• 한국패류학회지
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• 제29권4호
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• pp.291-301
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• 2013

This study researched and compared the sedimentation environment and photosynthetic pigments at Gomso (GS) -bay, Yoja (YJ) -bay and KangJin (KJ) -bay in May, 2012. It was shown that KJ-bay consist of C (clay) and M (mud), and GS-bay consists of Zs (silty sand) and Sz (sandy silt). Averagely, IL of YJ-bay was 4.98%, KJ-bay 6.10%, and GS-bay 1.45%. As for COD concentration, there were no places that exceeded Japanese sediment contamination standard 20 mg/g-dry. As for AVS concentration, in case of KJ-bay, two places exceeded Japanese sediment contamination standard 0.2 mg/g-dry. If we look into the average C/N ratio of bays, YJ-bay showed 8.50, KJ-bay 6.60, and GS-bay 5.52, thus all of them showed the characteristic of oceanic origin. As for the plankton make-up classified by photosynthetic pigments, diatom was dominant, and both ratios of pigment and C/chlorophyll. a showed the relatively lower distribution at GS-bay than at KJ-bay and YJ-bay. It is judged that this is related to the characteristic of flow-in, and it implies that predation process and decomposition by organic matters actively occurs at YJ-bay and KJ-bay.

• 생물환경조절학회지
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• 제16권3호
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• pp.217-221
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• 2007

다양한 활엽수 자원의 개발에 필요한 기초자료를 제공하고자 쪽동백나무 유묘의 생육밀도에 따른 물질생산량과 생장특성 등 최적의 생장조건을 조사하였다. 묘목의 생육밀도는 수고생장에 크게 영향을 미치는 중요한 요인이 될 수 있으며, 본 실험 결과 쪽동백나무의 $1m^2$당 생육 밀도에 따른 묘목의 생장은 49본구에서 간장과 근원직경이 우수한 생장량을 보인반면 생육밀도가 낮은 처리구는 근원직경 생장이 증가하면서 간장생장은 떨어지는 경향을 보였다. 물질생산량 또한 생장 특성과 마찬가지로 $1m^2$당 49본구 처리구에서 전체 물질생산량이 통계적으로 유의적인 차이를 보이면서 $3.12{\pm}0.80g$로 다른 처리구보다 높은 물질생산량을 보였고, T/R율에서도 1.59로 나타났다. 생리적 특성으로 광합성률 또한 쪽동백나무의 경우 $1m^2$당 $49/m^2$ 본구와 $64/m^2$ 본구에서 상대적으로 높은 광합성률을 보였고 밀도가 높아질수록 광합성 효율이 떨어지는 결과를 나타냈다. 이는 생육 환경조건에서 적절한 공간 확보가 궁극적으로 최종 물질대사 작용인 광합성률 변화에서 최적의 상태를 보이면서 생리적으로 안정된 생장형태를 보이는 것으로 판단되며, 적정 공간의 장애가 실질적인 생장저하를 발생시키고, 궁극적으로 물질대사의 최고 단계인 광합성효율 또한 낮아지는 경향을 나타냈다.

• Journal of Crop Science and Biotechnology
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• 제11권1호
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• pp.75-82
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• 2008

Functional stay-green is a beneficial trait that may increase grain yield through the sustained photosynthetic competence during monocarpic senescence in cereal crops. The temporal changes of photosynthesis and related characteristics throughout the grain filling period of a stay-green japonica rice "SNU-SG1" was compared in growth chamber conditions with three high-yielding cultivars(HYVs) and their $F_1$ hybrids with SNU-SG1. SNU-SG1 exhibited a typical characteristic of functional stay-green in terms of chlorophyll degradation and photosynthetic competence during grain filling. According to the photosynthesis-light response curve measured at 10 and 35 d after heading for the flag leaf, SNU-SG1 exhibited higher initial light conversion efficiency and thus higher gross photosynthetic rate at light saturation compared to HYVs. Light saturation point was not different among genotypes, ranging from 1000 to 1500 ${\mu}mol$ photon $m^{-2}s^{-1}$. Net photosynthetic rate at light saturation($P_{max}$) of the upper four leaves in SNU-SG1 was much higher and sustained longer throughout grain-filling than HYVs and $F_1$ hybrids. The sustained high photosynthetic competence of SNU-SG1 during grain filling was ascribed to the longer maintenance of high mesophyll conductance that resulted from not only high chlorophyll content and its delayed degradation but also the slow degeneration of photosystem II(PS II) as judged by chlorophyll fluorescence($F_v/F_m$) of flag leaves. $F_1$ hybrids showed slow degeneration of photosystem II similar to the male parent SNU-SG1 while chlorophyll degradation pattern close to female parents, thus exhibiting a little higher $P_{max}$ than female parents. These results suggest that SNU-SG1 has a typical functional stay-green trait that can be utilized for increasing rice yield potential through the improved dry matter production during grain filling.

• Journal of Ecology and Environment
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• 제30권2호
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• pp.187-193
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• 2007

Higher plants can be categorized as C3, C4 or CAM according to their photosynthetic pathways, and some succulent plants are known to shift their patterns of photosynthesis from C3 to CAM in response to environmental stresses such as salt treatment or water deficiency. To investigate fundamental photosynthetic patterns and the induction of pattern shifts (C3, CAM, C3-CAM etc.) as a result of environmental stresses, we measured the water content, diurnal changes in pH, net $CO_2$ exchange, transpiration rate, total ionic contents, and osmolality of Kalancoe daigremontiana, Sedum kamschaticum and Sedum sarmentosum which belong to Crassulaceae known as representative CAM plant, after 10 days of drought treatment. S. kamschaticum and S. sarmentosum did not show a significant difference in diurnal pH variation in the treatment and control conditions. However, the pH of drought-treated Kalancoe was low at night and high in the daytime, with a pH value between 4 and 5. Typical CAM plants display a net $CO_2$ exchange that increases at night and decreases in the daytime. Kalancoe displayed the predicted pattern. However, S. kamschaticum and S. sarmentosum showed a photosynthetic pattern more typical of C3 plants, and did not show changes in photosynthetic pattern under drought stress. Kalancoe also showed a transpiration rate typical for CAM pho-tosynthesis, whereas the transpiration rates of S. kamschaticum and S. sarmentosum were in the typical range for C3 photosynthesis. Kalancoe had high total ionic contents during the night, which decreased somewhat during the daytime, whereas S. kamschaticum and S. sarmentosum displayed the opposite pattern. This result is similar to the diurnal patterns of changes in pH in the three plant species, which suggests a relationship between pH and ionic contents. S. sarmentosum showed lower osmolality under drought stress than in the control condition, whereas the osmolality of Kalancoe and S. kamschaticum did not differ between conditions. S. sarmentosum may have maintained internal water content by lowering its osmolality and raising its total ionic contents. In conclusion, Kalancoe displayed the characteristic responses of a typical CAM plant, whereas S. kamschaticum and S. sarmentosum displayed aspects of the C3 photosynthetic pattern under drought conditions. These results suggest that S. kamschaticum and S. sarmentosum (Crassulacea) in Korea overcome drought stress by increasing solute and ionic contents internally rather than changing their photosynthetic pattern from C3 to CAM under drought stress.

• 한국환경과학회지
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• 제17권4호
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• pp.469-477
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• 2008

The aerobic photosynthetic bacterium, which produces bacterial carotenoids was isolated and identified from coastal marine environments. This bacterium was identified by 16S rDNA sequencing and designated as Erythrobacter longus SY-46. E. longus SY-46 was Gram negative and rod shape, and the optimal culture conditions were $25^{\circ}C$, pH 7.0, and 3.0% NaCl concentration, respectively. The carbon and nitrogen sources required for the optimal growth were lactose and tryptone, respectively. Fatty acid compositions of E. longus SY-46 were $C_{18:1}$(78.32%), v-linolenic acid($C_{18:3n9.12.15c}:3.83%$), margaric acid($C_{17:0}$: 3.38%), palmitic acid($C_{16:0}$: 3.07%), and docosahexaenoic acid($C_{22:6n3}$: 2.21%). In addition, E. longus SY-46 showed the characteristic absorption peaks of bacterial carotenoids(in the region of 450 to 480 nm) and bacteriochlorophyll(770 to 772 nm). Major carotenoids of E. longus SY-46 were polyhydroxylated xanthophylls such as fucoxanthin and zeaxanthin.

• 생물환경조절학회지
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• 제17권2호
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• pp.101-109
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• 2008

인위적인 토양내 수분처리 결과 물푸레나무와 들메나무 모두 6월<8월<9월로 갈수록 엽록소 함량이 증가하였다. 생육기간이 지나는 동안 엽록소 a는 0.89mg/g에서 1.67mg/g로, 엽록소 b는 0.18mg/g에서 0.44mg/g을 나타냈으며, 두 수종 모두 6월보다 8월과 9월에 높은 함량 증가를 보였다. 두 수종의 광합성율을 보면, 물푸레나무는 각 토양수분 처리구마다 광합성율의 차이를 보였으며, 충분한 토양수분처리구($90{\sim}78%$)의 묘목이 상대적으로 낮은 토양수분조건에서 자란 묘목보다 높은 경향을 나타냈다. 들메나무 역시 물푸레나무와 비슷한 경향을 보였으며, 토양수분이 높을수록 광합성률이 높게 나타났고, 감소할수록 광합성률이 감소하였다. 광합성율의 생육시기별 변화는 두 수종 모두 9월>8월>6월 순으로. 9월에 상대적으로 높은 광합성률을 나타냈다. 이로 미루어보면 두 수종은 생장시기에 상관없이 수분함량이 높은 처리구에서 광합성이 활발히 이루어지는 것으로 생각된다.

• Molecules and Cells
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• 제41권3호
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• pp.161-167
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• 2018

Chloroplasts are present in organisms belonging to the kingdom Plantae. These organelles are thought to have originated from photosynthetic cyanobacteria through endosymbiosis. During endosymbiosis, most cyanobacterial genes were transferred to the host nucleus. Therefore, most chloroplast proteins became encoded in the nuclear genome and must return to the chloroplast after translation. The N-terminal cleavable transit peptide (TP) is necessary and sufficient for the import of nucleus-encoded interior chloroplast proteins. Over the past decade, extensive research on the TP has revealed many important characteristic features of TPs. These studies have also shed light on the question of how the many diverse TPs could have evolved to target specific proteins to the chloroplast. In this review, we summarize the characteristic features of TPs. We also highlight recent advances in our understanding of TP evolution and provide future perspectives about this important research area.

• 생물환경조절학회지
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• 제21권2호
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• pp.147-152
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• 2012

자생지별 꼬리진달래의 생리반응을 측정한 결과 광보상점은 석포리 11.8 ${\mu}mol\;m^{-2}\;s^{-1}$, 연하리 11.5 ${\mu}mol\;m^{-2}\;s^{-1}$, 월악산 10.4 ${\mu}mol\;m^{-2}\;s^{-1}$로 나타났으며, 광포화점은 500~600 ${\mu}mol\;m^{-2}\;s^{-1}$ 범위로 나타나 음수의 생리적 특성을 갖고 있었다. 광포화시의 광합성 능력은 석포리 5.5 ${\mu}mol\;m^{-2}\;s^{-1}$, 연하리 5.4 ${\mu}mol\;m^{-2}\;s^{-1}$, 월악산 5.6 ${\mu}mol\;m^{-2}\;s^{-1}$로 나타나 광보상점과 광포화점, 광합성 능력은 자생지별로 유의적인 차이가 나타나지 않았다. 온도 변화에 따른 자생지별 꼬리진달래의 순광합성 속도는 3지역 모두 20~$30^{\circ}C$ 온도역에서 높은 광합성 속도를 유지하는 것으로 나타났으며, 그 중 $25^{\circ}C$에서 가장 활발한 광합성을 하는 것으로 나타났다. 연하리의 수분이용효율이 석포리와 월악산에 비해더 높은 것은 포화광도에서 낮은 기공증산속도로 인한 결과였으며, 꼬리진달래의 자생지별 엽록소 a, b 및 총 엽록소 함량은 유의적차이가 없는 것으로 나타났다. 위의 결과를 통해 꼬리진달래는 음수의 특성을 가지며, 생육에 적합한 온도는 20~$30^{\circ}C$인 것을 알 수 있었다.

• 한국조경학회지
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• 제21권1호
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• pp.139-148
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• 1993

The present experiments have been conducted to find out the plant's growth environments habitate, mode of life, characteristic of photosynthesis, habit of growth and propagation. The results of this study are as follows: 1. Sambucus williamsii var. Coreana distributes around all sides of native site without having any relation to altitude, inclination and direction. 2. In the native site, Robinia pseudo - acacia and its neighboring species were Prunus yedoensis, Acer pseudo-sieboldianum, Lindera obtusiloba and Staphylea bumalda. From 21 to 41 types of species were located in the vegetation of the quadrat area. 3. According to the variation of leaf temperature with the result of the change of net photosynthetic rate, the optimum temperature for growth is $25^{\circ}C$. 4. The rooted rate of vegetative propagation was the highest at 100ppm IBA plot and the lowest at 200ppm BA plot. 5. The rooted rates of Sambucus williamsii var. coreana in perlite 50% bed, vermiculite bed and peatmoss 50%+sand 50% bed are higher than others.

• 한국농림기상학회지
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• 제4권1호
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• pp.12-17
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• 2002

여수산업단지 같은 대기오염지역에서 채취한 사방오리나무의 질소고정 뿌리혹의 접종 효과를 보기 위해서 오염에 대해서 저항성 개체와 민감한 개체를 선발하고 종자를 채취한 후 파종을 하고 발아한 후 3주 후의 유묘를 같은 지역에서 채취한 뿌리혹으로 12개의 조합으로 접종을 하였다. 접종효과를 비교하기 위해서 광합성 능력을 측정하였다. 대기오염에 대해 저항성을 보이는 모수에서 채취한 종자가 민감한 개체에서 채취한 것보다 광합성 능력이 높은 경향을 나타냈다. 대기오염에 민감한 모수에서 채취한 뿌리혹으로 접종한 조합이 일반적으로 생리활성이 낮았다. 그러나 접종효과는 뿌리혹을 채취한 모수보다는 종자를 채취한 모수가 어떤 상태인가에 따라서 광합성 능력이 더 영향을 많이 받는 것으로 나타났다. 그렇기 때문에 생리적인 특성에 대한 영향은 뿌리혹을 채취한 모수보다는 종자의 모수가 더 중요한 요인 같다.