• 한국약용작물학회지
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• 제16권6호
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• pp.416-420
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• 2008

This study was conducted to investigate the influence of shading material on the chlorophyll fluorescence, photosynthesis, transpiration, stomatal conductance and its any correlations in Panax ginseng C.A.Meyer. Fo was higher in polyethylene shade net than in silver-coated shading plate, but this treatment caused a lower Fm in comparison with silver-coated shading plate. Also, Fv/Fm and PhiPS2 showed higher in silver-coated shading plate than in polyethylene shade net. The relationship between net photosynthetic rate and transpiration, stomatal conductance were increased as the PAR (Photosynthetic active radiation) was increased and reached maximum at the $200-400\;{\mu}mol/m^{2}/s$ of PAR in all of leaves, and the higher in silver-coated shading plate than in polyethylene shade net. A linear equation was obtained between net photosynthetic rate and transpiration, net photosynthetic rate and stomatal conductance. SPAD was higher in silver-coated shading plate than in polyethylene shade net.

• 한국환경농학회지
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• 제20권3호
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• pp.186-191
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• 2001

PSO (petroleum spray oil) 살포가 감귤잎에 미치는 광합성 관련 생리적 영향을 밝히고자 4 년생 온주밀감(궁천조생)에 PSO를 살포한 후 광합성, 증산량, 기공전도도 및 엽록소형광 등의 변화에 관하여 검토하였다. 시험은 (1)PSO 0.33% 및 1.0% 농도별 처리, (2)다른 주야간 온도처리($34/24^{\circ}C$, $30/20^{\circ}C$ 및 $28/16^{\circ}C$)하에서의 PSO 처리, 그리고 (3) PSO 처리후 일시적인 고온($50^{\circ}C$, 10시간) 처리 등 3개로 나누어서 실시하였다. 그 결과, PSO를 처리하면 감귤 잎에 유침상이 발생하는데 처리후 $30{\sim}40$일후에는 무시해도 좋을 정도로 사라졌다. 0.33% PSO 처리시에는 광합성, 증산량 및 엽색도 등에 별 영향이 없으며, 1% 처리시에는 기공전도도, 증산율, 광합성속도 등이 저해되다가 살포 20일 후에는 회복되는 경향을 나타냈다. 온도 처리별 PSO 처리의 영향은 고온구 $(34/24^{\circ}C)$에 1.0% PSO를 처리했을 경우, 처리 7일 이후에 엽록소 형광(Fv/Fm) 값이 저하하였다. 또한 PSO 처리후 인위적으로 고온($50^{\circ}C$, 10시간)처리를 하였을 경우, 1.0% PSO와 디치를 혼용처리한 나무의 낙엽이 현저하게 증가하였으며, 남은 잎에서도 생리적 형질의 저해가 인정되었다. 이러한 결과 0.33% PSO 처리에서는 감귤 잎의 광합성 관련 특성에 별 영향이 없으나, 1.0% PSO 이상의 살포의 경우 한동안 일부 생리적 기능의 저해를 보였으며, 고온조건이거나 디치와 같은 약제와 혼용할 경우에는 생리적 기능저해가 더욱 심해지는 것으로 나타났다.

• Journal of Plant Biology
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• 제34권3호
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• pp.215-221
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• 1991

Photoxynthetic properties of polyvinylalcohol (PVA)-immobilized chloroplast especially regarded to stability of photosynthetic electron transport and the fluorescence induction pattern were studied. When isolated spinach chloroplasts were immobilized with PVA, it showed good preservation of photosynthetic electron transport activity, especially PS II activity, during storage at -15$^{\circ}C$, 4$^{\circ}C$ and 2$0^{\circ}C$. And immobilized chloroplasts revealed similar thermostability of whole chain electron transport to free chloroplsts. And the absorption peak of red band of chloroplasts showed the blue-shift of 2-4 nm after immobilization. Fv/Fm ratio of chlorophyll fluorescence slightly decreased after immobilization. White light pulse after continuous light do not induced the additional fluorescence rise. This means chlorophyll fluorescence at room temperature reached to Fmax under continuous light in the immobilized chloroplasts. It seems that PVA may be a good candidate for immobilization matrix for the preservation of photosynthetic function of thylakoids and for the continuous use of chloroplast membranes of higher plants for solar energy storage and conversion.

• Journal of Photoscience
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• 제7권2호
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• pp.39-44
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• 2000

To examine the chilling tolerance lipids, we compared the chilling susceptibility of photosystem II of wild type tobacco plants with that of transgenic tobacco plants, in which the sensitivity to chilling had been enhanced by genetic modification of fatty acid unsaturation of chloroplast membrane lipids. The transgenic tobacco plants were found to contain reduced levels of unsaturated membrane fatty acids by being tansformed with cDNA for glycerol-3-phosphate acyltransferase from squash. For the purpose of studying on the functional integrity of photosystem II during low-temperature photoinhibition, the photochemical efficiency was measured as the ration of the maximun fluorescence of chlorophyll (Fv/Fm) of photosystem II. In parallel with an investigation on the transgenic plants, susceptibility of chilling-resistant species, such as spinah and pea, and of chilling-sensitive ones, such as squash and sweet potato, to low-temperature photoinhibition was also compared in terms of room temperature-induced chlorophyll fluorescence from photosystem II. When leaf disks from the two genotypes of tobacco plants were exposed to light at 5$^{\circ}C$, the transgenic plants showed more rapid decline in photochemical activity of photosysytme II than wild-type plants. When they were pretreated with lincomycin, an inhibitor of chloroplast-encoded protein synthesis, the extent of photoinhibition was even more accelerated. More impottantly, they showed a comparable extent of photoinhibition in the presence of lincomycin, making a clear contrast to the discrepancy observed in the discrepancy observed in the absence of lincomycin. Restoration of Fv/Fm during recovery from low-temperature photoinhibition occurred more slowly in the transgenic tobacco plants than the wild-type. These findings are discussed in relation to fatty acid unsaturation of membrane phosphatidylglycerol. It appears that the ability of plants to rapidly regenerate the active photosystem II complex from might explain, in part, why chilling-resistant plants can toleratlow-temperature photoinhibition.

• 한국환경농학회지
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• 제39권2호
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• pp.138-141
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• 2020

BACKGROUND: Fresh weight is one of the major quality measurement factors in determining the quality of fresh fruits. A practical method has been developed for rapid and non-destructive measurement using the Chlorophyll Fluorescence Image (CFI) technique to estimate changes in fresh weight of post-harvest products. METHODS AND RESULTS: Kiwifruit (Actinidia deliciosa) was used and measured for the fresh weight and CFI under different temperature conditions at 0, 10, and 20℃, from 0 to 21 days after storage (DAS). We observed the fresh weight of kiwifruit and measured the surface image for determining F_v/F_m value in terms of maximum quantum yield on each day. To estimate freshness of kiwifruit we applied linear regression between the measured fruit weights and F_v/F_m values. Results showed that fruit weights were reduced by 4% at 0℃, 6% at 10℃, and 14% at 20℃ for 21 days, respectively. And also, the value of Fv/Fm was shown as decreasing trend at all temperature conditions, especially at 20 ℃. Fv/Fm values showed highly significant correlation (R²>0.9) with fresh weight of kiwifruit at all different storage temperatures. CONCLUSION: Thus, CFI technique can be useful to estimate the fresh weight of kiwifruit.

• 현장농수산연구지
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• 제18권1호
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• pp.71-78
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• 2016

여름철 토마토 시설 재배 시 CO₂ 시용에 의한 고온적응성 향상을 구명하고 그 가능성을 검토하고자 실시하였다. CO₂ 시용 농도별 엽록소 형광을 측정한 결과 Fm/Fo과 Fv/Fm은 1000ppm 처리가 타 처리에 비하여 높았으며, Fo은 낮았다. 이는 1000ppm의 CO₂ 처리는 다른 처리에 비하여 고온 적응성이 높았음을 보여 주고 있다. 동일한 기온 조건하(30℃, 40℃)에서 광합성률은 CO₂ 농도에 따라 증가하였으며, 고온상태인 40℃ 조건하에서도 1000ppm의 CO₂ 시용은 30℃ 조건보다 광합성률은 낮았으나 그 값은 약 18.5μmolm^-2s^-1이였다. 슈퍼 도태랑(모모타로), 미니 찰 두 품종 모두 CO₂ 농도가 높을수록 항산화 효소인 Superoxide Dismutase 와 Peroxidase의 활성은 높았다. 미니찰 품종에서 CO₂ 농도와 온도변화에 따른 엽록소 형광 Fo의 변화양상을 조사하여 고온한계 온도를 추정한 결과 500ppm은 41℃, 1000ppm은 43℃였다.

• 한국환경과학회지
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• 제6권4호
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• pp.369-378
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• 1997

The effects of various intensity of W-B on barley seeding were investigated by PS I and II activities and chlorophyll fluorescence. The Inhibitory effect of UV-B radiation on electron transport activity was Increased as the intensity of UV-B Irradiation was increased. Especially, PS I is more sensitive to UV-B radiation than PS I is. By the addition of uncle electron donor, DPC, to the chloroplasts of the barley seedlings treated with UV-B, the photoreduction of DCPIP was recovered by only 1 IBI on electron transport activity. However, the activity of PS II was Inhibited by 45% by the treatment with UV-B, but recovered it only 11% by the addition of DPC. These suggest that other sites besides the oxidation site of PS II may be affected more by UV-B Irradiation. As the intensify of UV-B was Increased, Fo was Increased while Fv was decreased, and thus Fv/Fm was decreased. This means that photochemical efficiency was reduced. With this parameters, it might be that UV-B radiation affected adversely to around PS II.

• Journal of Plant Biology
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• 제37권2호
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• pp.231-236
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• 1994

분리한 시금치 엽록체에 $Cd^{2+}$을 처리하였을 때 광계 I에 비해서 광계 II의 활성이 낮은 농도의 $Cd^{2+}$에 의해 억제되었다. 그러므로 $Cd^{2+}$에 의해 1차적으로 광계 II 활성이 저해되었다는 것을 알 수 있다. 광계 II의 전자공여체인 diphenylcarbazide를 첨가했을 때 대조구에 비해 활성이 크게 증가하였다. $Cd^{2+}$ 처리시 $Mn^{2+}과\;Ca^{2+}을$ 외부에서 첨가했을 때 광계 II 활성은 회복되었지만 회복되는 정도가 15%로 낮았다. $50\;\mu\textrm{M}\;Cd^{2+}$ 처리구에서 광계 II 활성은 크게 감소하였으나 Fv/Fm는 미소하게 감소하였으며 $100\;\mu\textrm{M}\;Cd^{2+}$ 처리구에서 Fv/Fm는 크게 감소하였다. 광계 I활성은 $Cd^{2+}$의 처리 농도가 증가함에 따라 감소하였으나 세척하였을 경우 0.2 mM의 $Cd^{2+}$ 처리구에서 대조구보다 활성이 증가하였으며 농도가 높아짐에 따라 활성의 회복 정도가 컸다.

• 한국자원식물학회:학술대회논문집
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• 한국자원식물학회 2002년도 제9차 국제심포지움 및 추계정기학술발표회
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• pp.68-68
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• 2002

아열대성 식물 4종 (문주란, Crinum asiaticum var. japonicum; 박달목서, Osmanthus insularis; 죽절초, Chloranthus glaber; 파초일엽, Asplenium antiquum)을 대상으로 자연 환경요인의 변화에 따른 엽록소형광을 분석하여 이들 식물의 활력도를 검토하였다. 여름철 일변화에 있어서 양지에 자라는 문주란과 박달목서는 Fv/Fm이 새벽과 밤에는 0.80~0.83 범위의 높은 값을 보이지만, 낮시간에는 0.65~0.73으로 낮았다. 1-qN과 1-qP도 낮시간에 크게 낮아졌다. 음지에 자라는 죽절초와 파초일엽의 Fv/Fm은 높아서 0.83~0.85 범위를 유지하였으며 일변화적 특성은 관찰되지 않았다. 1-qP의 변화는 거의 관찰되지 않았으나 1-qN이 낮시간에 다소 감소하는 경향을 보여주었다. 죽절초와 파초일엽에서는 광억제가 거의 일어나지 않으나 문주란과 박달목서에서는 낮시간의 고광에 의한 광억제가 나타난다. 하지만 여기에너지의 일부를 열의 형태로 방출하여 광피해를 완화시키고 있는 것으로 보인다. 겨울철에는 Fv/Fm이 모든 종에서 0.8 이하의 값을 나타내었는데, 특히 문주란의 Fv/Fm 값은 다른 3종 보다 더 낮았다. 그리고 모든 종에서 일변화적인 특성은 관찰되지 않았다. 문주란의 1-qN은 낮시간에 다소 감소하였지만, 나머지 3종의 식물은 높은 값을 나타내었다. 그리고 l-qP는 문주란과 박달목서에서는 낮시간에 0.6 범위로 낮아졌다. 이는 종에 따라 차이가 있지만 겨울철 저온의 영향을 받은 결과로 보인다. 한편, 여름철 문주란과 박달목서의 O-J-I-P곡선은 거의 유사하며 낮에 뚜렷하게 낮았고, 죽절초와 파초일엽에서는 일변화적 특성은 두드러지지 않았다. 그리고 P $I_{NO}$ 와 SF $I_{NO}$ 가 죽절초를 제외한 3종에서 여름철 낮시간에 증가하였다. 겨울철의 O-J-I-P곡선은 모든 종에서 낮시간에 다소 낮아지지만 큰 변화는 없었다. 그리고, 문주란, 박달목서, 파초일엽에서 $\psi$o/(1-$\psi$o)가 낮시간에 다소 증가하였다. 이로부터 P $I_{NO}$ , SF $I_{NO}$ , $\psi$o/(1-$\psi$o)등의 변수는 식물의 활력도를 검정하는 지표로 활용될 가능성이 높다고 할 수 있다.

• Journal of Plant Biology
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• 제34권4호
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• pp.303-309
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• 1991

Limitation of photosynthesis in detached Chinese cabbage (Brassica campestris L.) leaves was induced by feeding of mannose (25 mM) for 12 h in the light, and changes in the basic thylakoid functions under this condition were investigated. The acid soluble phosphate contend and CO2 uptake rate was decreased by 66% and 67%, respectively. However, the starch content was increased by 24% compared to those of controls. From the fast induction curves of chlorophyll fluorescence, dark level fluorescence (Fo) slightly increased while intermediate plateau fluorescence level (FI) to peak level fluorescence (Fp) transient was significantly decreased with a slight decrease in the Fo-to-FI transient. This data means that reduction of secondary electron acceptor of PSII (QB) might be more severely inhibited than that of primary electron acceptor of PSII (QA) by decrease in phosphate level. The strong decline of (Fv)m//Fm ratio suggests that efficiency of excitation energy capture by PSII was decreased markedly. The quenching of Fo (qO), an indicator of state transition, was also occurred over the slow induction kinetics of chlorophyll fluorescence. From quenching analysis, fluorescence was dominantly quenched by nonphotochemical quenchings (qE+qT). These results showed that the capture and transfer efficiency of excitation energy to PSII reaction center in thylakoid was decreased with the decline of leaf phosphate level, and that the state transition was occurred during the induction of photosynthesis under these conditions.