• Journal of Ginseng Research
• /
• 제22권2호
• /
• pp.102-113
• /
• 1998

This experiment used chlorophyll fluorescence techniques to assess the effect of irradiant during leaf development on photoinhibition of photosynthesis in Panax ginseng. Seedlings of p. ginseng were grown in the 91asshouse at four shade levels. The maximum mid-day irradiant in each treatment between emergence (January 4) and completion of the experiment (February 25) was 1220, 485, 235, 125 $\mu$mol/$\textrm{m}^2$/s. To assess the rapidity of photosynthetic readaptation to changes in light levels, fluorescence parameters (Fo, F, Fm, Fm', AF/Fm;, Fv/Fm) were measured for three days before and after transfer of plants (on February 21) from each light treatment into each of the other light treatments. Before transfer, dark adapted values of Fv/Fm in the 1220 (0.699) and 485 (0.739) treatments were different from each other and lower than values in the 235 (0.764) and 125 (0.768) treatments, indicating mild photoinhibition. Patterns of change in F during the day also differed between treatments, with low light treatments tracking irradiant levels, but F in the high light treatment (1220) declined in the morning, presumably due to fluorescence quenching. Although plants grown at high irradiant had relatively low photosynthetic efficiency, relative electron transport rate was greater than in lower irradiant treatments. After transfer, plants adopted the daily pattern of change in F of the treatment to which they were moved with little change in absolute levels of F, except in plants transferred from the highest (1220) to the lowest light level (125), where F increased over the course of the three days following transfer. After plants were transferred, Fm' converged on values similar to those in plants raised in the treatments to which they were moved. Values of Fv/Fm in plants moved from low to high light declined dramatically, but there was no decline in plants from 485 moved to 1220. Values of Pv/Fm in plants that were moved from high light to lower light increased to values above those recorded in plants raised in the lower light treatments. Reductions in quantum efficiency caused by photoinhibition at high irradiant may be more than compensated for by higher electron transport rates, although evidence suggests that under high irradiant this tends to be balanced by reduced leaf area and earlier senescence. Chlorophyll fluorescence techniques appear capable of indicating effects of irradiant induced stress in ginseng, yielding results comparable to those obtained with gas exchange techniques but in less time and with greater replication.

• 생명과학회지
• /
• 제32권10호
• /
• pp.743-748
• /
• 2022

부추는 아시아를 포함한 전세계적으로 분포하는 초본이다. 한국에서 부추는 양념용 채소와 국수용 고명에 사용된다. 질소비료, 인산비료, 칼리비료와 수분 스트레스가 부추(Allium tuberosum Rotter) 잎에 미치는 영향에 대해 조사하였다. 엽록소 a 함량은 10 mg/l 질소 비료에서 0.386였고, 50 mg/l에서는 0.584였다. 엽록소 a, b, 전체 엽록소량은 대조군에 비해 유의한 차이를 나타내었다(p<0.05). 엽록소 a, b, 전체 엽록소에 대한 피어슨 상관계수(Pearson's r)는 각각 0.940, 0.966, 0.971였다. 잎의 엽록소 a, b, 전체 엽록소는 인산비료인 경우 40 mg/l가 50 mg/l 시비보다 높았다. 인산 비료인 경우 10 mg/l에서 전체 엽록소량은 0.312였고 50 mg/l 일 때 0.589였다. 엽록소 효율과 습도와의 관계를 산출하였다. 광합성 효율의 척도로 기저 수준의 형광산율(Fo), 최대 형광산율(Fm), 전자소멸 상태(Fv), 최대 PSII 광계비율(Fv/Fm)의 기울기는 각각 -0.931, 0.972, 972, 0.950였다. 질소, 인산, 칼륨 비료와 가뭄스트레스는 부추의 엽록소함량과 효율성에 영향을 주었다.

• 한국환경과학회지
• /
• 제11권10호
• /
• pp.1023-1030
• /
• 2002

The effects on photosynthesis of NaCl(0, 0.2, 0.4, 0.6, 0.8 or 1.0 M) were examined in etiolated barley seedlings. Chlorophyll(Chl) a, Chl b and carotenoid contents, Chl a fluorescence and quenching coefficients of Chl fluorescence have been determined in the primary leaves of etiolated barley seedlings cultivated under low light(60 $\mu$㏖ $m^{-2}\;s^{-1}$). Chl a, b, and carotenoid contents were decreased remarkably in comparison with the control at 0.4 M NaCl. However, the value of Fo and Fv were decreased at 0.6 M NaCl and the ratio of Fv/Fm were deceased at 1.0 M NaCl. Chlorophyll synthesis was seriously inhibited from 0.4 M NaCl, and the photosynthetic electron transport system was inhibited from 0.6 M NaCl. Quantum of photosystem II reaction center was inhibited at 1.0 M NaCl. The effects of NaCl on the Chl content were raised in a 6 hrs, but the effects of NaCl on the value of Fo, Fv and Fv/Fm were raised in 30 hrs. The value of qP was decreased in comparison with the control at all concentrations, but there was a small change in the value qE. These results provide evidence that NaCl inhibited effects of various concentration of NaCl were inhibited quinone redox, however, proton gradient between thylakoid membranes was little damaged.

• 한국환경과학회지
• /
• 제13권12호
• /
• pp.1015-1021
• /
• 2004

This study was conducted to investigate the changes of chlorophyll contents and chlorophyll fluorescence in barley(Hordeum vulgare L.) 7 day old seedling treated with 0.2M, 0.4M, 0.6M, 0.8M, and 1.0M NaCI concentration containing Hepes buffer(pH 7.5). Barley was affected by NaCI treatment. The chlorophyll a, b and carotenoid of barley decreased with an increase in NaCI concentration. However, chlorophyll a, b and carotenoid of barley were not greatly influenced by o.8M and 1.0M NaCl. Fv, Fv/Fm and qP were gradually decreased by higher concentration of NaCI. qP, qNP, qR and qE were gradually decreased by 6hr. During barley chloroplast was development NaCI affected chlorophyll synthesis than photosynthetic activity. Whereas barley seedling leaves were more influenced photosynthetic activity than chlorophyll contents by NaCI.

• 원예과학기술지
• /
• 제32권2호
• /
• pp.142-148
• /
• 2014

Effect of silicon (Si) nutrition on growth and temperature stress tolerance of Nephrolepis exaltata 'Corditas' grown in a soilless substrate was examined. In vitro-grown acclimatized plantlets were transplanted into the pots containing a coir-based substrate. A nutrient solution containing 0, 50, or $100mg{\cdot}L^{-1}$ Si was supplied through a drip-irrigation system. After 5 months of cultiv ation, S i-treated and -untreated p lants were grown at 10, 25, or $40{\pm}1^{\circ}C$ under a 12 h photoperiod with $530{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$ PPFD and 60% RH. After 7 days, chlorophyll content and chlorophyll fluorescence parameters were measured. Silicon nutrition had a negative effect on growth characteristics of N. exaltata 'Corditas'. However, Si-treated plants had more tolerance to temperature stress than the control plants. The Fv/Fm value was not significantly different when the plants were exposed to $25^{\circ}C$. However, significant difference in Fv/Fm was recorded when plants were exposed to 10 or $40^{\circ}C$. Thus, Fv/Fm could be used as an indicator of low and high temperature tolerance in ferns. The present study also suggests that application of Si may be used to enhance temperature tolerance of ferns.

• 생명과학회지
• /
• 제18권2호
• /
• pp.154-161
• /
• 2008

염분에 대한 벼 유식물의 생리학적 광화학적 반응을 잎의 상대수분함량, 엽록소 형광 및 뿌리의 수분흡수를 통하여 연구하였으며, 벼 유식물이 농도가 다른 NaCl에 노출되었을 경우, 500 mM 이상의 농도와 4일, 5일간 스트레스를 준 처리구에서 식물체의 외관상 심각한 장해 징후가 나타났다. 500 mM에서는 5일간, 1,000 mM에서는 4일간 스트레스를 준 처리구와 NaCl를 처리하지 않은 대조구 간의 광합성 Fv/Fm에서 유의성이 있는 차이가 나타났으며, 그러나 뿌리 수분흡수에서는 Fv/Fm에 비해 스트레스 기간이 짧은 2일에서도 수분흡수의 차이가 나타나기 시작했다. NaCl에 노출된 식물에서 잎의 상대수분함량은 외부 염분의 농도가 증가하구 스트레스 기간이 길어짐에 따라 점차 감소하였다. 잎의 상대수분함량 결과에서 1,000 mM 농도로 1일간 처리된 경우(88%)와 비교했어 2일 이상 NaCl를 처리한 경우들(58-67%)에서 보다 낮은 수분함량을 보였다. NaCl 스트레스는 4일과 5일간 처리한 경우 etiolate된 벼 유식물의 광 유도 녹화과정에서 NaCl 농도가 증가함에 따라 직선적으로 심하게 억제하였다(각각의 $R^2$=0.812과 0.918). 염분 스트레스 기간과 NaCl농도가 증가되었을 때, NaCl의 농도가 같음에도 잎의 Fv/Fm보다는 뿌리의 수분흡수가 더 민감하게 반응하는 것으로 보아 잎에서의 장해보다는 뿌리에서의 반응이 먼저 일어나는 것으로 보인다.

• BMB Reports
• /
• 제29권5호
• /
• pp.398-404
• /
• 1996

Light-chilling effects were investigated in chilling-sensitive cucumber (Cucumis sativus L. cv. Ilmichungjang) and chilling-resistant pea (Pisum sativum L. cv. Giant) leaf discs in relation to possible damage in D1 protein. In both plants, dark-chilling did not cause any noticeable changes in (Fv)m/Fm and lincomycin did not affect the decrease in (Fv)m/Fm caused by light-chilling. This result suggests that the de novo synthesis of D1 protein did not occur actively during light-chilling. In pea light-chilled for 6 h. the decreased (Fv)m/Fm was partly recovered in the dark, and almost complete recovery was observed in the light. In cucumber light-chilled for 3 h. the reduced (Fv)m/Fm decreased further for the initial 2 h recovery process in the light regardless of the treatment of lincomycin and recovered very slowly. In both plant species, the treatment of lincomycin inhibited the recovery process in the light, but did not significantly inhibit the process in the dark. In cucumber leaves pulse-labeled with $[^{35}S]Met$, the labeled band intensities of isolated pigment-protein complexes were almost the same during the 6 h light-chilling, but significant decreases in band intensities were observed during the 3 h recovery period. This result suggests that the irreversibly damaged D1 protein was degraded during the recovery period. However, no noticeable changes were observed in the pea leaves during the 12 h chilling and 3 h recovery period. The polyacrylamide gel electrophoresis of the pigment-protein complexes showed that the principal lesion sites of light-chilling were different from those of room temperature photoinhibition.

• The Korean Journal of Ecology
• /
• 제19권2호
• /
• pp.151-163
• /
• 1996

To investigate the early symptoms of light-chilling, alterations of chlorophyll fluorescence transients were monitored in cucumber (Cucumis sativus L. cv. Ilmichungjang) leaves. During 24 h chilling, decreases in (Fv)m/Fm, qE and qQ, and an increase in Fo were observed. The chilling effects were not recovered at room temperature, and a significant increase in Fo was observed during the recovery period. After 6 h chilling, ‘dip’(D) level of the transients became obscure, and the negative slope after ‘peak’(P) disappeared. The first derivative (dFv/dt) of the fast fluorescence rise curve was used to obtain more accurate information about the changes in the transients. The maximal rate of the fluorescence increase in the D-p rise curve (Fr) has been the most frequently used chilling stress indicator. However, a correct value of Fr could not be measured when the D level became obscure. This problem was overcome by introducing a new indicator, HFr (dFv/dt at Fv = 1/2 (Fv)m), and HFr gave very similar values to Fr. To monitor the changes in curvature around D level, another new parameter, ${\Delta}S$(D-Fr), was also introduced. These three parameters decreased very sensitively during light-chilling. In addition, increases in these parameters were observed during the first 2 h chilling, but this increase in Fr was also observed in pea leaf discs dark-chilled for 15 min, suggesting that this very early change is a common response to chilling in both pea and cucumber leaves. Quenching coefficients were also very sensitive to chilling, especially qE. Discussion on the usage of these parameters as chilling stress indicators is given in the text.

• 한국환경과학회지
• /
• 제8권2호
• /
• pp.255-261
• /
• 1999

To investigate the effects of strong acidic electrolytic water on the chloroplast, barley leaves were treated with strong acidic electrolytic water(pH 2.5). And to investigate the effects of weak acidic electrolytic water on the chloroplast development, etiolated barley leaves were treated with weak acidic electrolytic water(pH 6.5) during greening period. Chl contents, Fo, Fv, and Chl fluorescence quenching coefficient in barley leaves were measured during and after treatment of acidic electrolytic water. The following results were obtained. Chl a, b, and carotenoid were decreased with treatment of strong acidic electrolytic water. Chl contents were significantly decreased than that of the control after 5 min. These results provide evidence that the strong acidic electrolytic water dissimilate the Chl and so that the value of Fo was slightly increased. The strong acidic electrolytic water damaged PS II because Fo was increased and Fv, Fm, and Fv/Fm ratio were decreased. qP, qNP and qE were decreased. On the other hand qI was increased than that of the control. But Chl content and Chl fluorescence patterns were a little changed as the pH increase over 4.0 Chl a, b, and carotenoid were increased with treatment of weak acidic electrolytic water during greening period. Chl contents were significantly increased than that of control after 12 hours greening. These results provide evidence that the weak acidic electrolytic water accelerated the chlorophyll synthesis. And the weak acidic electrolytic water accelerated PS II development because Fv, Fm, qP and Fv/Fm ratio were increased than that of the control.

• 한국작물학회:학술대회논문집
• /
• 한국작물학회 2017년도 9th Asian Crop Science Association conference
• /
• pp.205-205
• /
• 2017

An excess soil water condition is one of the major problems for the field crops growing in paddy fields because of their poor drainage and less availability for oxygen uptake which leads to adversely affect the photosynthesis. Therefore, the current study was undertaken with aim to investigate the effects groundwater level on the photosynthetic response of soy bean (Urum), red bean (Arari), sesame (Geonbaek), perilla (Dayu) after the transplanting to the lysimeter to investigate the plant-water relation and their effect on photosynthesis. The chlorophyll content of the crops according to the humid conditions of the soy bean, sesame and the perilla was found to be 5%, 6.89 % and 13.7% higher than that of the groundwater treated at 40cm, respectively. On the other hand, the chlorophyll content of adzuki bean decreased 6.6% from the groundwater level of 40cm, and the sorghum decreased by 5.7%. As a result of investigating the Fv / Fm value of groundwater, the adzuki bean at 20cm above groundwater was lower than that of groundwater by 40cm immediately before flowering. The Fv / Fm value of soy bean and sesame at 40cm above groundwater were lowered by flowering under groundwater 20 cm and Fv / Fm value of sorghum is increased at 40 cm treatment immediately before flowering while the Fv / Fm values of the perilla had no significant difference in comparison to those at 20 cm and 40 cm of groundwater. In the case of chlorophyll fluorescence reaction, it is known that the when the absolute value is closer to 0.82, the stress is considered less. As a result of comparing the numerical values of the crops, it was found that the sorghum was the most stressed followed by adzuki bean and sesame, while the soy beans and perilla was found on the average, as they received less stress.