4, 30.9, and $21.8{\mu}m$, respectively. All of these aspects suggest that HTI resistant lines have higher cuticle density, thickicker adaxial and abaxial leaf cuticle layers, and longer of stomta length than the HTI-susceptible line, protecting leaves from moisture loss and excessive transpiration under high temperatures to be resistant against the leaf-burning.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.20 no.1
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• pp.77-96
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• 2017

This study was carried out to clarify the climatic factors of the freezing injury for the judgement on the adaptation areas of evergreen broad-leaved trees. We surveyed and analyzed the climatic factors of the freezing injury to Machilus thunbergii Siebold & Zucc. on the streets with the analyzation of planting grounds, soil conditions and the surrounding buildings. This study showed that only the minimum air temperature factor out of the other climate elements, which were the annual precipitation; the average annual temperature; the average monthly temperature of january; the average monthly minimum temperature of January; the average temperature of the coldest month; the warmth index and the coldness index, was matched up with the previous theories and reports on the freezing damages on the evergreen broad leaved trees and Machilus thunbergii Siebold & Zucc. The freezing injury of Machilus thunbergii Siebold & Zucc was occurred when the mean minimum temperature of the coldest month(TMC) in winter season fell down below $-4.1^{\circ}C$ and the temperature fell down below $-9.2^{\circ}C$. The freezing damage on Machilus thunbergii Siebold & Zucc surrounded by high buildings were less than those surrounded by low buildings or at non buildings.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.13
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• pp.93-105
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• 1973

Differential tolerance of rice varieties, Tongil and Mangyung(or Milsung) varieties, against herbicides combined with Simetryne was investigated by the rate of application in 4 places; Jeonju, Gwangju, Iri and Milyang, whose soil textures were Lic, Sic, CL and Lic respectively. The results are summarized as follows: 1) Jeonju a. Initial crop injury At the rate of 2kg/10a prod. no initial crop injury was caused(both to Mangyung and Tongil varieties) on light clay soil, even when treated at high temperature of $30^{\circ}C$ and above. Crop injury was first caused at 3kg/l0a prod. to Tongil variety and the damage increased in proportion to the increase of application rate, while no crop injury was caused to Mangyung variety even at high rate of 5kg/l0a prod. b. Yield Tongil variety: Under high temperature condition in a vinyl house no statistical difference was observed between treated and hand weeding plot at the rates of 3kg/l0a prod. and below. Under air temperature conditions no statistical difference was observed between treated and hand weeding plot at the rates of 4kg/l0a prod. and below. Mangyung variety: No statistical difference was observed between treated and hand weeding plot at the rates of 5kg/l0a prod. and below both under air and high temperature conditions. 2) Gwangju a. Initial crop injury Although almost the same tendency as in Jeonju was observed, a little lighter crop injury was observed in general in Gwangju than in Jeonju at the time of application. And so, no crop injury was caused to Tongil variety until 4kg/l0a prod. and above. b. Yield Tongil variety: No statistical difference was observed between treated and hand weeding plot at 4kg/l0a prod. and below. Mangyung variety: No statistical difference was observed between treated and hand weeding plot at 4kg/l0a prod. and below. 3) Iri No crop injury was caused both to Tongil and Mangyung varieties at 4kg/l0a prod. and below. Also, no reduction of grain yield was observed. 4) Milyang A little lighter crop injury was observed in general. No crop injury was caused to Milsung variety at 5kg/l0a prod. ; Only a slight crop injury was caused to Tongil variety. Yield: No statistical difference was observed between treated and hand weeding plot both of Tongil and Milsung varieties even at 5kg/l0a prod. and below.

• Proceedings of The Korean Society of Agricultural and Forest Meteorology Conference
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• 2014.10a
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• pp.182-186
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• 2014

• Korean Journal of Agricultural and Forest Meteorology
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• v.11 no.4
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• pp.127-134
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• 2009

This study was carried out to investigate the effects of air temperature during midsummer on sunburn occurrence that had some problems recently on 'Fuji'/M.9 planting system in Korea. There was a positive relationship between sunburn incidence and accumulated days with high air temperature over $31^{\circ}C$, or accumulated total quantum per day. 'Fuji'/M.9 apple trees with relatively open canopies, compared to 'Fuji'/M.26, were more susceptible to sunburn injury because the fruit was more exposed to sunlight. In 'Fuji'/M.9 apple trees, those that were poor in vigor or with short bourse shoot length were more susceptible to sunburn injury. Sunburn incidence was affected by neither regions nor row orientations. Sunburn was observed most often on the fruits on the south and west sides of the trees. The reason was due to high skin temperature of the fruits reaching $40{\sim}45^{\circ}C$ under full sunlight.