• 한국연초학회지
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• 제17권1호
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• pp.20-26
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• 1995

This study was carried out to obtain the basic data which include the change of the photosynthetic rate and protein content according to growth stage in the process of senescence of tobacco plant The photosynthetic rate was the maximum with 26.31$\mu$mol.CO2/m2.sec and stomatal resistance was the minimum with 0.2552cm/sec at 15th days after leaf emergence. However, after 50 days the photosynthesis was very little occurred. During leaf developments the number of chloroplast was increased and reached at the maximum at 25th days after emergence of leaf, thereafter, it was decreased gradually. The content of protein increased continuously and showed the highest value at 15th days after leaf emergence. The degradation rate of soluble protein was more rapid than that of insoluble protein at early stage of senescence. The range of decrement in the insoluble protein was low at late stage of senescence. The content of Rubisco, the key enzyme of photoamthesis, corresponded to about 50% of soluble protein and reached to the maximum at 150 days after leaf emergence. As the senescence progressed, the content of large subunit(UV) of Rubisco showed a tendency to decrease more rapidly than that of small subunit(SSU). The total amount of amino acids was the highest at 15th days after leaf emergence.

• 한국환경과학회지
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• 제26권5호
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• pp.601-608
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• 2017

The effects of elevated atmospheric $CO_2$ on growth and photosynthesis of soybean (Glycine max Merr.) were investigated to predict its productivity under elevated $CO_2$ levels in the future. Soybean grown for 6 weeks showed significant increase in vegetative growth, based on plant height, leaf characteristics (area, length, and width), and the SPAD-502 chlorophyll meter value (SPAD value) under elevated $CO_2$ conditions ($800{\mu}mol/mol$) compared to ambient $CO_2$ conditions ($400{\mu}mol/mol$). Under elevated $CO_2$ conditions, the photosynthetic rate (A) increased although photosystem II (PS II) photochemical activity ($F_v/F_m$) decreased. The maximum photosynthetic rate ($A_{max}$) was higher under elevated $CO_2$ conditions than under ambient $CO_2$ conditions, whereas the maximum electron transport rate ($J_{max}$) was lower under elevated $CO_2$ conditions compared to ambient $CO_2$ conditions. The optimal temperature for photosynthesis shifted significantly by approximately $3^{\circ}C$ under the elevated $CO_2$ conditions. With the increase in temperature, the photosynthetic rate increased below the optimal temperature (approximately $30^{\circ}C$) and decreased above the optimal temperature, whereas the dark respiration rate ($R_d$) increased continuously regardless of the optimal temperature. The difference in photosynthetic rate between ambient and elevated $CO_2$ conditions was greatest near the optimal temperature. These results indicate that future increases in $CO_2$ will increase productivity by increasing the photosynthetic rate, although it may cause damage to the PS II reaction center as suggested by decreases in $F_v/F_m$, in soybean.

• 한국환경과학회지
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• 제26권10호
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• pp.1147-1153
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• 2017

To maintain a rich biological diversity is important to develop for biomaterial resources such as Korean evergreen broad-leaved tree species, the distribution of which is restricted to the southern part of Korean peninsula. We assessed photosynthetic characteristics of Quercus acuta and Castanopsis sieboldii, the representative evergreen broad-leaved trees in Korea, in order to establish a basis for conservation strategy related to distributional change in evergreen broad-leaved tree species according to climate change. Photosynthetic characteristics were evaluated in the sun and shade leaves of the two species. Sun leaves in both species revealed higher light compensation point and maximum photosynthetic rate compared to the shade leaves. In addition, photosynthetic rate was higher in Q. acuta than C. sieboldii, which was supported by a higher leaf nitrogen content and leaf mass per area. Water use efficiency was also higher in Q. acuta as compared to that in C. sieboldii. Similar photosynthetic rate, however, was shown in photosynthetic response to $CO_2$ concentration in the intercellular space. These results suggest that both species could respond differently to the changing environmental factors including climate change, suggesting the possibility of distributional changes resulting from a differential growth rate.

• 한국조경학회지
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• 제41권6호
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• pp.140-146
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• 2013

본 연구는 휴대용 광합성측정장치(CIRAS-2, PPS, UK)를 이용하고, 토양 수분조건에 따른 섬기린초의 생리특성을 파악하였다. 섬기린초의 광합성 속도, 식물수분이용효율, 호흡속도 등 측정을 통하여 섬기린초의 생장에 가장 적합한 광도와 토양 수분범위를 명확하게 파악하였다. 광도에 따른 광합성 속도가 증가하였고, $600{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$ 경우에서 최고점에 도달한 후 그 이후 감소하는 경향을 나타났다. 토양 수분 조건에 따른 섬기린초의 광합성 속도과 식물수분이용효율은 수분함량 11.31%에서 가장 높은 값을 보였으며, 호흡속도는 수분함량 7.91%에서 가장 높은 값을 나타냈다. 그 결과에 의하면, 섬기린초는 가장 적합한 광도 범위가 $600{\sim}1,200{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$이고, 수분 범위가 7.09~11.31%이다.

• 한국작물학회지
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• 제29권2호
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• pp.186-190
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• 1984

참깨의 재배환경 차이에 따른 광합성능력의 변화를 검토코저 참깨의 품종별, 파종기에 따른 광합성과 재식거리, 차광정도 잎의 부위별 광합성을 측정한바, 다음과 같은 결론을 얻었다. 1. 참깨의 품종간에는 개화전에는 단경형의 풍년깨가 광합성이 높았으나, 개화기부터는 반대로 분지형의 광산깨가 높았으며, 생육시기별로는 파종후 3주가 가장 높았다. 2. 차광정도별 광합성능력은 파종후 4주에는 70% 차광구를 제외한 35%, 55%차광구 모두 무차광과 비슷하였으나, 개화시부터는 무차광>35%> 70%차광 순으로 차광정도가 높을수록 광합성은 저하되었다. 3. 참깨의 잎부위별 광합성은 파종후 10일 (본엽3교)에는 중위엽>상위엽>하위엽 순으로 광합성이 높았으나, 파종후 3주이후부터는 잎의 부위는 높을수록 광합성이 높았다. 4. 파종후 6주까지는 재식거리에 따라 광합성의 차이가 없었으나, 6주후부터는 60${\times}$15cm> 50${\times}$10cm>40${\times}$7.5cm의 순으로 소식일수록 광합성이 높았다.

• 한국작물학회지
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• 제33권4호
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• pp.350-352
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• 1988

This study was carried out to know the influence of turbidity of submerged water on photosynthetic rate of rice plant after water submerging treatment. Rice plants were transplanted in the pot at maximum tillering stage and they were sumberged for 3days at meiotic stage, 20days after transplanting, in the plastic container which had the clear and turbid water temperature adjusted around 24 to $25^{\circ}C$. Photosynthetic rate at 6 hours recovery after submergence was 41.5 to 54.2% compared to the control, but in the case of cultivar 'Nagdongbyeo', it was rapidly increased by 97.3 to 104.6% in the clear water and by 68.6 to 77.5% in the turbid water at 2 to 4 days recovery after submergence. Photosynthetic rates per plants at 6 hours to 4 days recovery after submergence were 128.3 to 245.5 $C_2$ mg.hr.$^{-1}$, in 'Samgamgbyeo' and 71.1 to 162.4 $CO_2$, mgㆍhr.$^{-1}$ in 'Nagdongbyeo' Photosynthetic rate to respiration ratio of rice plant recovery after submergence was lower compared to control plant and it was lower in 'Nagdongbyeo' than that in 'Samgangbyeo'.ngbyeo' than that in 'Samgangbyeo'.gangbyeo'.pos;.

• 한국약용작물학회지
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• 제26권2호
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• pp.181-187
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• 2018

Background: This study aimed to investigate out the influence of drought stress on the physiological responses of Dendropanax morbifera seedlings. Methods and Results: Drought stress was induced by discontinuing water supply for 30 days. Under drought stress, photosynthetic activity was significantly reduced with decreasing soil water content (SWC), as revealed by the parameters such as Fv/Fm, maximum photosynthetic rate ($P_{N\;max}$), stomatal conductance ($g_s$), stomatal transpiration rate (E), and intercellular $CO_2$ concentration (Ci). However, water use efficiency (WUE) was increased by 2.5 times because of the decrease in $g_s$ to reduce transpiration. Particularly, E and $g_s$ were remarkably decreased when water was withheld for 21 days at 6.2% of SWC. Dendropanax morbifera leaves showed osmotic adjustment of -0.30 MPa at full turgor and -0.13 MPa at zero turgor. In contrast, the maximum bulk modulus of elasticity ($E_{max}$) did not change significantly. Thus, Dendropanax morbifera seedlings could tolerate drought stress via osmotic adjustment. Conclusions: Drought avoidance mechanisms of D. morbifera involve reduction in water loss from plants, through the control of stomatal transpiration, and reduction in cellular osmotic potential. Notably photosynthetic activity was remarkably reduced, to approximately 6% of the SWC.

• 환경생물
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• 제30권3호
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• pp.210-218
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• 2012

일반적으로 많이 양식되는 방사무늬김(Porphyra yezoensis Ueda)에 대하여 방사무늬김 엽체의 형태적 특성, 탄소 및 질소 성분의 농도, 안정동위원소 비값, 광합성 효율을 방사무늬김 양식이 이루어 지고 있는 남서해역에서 조사를 하였다. 방사무늬김의 형태적 특성에 대해서 살펴보면 평균 엽장은 11.6~16.3 (13.8) cm, 평균 엽폭은 4.6~6.3 (5.4) cm이었고, 단위면적당 방사무늬김 엽체의 평균 엽중량은 $1.1{\sim}2.6(1.86)g\;DW\;m^{-2}$이었다. 단위면적당 Chl a 농도는 2.18~17.77 (평균 9.65) mg DW Chl a $m^{-2}$이었다. 방사무늬김의 탄소 농도는 $201{\sim}317(240)mg\;DW\;g^{-1}$이었고, 질소 농도는 $39.8{\sim}50.0(43.5)mg\;DW\;g^{-1}$이었으며, C/N비는 5.0~6.7 (5.5)이었다. 방사무늬김의 방사성 안정동위원소비 중에서 탄소 안정동위원소 비는 ${\delta}^{13}C$=-25.6‰ 에서 ${\delta}^{13}C$=-24.0‰ (평균 -24.7‰)의 값을 보였고, 질소 안정동위원소 비는 ${\delta}^{15}N$=1.3‰ 에서 ${\delta}^{15}N$=4.1‰ (평균 2.1‰)의 값을 보였다. PAM에 의한 해조류의 광합성 특성은 광합성 활동의 지시자로서 사용될 수 있다. 우리는 Diving-PAM을 이용하여 각 정점 해조류인 방사무늬김의 광합성율을 분석하였다. 최대양자수율은 0.46~0.55 (평균 0.52)로서 최대 양자수율의 변동은 정점간 큰 차이는 없었다. 최대상대전자전달률은 4.71~5.84 (평균 5.33) ${\mu}mol\;electrons\;m^{-2}\;s^{-1}$ 로서 최대양자수율과 비슷한 분포를 보였다. 기울기 (${\alpha}$)는 0.027~0.045 (평균 0.036)을 보였고, 전자전달을 위한 포화광은 지역에 따라서 일부 차이를 보였으나 $139{\sim}180(156){\mu}mol\;photons\;m^{-2}\;s^{-1}$이었다. 남서해역 방사무늬김 엽체의 탄소 및 질소 농도와 광합성 효율은 지역에 따른 큰 차이는 보이지 않았다. 광합성 특성은 낮은 최대양자수율과 최대 상대전자전달률로 인한 낮은 광합성 효율이 나타났다.

• 한국자원식물학회지
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• 제11권1호
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• pp.86-92
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• 1998

The photosynthetic rate (LPS)in the field was higher in the non-shading condition than in the shading. The fertilizer application was somewhat higher than non-fertilizer application. After humus application at 50% sading condition the growth and LPS increased with Ligularia fischeri. The maximum LPS at 80% shading was 22.3${\mu}{\textrm}{m}$mol/m/s with N-fertilizer application . Except Aster tataricus and Solidago virge-aurea. var. asiatic where the maximum LPS at non-shading and N-fertilizer application were 38.68 and 35.28${\mu}{\textrm}{m}$mol/m2/s. While the maximum LPS of Aster scaber was 30.01${\mu}{\textrm}{m}$mol/$m^2$/s at non-shading and non-fertilizer application. the growth rate was higher shading and fertilized conditions than non-shading and non-fertilized . The most effective shading condition was 50% , but leaf ration was highest in the 80% . But a. tataricus was favorable at non-shading and N-feritlized conditions.

• 한국약용작물학회지
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• 제20권5호
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• pp.320-330
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• 2012

This study was conducted to investigate the changes of chlorophyll contents, chlorophyll fluorescence, photosynthetic parameters, and leaf growth of Synurus deltoides under different shading treatments. S. deltoides was grown under non-treated (full sunlight) and three different shading conditions (Shaded 88~93%, 65~75%, and 45%~55%). Light compensation point ($L_{comp}$), dark respiration ($D_{resp}$), maximum photosynthesis rate ($Pn_{max}$), photo respiration rate ($P_{resp}$), carboxylation efficiency ($\Phi_{carb}$), and photochemical efficiency were decreased with increasing shading level; However, $CO_2$ compensation point ($CO_{2\;comp}$), total chlorophyll content, and specific leaf area (SLA) were shown the opposite trend. S. deltoides under 88~93% treatment showed the lowest photosynthetic activity such as maximum photosynthetic rate ($Pn_{max}$), photochemical efficiency, and $CO_2$ compensation point ($CO_{2\;comp}$). Therefore, photosynthetic activity will be sharply decreased with a long period of 8~12% of full sunlight. With the shading level decreased, carotenoid content and non-photochemical fluorescence quenching (NPQ) increased to prevent excessive light damage. This result suggested that growth and physiology of S. deltoides adapted to high light intensity through regulating its internal mechanism.