• 한국작물학회지
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• 제44권2호
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• pp.129-133
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• 1999

Excessive soil water at vegetative growth stages during the rainy season induces yield losses in soybeans. Our objectives were to obtain basic information about the cultivar differences and to understand the stress-tolerance process for due to excessive soil water. Previous experiments revealed soybean genotypic differences in tolerance to excessive soil water. A field experiment was conducted at the Research Farm of Korea University near Seoul on 21 May 1998. Soybean[Glycine max (L.) Merrill] cultivars, 'Hannamkong' (sensitive) and 'Taekwan-gkong'(tolerant) were planted in vinyl-lined plots(1.2 x 4.2 x 0.3 m deep) and control plots. Drip irrigation began at VI growth stage to submerge the soil surface. Three weeks of excessive soil water treatment reduced all growth parameters measured to soybean plants. Excessive soil water stress resulted in decreases of N, P, K, Ca, Mg and Cu, and increases of Fe and Mn contents in soybean leaves. The stress index of tolerant cultivars under excessive soil water showed no large difference in soybean growth characteristics measured at three growth stages. However, K, Ca, Mg, Fe and Mn contents in soybean leaves appeared to differ between sensitive and tolerant cultivars. From the above results, stress and tolerance indices are proposed for a method to test cultivar differences in plant responses within a species under adverse growth environments.

• Nuclear Engineering and Technology
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• 제54권7호
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• pp.2475-2490
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• 2022

The Accident Tolerant Fuel (ATF) is a new concept of fuel, which can not only withstand the consequences of the accident for a longer time, but also maintain or improve the performance under operating conditions. ISAA is a self-developed severe accident analysis code, which uses modular structures to simulate the development processes of severe accidents in nuclear plants. The basic version of ISAA is developed based on UO₂-Zr fuel. To study the potential safety gain of ATF cladding, an improved version of ISAA, referred to as ISAA-ATF, is introduced to analyze the station blackout accident of PWR using ATF cladding. The results show that ATF cladding enable the core to maintain a longer time compared to zirconium alloy cladding, thereby enhancing the accident mitigation capability. Meanwhile, the generation of hydrogen is significantly reduced and delayed, which proves that ATF can improve the safety characteristics of the nuclear reactor.

• 대한지리학회지
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• 제36권3호
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• pp.247-257
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• 2001

한반도에 자생하는 상록활엽수의 종류에 따는 지리적 분포와 기후요소와의 관계를 분석하였다. 우리나라 의 61속 132종 상록활엽수 분포하는 지역의 수 수직적 고도 범위, 위도에 따라 7개의 그룹으로 분류되었다. 7개의 그룹은 다시 분포의 남한한계선을 갖는 한대성 상록활엽수와 북방한계선을 갖는 난대성 상롭활엽수로 나뉘었다. 한대성 상록활엽수와 난대성 상롭활엽수의 분포와 관련되는 기후요소늘 연평균기온(Ty). 1월 평균기온(T1). 1월 평균최저기온(Tmin1) 8월 평균기온(T8), 8월 평균최고기온(Tmax 8), 연교차(Tar) 등이며. 종류에 따라 분포에 영향을 미치는 기후요소는 달랐다. 난태성 상록활엽수의 분포에 중요한 것은 주로 1월 평균기온 -4$^{\circ}C$, 1월 평균최저기온 -9$^{\circ}C$이다. 한대성 상롭활엽수의 분포는 8월 평균기온 19$^{\circ}C$, 8월 평균최고기온 26$^{\circ}C$가 다른 기온조건보다 중요한것으로 판단된다..

• The Korean Journal of Ecology
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• 제21권3호
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• pp.313-320
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• 1998

Ameliorating effects of dolomite and sludge on the polluted soil sampled from Ulsan and yeocheon Industrial Complexes were investigated. Ameliorating effects were analysed by changes of soil properties and plant growth after treatment of dolomite and sludge. Soil properties were investigated by analysing organic matter, N, P, K, Ca and Mg contents and pH. Growth of sample plants was investigated by leaf area calculated from length and breadth of leaves and by biomass from diameter and height of sample plants. Quercus serrata and Celtis sinensis selected as tolerant plants in field survey were used as experimental plants. Treatment with dolomite showed ameliorating effects by increassing n, Ca, and Mg com\ntents, and pH of soil and by decreasing Al content. Treatment of sludge showed similar effects by increasing N, Ca, Mg and organic matter contents, and by decreasing A1 content. But treatment of sludge did not show any effect on pH. Both soil ameliorators showed accelerating effects on the growth of experimental plants in Ulsan soil. But those effects in Yeocheon soil were somewhat different. Treatment of sludge showed accelerating effects of the growth of both sample plants but dolomitic liming did not so. From those results, we confirmed availability of sludge, a kind of industrial waste, as one of ameliorators of the polluted soil. In addition, we recognized that soil properties had to be considered to select soil ameliorators suitable for restoration of degraded ecosystems.

• Journal of Plant Biotechnology
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• 제43권3호
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• pp.302-310
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• 2016

A study aimed at identifying putative drought responsive genes that confer tolerance to water stress deficit in tea plants was conducted in a 'rain-out shelter' using potted plants. Eighteen months old drought tolerant and susceptible tea cultivars were each separately exposed to water stress or control conditions of 18 or 34% soil moisture content, respectively, for three months. After the treatment period, leaves were harvested from each treatment for isolation of RNA and cDNA synthesis. The cDNA libraries were sequenced on Roche 454 high-throughput pyrosequencing platform to produce 232,853 reads. After quality control, the reads were assembled into 460 long transcripts (contigs). The annotated contigs showed similarity with proteins in the Arabidopsis thaliana proteome. Heat shock proteins (HSP70), superoxide dismutase (SOD), catalase (cat), peroxidase (PoX), calmodulinelike protein (Cam7) and galactinol synthase (Gols4) droughtrelated genes were shown to be regulated differently in tea plants exposed to water stress. HSP70 and SOD were highly expressed in the drought tolerant cultivar relative to the susceptible cultivar under drought conditions. The genes and pathways identified suggest efficient regulation leading to active adaptation as a basal defense response against water stress deficit by tea. The knowledge generated can be further utilized to better understand molecular mechanisms underlying stress tolerance in tea.

• BMB Reports
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• 제41권5호
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• pp.382-387
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• 2008

It is known that the stable protein 1 (SP1) detected in aspen plants remains soluble upon boiling and that sp1 expression in transgenic aspen is resistant to salt stress. Presently, we analyzed the effect of expression of SP1 in Arabidopsis thaliana plants and their response to high temperature stress. After $45^{\circ}C$ for 16 h, relative to wild type plants, sp1 transgenic plants exhibited stronger growth and were better in several physiological properties including chlorophyII, chlorophyII fluorescence, water content, proline content, and malondialdehyde content. These preliminarily results suggest that the over-expression of SP1 may notably enhance heat-tolerant level of transgenic A. thaliana plants.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2023년도 춘계학술대회
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• pp.156-156
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• 2023

Salinity is a major abiotic stress that limits rice productivity in many regions of the world. In order to develop salt stress tolerant rice plants, genetic engineering is a promising approach. We characterized the molecular function of rice C3H2C3 as a really interesting new gene (RING). Oryza sativa RING finger protein H2-3 (OsRFPH2-3) was highly expressed in 100 mM NaCl. To identify the localization of OsRFPH2-3, we fused vectors that include C-terminal GFP protein (35S;;OsRFPH2-3-GFP). OsRFPH2-3 was expressed in the nucleus in rice protoplasts. An in vitro ubiquitin assay demonstrated that OsRFPH2-3 possessed E3-ubiquitin ligase activity. However, the mutated OsRFPH2-3 were not possessed any E3-ubiquitin ligase activity. Under salinity conditions, OsRFPH2-3-overexpressing plants exhibited higher chlorophyll, proline, SOD, POD, CAT, and soluble sugar contents and lower H₂O₂ accumulation than wild-type plants, supporting transgenic plants with enhanced salinity tolerance phenotypes. OsRFPH2-3-overexpressing plants exhibited low Na+ accumulation and Na+/K+ ratios in their roots. Theses results suggest that overexpression of OsRFPH2-3 can make plant insensitivity about salinity conditions.

• 한국환경과학회지
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• 제18권12호
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• pp.1361-1368
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• 2009

The effects of $Cd^{2+}$ ions on the Chl a fluorescence of 5 hydrophytes (e.g. Lemna, Salvinia, Ricciocarp, Nymph, Typha plants) were investigated in order to select $Cd^{2+}$-sensitive plant species and to get informations on physiological responses of plants to $Cd^{2+}$ stress. Lemna plants were most sensitive to cadmium stress, while Nymph plants were tolerant. However, in all $Cd^{2+}$-treated plants, Fv/Fm, the maximum photochemical efficiency of PS II, decreased in proportion to the increase of $Cd^{2+}$ concentration and treatment time. The Chl a fluorescence transient O-J-I-P was also considerably affected by $Cd^{2+}$ ions; the fluorescence yield decreased consid- erably in steps J, I and P in $Cd^{2+}$ treated plants, although it followed a typical polyphasic rise in non-treated plants. In Lemna plants, the functional parameters, ABS/CS, TRo/CS와 ETo/CS and RC/CS, decreased in proportion to the increase of $Cd^{2+}$ concentration, while N, Mo and Kn increased. The structural parameters, ${\Phi}po$, ${\Phi}po$/($1-{\Phi}po$), Plabs, SFlabs, Kp and RC/ABS, also decreased according to the increase of $Cd^{2+}$ concentration. Consequently, Lemna plants will be useful as a experimental model system to investigate responses of plants. And several functional or structural parameters could be applied to determine quantitatively the physiological states of plants under stresses.

• 한국작물학회지
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• 제31권4호
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• pp.440-446
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• 1986

열대 및 아열대지역의 대두재배에서 수량을 격감시키고 있는 콩녹병에 대한 내병성품종과 이병성품종을 공시하여, 본 병해의 진전과정과 생리적 및 수량관련형질에 미치는 영향을 검토한바 그 결과를 요약하면 마음과 같다. 1. 이병성품종은 내병성품종에 비하여 병의 조기감염 및 진전이 빨랐으며, 녹병에 의한 낙엽은 콩 꼬투리가 반정도 등숙된 후부터 급격히 증가하였다. 2. LAI의 감소는 이병성품종이 내병성품종에 비하여 빨랐으며, 건전개체와 녹병 이병개체간의 엽녹소함양의 차리는 내병성품종에서 2.04%, 이병성품종에서 16.43%의 차이가 있었다. 3. 지상부 건물중은 녹병무발병구(살균제 처리구)에서는 계속 증가하였으나, 녹병발병구에서는 R$_{6}$ 생육단계 이후부터 감소하였고, 감소정도는 이병성품종이 내병성품종에 비하여 더 컸다. 4. 협과 종실의 건물중은 이병성품종의 녹병무발병구에서는 R$_{6}$생육단계 이후에 급격히 증가하였으나, 녹병발병구에서는 아주 완만하게 증가하였고, 내병성품종에서는 녹병의 영향을 적게 받아 녹병발병구에서 계속 큰 폭으로 증가하였다. 5. 녹병은 불완전립과 빈 꼬투리 수를 증가시키고, 종실의 Oil 함양 및 길이, 폭, 두께를 감소시키며, 협수, 입수, 백립중을 감소시켜 수량을 격감시키지만 단백질 함양에는 영향을 미치지 않았다. 6.수량에 대한 녹병의 영향은 내병성품종에서 22.3%, 이병성품종에서 68.7%의 수양감소가 있었다.

• 한국농림기상학회지
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• 제5권1호
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• pp.6-10
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• 2003

본 연구는 층층나무를 대상으로, 엽 내에서 측정한 MDA 함량을 기준으로 오존 내성 개체를 선발하고자 수행하였다. 또한 각종 오염물질에 대한 내성을 평가 하기 위해 MDA 함량을 이용하는 것이 타당한지를 검토하고자 하였다. 실험에 사용된 층층나무는 오대산(5본), 치악산(5본), 점봉산(5본), 주왕산(1본), 태백산(1본), 지리산(5본), 소리봉(5본), 속리산(4본), 소백산(4본), 계방산(4본) 등 9개 지역에서 채취한 종자를 이용하였으며, 오존 처리는 100 ppb에서 하루 8시간 씩 10주 동안 실시하였다. 오존 처리가 종료된 후, 층층나무의 수고와 MDA 함량을 측정하였고, 수고와 MDA 함량간의 관계를 분석 하였으여, 수고와 MDA 함량의 표준화 지수를 이용하여 오존에 대한 내성그룹, 중간그룹, 민감성그룹을 각각 30개체씩 선발하였다. 오존 처리된 층층나무의 수고와 MDA 함량은 가계간, 지역간 차이를 보여주었으며, MDA 함량은 수고생장과 역상관(r=-0.531, p$\leq$0.001)을 나타냈다. 개체별 수고와 MDA 함량을 기준으로 선발한 층층나무는 내성그룹과 민감성 그룹간 수고와 MDA 함량 차이가 뚜렷하였다. 따라서 MDA 함량은 오존에 대한 내성 및 민감성을 구분하는데 유용하게 이용될 수 있을 것으로 판단된다.