• Journal of Photoscience
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• 제7권4호
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• pp.139-142
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• 2000

To examine applicability of some optical indices from reflectance to estimate photosynthetic light use efficiency, photosynthesis, and narrow band spectral reflectance were simultaneously measured at various intensities of light with mongolian oak leaves. Narrow band of the broad-band NDVI was better than photochemical reflectance index and simple ratio to estimate photosynthetic light use efficiency in this study. Changes in spectral reflectance were detected at several wavelengths (540nm, 690nm, 740nm, and 800nm) associated with physiological status of plant leaves that could be components for new optical indices.

• 한국약용작물학회지
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• 제2권1호
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• pp.86-94
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• 1994

인삼(人蔘)의 광합성(光合成)이 콩보다 낮은 원인(原因)을 밝혀 인삼(人蔘)의 수량증대(收量增大)와 육종(育種)을 위한 기초자료(基礎資料)로 삼고저 자경종(紫莖種) 2년생(年生) 인삼식물(人蔘植物)에서 분리(分離)한 잎을 재료(材料)로 광합성(光合成)과 수분함량(水分含量), 기공식도도(氣孔植導度), 그리고 수분(水分) potential을 조사(調査)하고 콩과 비교(比較)하였다. 1. 동일(同一)한 광도(光度)에서 광합성(光合成)은 인삼(人蔘)이 콩보다 작았으며 광합성(光合成)에 대한 포화광도(飽和光度)도 약 $30{\mu}E\;/\;m^2\;/\;s$로 콩의 약 $800{\mu}E\;/\;m^2\;/\;s$보다 낮았다. 2. 분리(分離)한 잎에서 광합성(光合成)은 인삼(人蔘)이 콩보다 빠르게 감소(減少)하였으며 $20^{\circ}C$에서보다 $30^{\circ}C$에서 더 빨랐다. 또한 광합성(光合成)이 정지(停止)하는 시간(時間)도 인삼(人蔘)잎이 콩잎보다, $20^{\circ}C$에서보다 $30^{\circ}C$에서 더 짧았다. 3. 잎의 수분감소(水分減少速度)는 인삼(人蔘)이 콩보다 느렸고 광합성(光合成)이 정지(停止)되는 수분함량(水分含量)은 인삼(人蔘)잎(약$70{\sim}71%$)이 콩잎$(50{\sim}63%)$보다 높았다. 4. 수분함량(水分含量)파 광합성(光合成)과는 인삼(人蔘)과 콩 모두 온도(溫度)에 무관(無關)하게 각각(各各) 고도(高度)의 정(正)의 상관(相關)이 있었는데, 광합성(光合成)은 동일(同一)한 수분함량(水分含量)에서 인삼(人蔘)이 콩보다작았다. 5. 기공식도도(氣孔傳導度)와 광합성(光合成)과는 인삼(人蔘)과 콩 모두 두 온도(溫度)$(20^{\circ}C,\;30^{\circ}C)$에서 무관(無關)하게 고도(高度)의 정(正)의 상관(相關)이 있었으며, $20^{\circ}C$에서는 인삼(人蔘)의 기공식도도(氣孔傳導度) 범위(範圍)$(40mmo1\;/\;m^2\;이하)$에서 인삼(人蔘)과 콩의 광합성양(光合成量)은 비슷하였다. 6. 수분(水分) potential 엽수분함량(葉水分含量)이 동일(同一)한 조건(條件)에서 콩보다 인삼(人蔘)이 낮았으며, 수분(水分) potential과 광합성(光合成) 및 기공식도도(氣孔傳導度)와는 고도(高度)의 정(正)의 상관(相關)이있었다. 7. 이상(以上)의 결과(結果)를 종합(綜合)해 볼 때, 인삼(人蔘)의 광합성(光合成)이 타식물(他植物)보다 낮은 것은 기공식도도(氣孔傳導度)와 수분(水分) potential이 낮은 것과도 밀접(密接)한 관계(關係)가 있을 것으로 생각된다.

• 한국작물학회지
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• 제60권3호
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• pp.266-272
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• 2015

등숙기 고온이 잎의 생리적 활력과 등숙에 미치는 영향을 알아보고자, 동안과 일품 두 품종을 등숙기에 고온 처리하여 등숙 형질을 분석하고, 잎의 광합성, 엽록소 함량 및 엽록소 a/b율 등을 알아보았다. 등숙기 고온($27{\pm}4^{\circ}C$)처리에서 두 품종 모두 등숙률, 완전립률, 천립중이 감소하였으나 일품은 동안에 비해 모두 감소율이 컸다. 엽록소 함량은 등숙초기 고온에서 적온보다 두 품종 모두 증가하였으며, 등숙중기이후 엽록소감소양상은 온도처리에 따른 차이가 없었다. 엽록소 a/b율은 고온에서 감소하였다가 출수후 15일 이후 증가하였으며 적온에서는 출수 이후 지속적으로 증가하였다. 잎의 단백질농도 변화는 고온에서 등숙초기 약간 높은 경향이었으나 이후 처리 간 차이없이 등숙후기까지 지속적으로 감소하였다. 최대 광합성량은 유숙기인 출수 후 14일에 고온이 적온보다 높았고 출수후 7일과, 등숙후기(출수후 34일)에는 유의한 차이가 없었다. 잎의 유리당 함량은 고온이 적온보다 낮았다. 결론적으로 등숙기 고온은 잎의 생리적 활력을 적온보다 오히려 증가 시켜 엽록소함량과 광합성율이 증가하였으므로, 고온에 의한 이삭의 등숙저하는 이삭으로의 전류나 전분축적기작 과정의 문제가 더 클 것으로 생각된다.

• 생물환경조절학회지
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• 제8권1호
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• pp.42-48
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• 1999

반결구 상추 ‘Omega’와 잎상추 ‘Grand Rapids’의 m 재배에서 배양액내 Ca : K 비율이 광합성, 증산, 생육 및 tipburn 발생에 미치는 영향을 밝히고자 실험을 수행하였다. 반결구 상추와 잎상추 두 종 모두 광합성은 Ca : K 비율 3:6과 4.5:4.5에서 높았으며, 기공 저항은 잎상추가 반결구 상추보다 낮았다. 증산율은 3:6의 Ca : K 비율에서 두 종 모두 가장 높았으며, 잎상추의 증산율이 반결구 상추보다 높아 종간 차이를 보였다. 엽위에 따른 증산율은 완전 전개잎에 비해 미숙잎에서 낮았는데, 이것은 미숙잎에서 tipburn 발생이 많은 것과 깊은 관계가 있는 것으로 보였다. Ca 결핍구인 Ca : K 비율 0:9처리는 두 종 모두 극단적인 생육 저하와 함께 tipburn이 100% 발생하였으며, 반결구 상추는 Ca : K 1.5:7.5 처리에서도 tipburn이 25% 발생하였으나, 잎상추에서는 나타나지 않았다 작물 생육은 Ca 결핍구를 제외한 두 종 모두 Ca : K 3:6 처리에서 가장 높았다. 배양액의 Ca과 K의 불균형은 기공저항과 확산저항을 높여 광합성과 증산의 감소를 유도함으로써 Ca 이동에 영향을 미친 것으로 보였다.

• The Korean Journal of Ecology
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• 제26권4호
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• pp.165-172
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• 2003

The objectives of this study were to examine the physiological responses to ozone and to measure ozone uptake rates of Betula species exposed to relatively high concentration of pollutants. At the end of the growing season, photosynthesis, pigments contents, antioxidants (SOD and GR) and ozone uptake rates were measured or estimated at the leaves of five Betula species (Betula costata, B. davurica, B. platyphylla var. japonica, B. schmidtii and B. ermanii) exposed to 100ppb ozone concentration. On the termination of the experiment, growth effects were determined by measuring leaf area and dry weights of leaf, stem and root. Ozone treatment showed the significant reduction the leaf area and dry weight of four Betula species, except for B. ermanii. Shoot / root (SR) ratio of five species represented two different types. SR ratio of B. costata and B. davurica were lower than control, in contrast, SR ratio of B. platyphylla var. japonica, B. schimidtii and B. emani, were higher than that of control. The photosynthetic responses of five species were different in responses to ozone exposure. Four species, except for B. emanii, maintained or increased the stomatal conductance, but B. emanii decreased both stomatal conductance and photosynthesis. SOD activities of five species decreased by the ozone exposure, especially B. ermanii showed the largest reduction, GR activities of B. platyphylla var. japonica and B. schmidtii increased, B. costata and B. emanii decreased. Instantaneous ozone uptake rate was the highest at the leaves of B. ermanii and B. costata, ozone uptake per seedling was the highest at the leaf of B. schmidtii and B. emanii. It was concluded that B. costata, B. davurica and B. platyphylla var. japonica, appeared the growth reduction and visible ozone injury, were sensitive species to ozone, and B. schmidtii with the increased antioxidant activity and B. ermanii without the growth reduction were relatively resistant species to high ozone concentration at the early growing stage.

• 한국약용작물학회지
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• 제23권1호
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• pp.43-48
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• 2015

This study was carried out in order to investigate the photosynthesis response and leaf characteristics of Peucedanum japonicum growing in forest farming. The experiment was performed by leaf mold (pine tree and chestnut tree) and shading levels (0%, 35%, 50% and 75% shading). Light relative intensity was 100% (full sunlight), 60.3% (35% shading), 35.1% (50% shading), and 17.4% (75% shading) respectively. Light response curves of pine-leaf mold and chestnut-leaf mold were the highest in control (full sunlight) and these were getting lower in the higher shading level. Photosynthesis capacity and light saturation point were indicated higher in chestnut-leaf mold within the same shading level. As the shading level increased, maximum photosynthesis rate decreased. And apparent quantum yield was not indicated statistically significant difference from all treatment. Leaf area, leaf length and leaf width were significant higher in 35% shading and control under chestnut-leaf mold in all treatment. As the shading level increased, LAR (leaf area ratio), SLA (specific leaf area) and SPAD value decreased in pine-leaf mold and chestnut-leaf mold. As a result of surveying the whole experiment, P. japonicum is judged better growth and higher yield by maintaining 35% shading (relative light intensity 60%) under chestnut-leaf mold in forest farming.

• 한국환경농학회지
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• 제19권2호
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• pp.166-170
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• 2000

본 연구는 우리 나라 콩 장려품종인 단원콩, 황금콩, 광안콩 등 3가지 품종을 대상으로 100mM NaCl 처리에 따른 30일 묘의 생육특성 및 광합성 반응을 조사하여 다음과 같은 결과를 얻었기에 보고하는 바이다. 주경장과 주경절수는 NaCl 처리로 감소하였으며, 엽면적 및 건물중 역시 크게 감소하였다. 품종간 차이는 그다지 크지 않았지만 황금콩이 다른 두품종보다 감소정도가 적은 것으로 나타났다. 잎, 줄기, 뿌리로 구분한 건물중 변화는 줄기의 건물중이 가장 크게 감소하였으며 다음이 잎, 뿌리 순으로 NaCl에 영향을 받았다. 비엽면적(SLA), 지상부와 지하부 비율(Shoot/Root), 잎과 지하부의 비율(Leaf/Root)은 황금콩이 처리간에 차이가 없었으나 나머지 두 품종은 NaCl 처리로 감소하였으며, 옆위별 잎 두께는 무처리는 옆위간에 큰 차이를 보이지 않았지만 100mM MaCl 처리는 일정한 경향을 보이지 않았다. 제 1엽과 2엽의 엽록소 함량의 경시적 변화는 무처리는 처리 후 15일째에 급격히 증가하였지만 NaCl 처리는 점차 감소하는 경향을 보였다. 제 2엽의 광합성 속도는 경시적으로 일정한 경향을 보였지만 NaCl 처리로 광합성 속다가 감소하였으며 처리 후 20일째에 가장 많이 감소하였다. 광합성 속도와 기공전도도 및 증산속도와의 관계는 유의한 상관이 인정되었다.

• Journal of Ginseng Research
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• 제8권1호
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• pp.65-74
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• 1984

This experiment was carried out to study the effects of light intensity and soil water regimes on the growth of ginseng seedling. The results were as follows: 1. The maximum light intensity and optimum temperature in 1,le photosynthesis of ginseng seedling were 10,000 lux and 23 $^{\circ}C$. Respiration rate was increased at high temperature. 2. Air and soil temperature under the shading were increased as the increase of light intensity but soil water contents were decreased as the increase of light intensity, whereas air and soil temperature were decreased as the increase of precipitation under the shade b5: soil water contents were increased as the increase of precipitation under the shade. 3. The higher the transmittance of the shade, the greater the specific leaf weight (S.L.W.) and stomatal density. In contrast, however, the contents of total chlorophyll, chlorophyll a and b, and stomatal length was decreased. There was no any significant difference light intensity of the a/b ratio of chlorophyll. 4. The highest photosynthesis was occurred in ginseng leaves grown under the shade 5% L.T.R. and net photosynthesis rates increased with increasing soil water contents. 5. Optimum condition for usable seedling yield were 5% L.T.R. and 3.3% precipitation under the shade. Useless seedling increased with increasing precipitation under the shade.

• 한국작물학회지
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• 제48권1호
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• pp.25-30
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• 2003

This research was conducted to compare the dry matter production and the yield productivity among nine soybean cultivars by measuring the photosynthetic ability of the middle and lower leaves at the flowering and the seed development stages. The leaf greenness(SPAD value) were ranged as 32-42 at the flowering stage. Also, They were ranged as 25-40 and 38-51 at the fifth leaf and the seventh leaf, respectively. The photosynthetic ability at the flowering and the seed development stage showed significant differences among soybean cultivars, and the photosynthetic ability at the seed development stage showed higher difference among cultivars than the flowering stage. The variation of the photosynthetic ability at the flowering and the seed development stage also was significant among cultivars. The light saturation point at the flowering stage was about 1500 $\mu$mol $m^{-2}$ $s^{-1}$ PAR, and the seed development stage was about 1000 $\mu$mol $m^{-2}$ $s^{-1}$ PAR. The photosynthesis showed the high negative correlation with the leaf area and the positive correlation with the leaf area ratio. Also, photosynthesis at seed development stage showed positive correlation with grain yields but there was not significant between photosynthesis and yields at flowering stage..

• 한국약용작물학회지
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• 제28권2호
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• pp.111-118
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• 2020

Background: Cnidium officinale is a medicinal crop sensitive to high temperature. It is necessary to develop environment control technology that can reduce environmental stresses such as high temperature. This study was conducted to develop technology for stable production of Cnidium officinale by reducing damage owing to high temperature by applying shading treatment of varying duration, and structure. Methods and Results: Black shading nets were used from May to September or November; shading structures such as pillar, flat roof, and tunnel type structures were installed. Environmental changes, rate of photosynthesis, and growth characteristics were investigated. The shading treatment reduced temperature by 3℃. The rate of photosynthesis and yield with shading treatment were higher by 134% and 127%, respectively, than those with full sunlight. The ratio of shading area ranged from 50% to 71% according to the type of shading structure. The effect of environmental control on growth varied depending on the type of shading structure. Conclusions: The shading treatment reduced damage owing to high temperature, shading rate of 55% - 75% was recorded between the period May - September, and the flat roof type shading structure was considered the most suitable among shading methods.