• Korean Journal of Environmental Biology
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• v.22 no.1
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• pp.233-241
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• 2004

Chlorophyll fluorescence and antioxidative enzyme activity were investigated from leaves of Crinum asiaticum var. japonicum under the natural condition in winter, in order to monitor plant response and physiological states such as vitality, productivity and so on. In the O-J-I-P transients, the fluorescence intensity of J, I, P-step decreased remarkably depending on temperature drop in winter. The photochemical efficiencies of PSII, Fv/Fm, were significantly low in late winter with decrease of Fm. These results indicate that Crinum plants were affected by seasonal drop of temperature. The catalase activity significantly decreased depending on temperature drop in winter. However, the activity of superoxide dismutase ascorbate peroxidase and peroxidase slightly increased in winter while some isoenzymes appeared in winter. These results, with the remarkable decrease of Ev/Fm in winter, represent that Crinum plants were exposed to oxidative stress and subsequently damaged leading to cell death.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.18 no.2
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• pp.105-118
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• 2015

This study was conducted to obtain proper amount of solid swine manure and poultry manure in the beginning phase of Cornus kousa growth by investigating the initial germination, seedling growth increment, dry weight, chlorophyll content change, body nutrient uptake and chemical changes of soil according to the concentration of solid swine manure and poultry manure fertilization. When treated with solid swine manure and poultry manure, seed germination rate was the highest in the control. However germination rate showed a tendency to decrease when treated with high concentration of swine manure and poultry manure. The survey results of the growth increment were all higher than that of the control. At the 1.0% treatment of both swine and poultry manure, the seedling height growth was highest. Poultry manure treatment made higher result than swine manure treatment at each treatment. Dry weight was the highest at the 1.0% treatment by both swine and poultry manure. Dry amount declined sharply at the 2.0% treatment. Poultry manure was higher in weight than swine manure at every treatment. Chlorophyll content was the highest at the 1.0% treatment by both swine and poultry manure, but declined sharply at the 2.0% treatment. The survey content was higer than that of the control. The amount of nutrients absorbed in the seedling body was generally high at the 1.0% treatment of swine manure and poultry manure. For the planting soil of Cornus kousa the higher concentration of swine manure and poultry manure was, the lower pH became. However, nitrogen, got higher. available phosphoric acid, exchangeable K, Na, and Mg got higher.

• Research in Plant Disease
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• v.16 no.1
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• pp.81-85
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• 2010

Arabidopsis seedlings subjected to low pH stress in the range of pH 5.6-4.0 did not show significant retardations in root and shoot growths. Treatment of pH 3.5-2.5 resulted in significant reductions in root and shoot length, especially in roots. Chlorophyll contents in seedlings increased during acid treatment of pH 5.6-4.0, but decreased by stronger acid treatment of pH 4.0 and lower pHs. Total carotenoid contents showed similar trend to chlorophyll contents by increasing during pH 5.6-3.5 treatments and decreasing by pH 3.0-2.5. Anthocyanin contents increased under acid stress of pH 5.6-3.0 and showed great reduction at pH 2.5. The ratios of carotenoids/chlorophylls and anthocyanins/chlorophylls increased by acid stress treatments. That indicates plants try to adjust physiologically to acid stress and protect chlorophylls by increasing carotenoid and anthocyanin contents. However, different responses of chlorophylls and anthocyanins to acid stress indicate both pigments play different roles in protecting plant from acid stress.

• 한국해양학회지
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• v.27 no.2
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• pp.137-144
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• 1992

Picoplankton in the size range of $0.2-2.0{\;}\mu\textrm{m}$ were enumerated in the Nakdong River estuary on 17 October, 1991 by using an epifluorescence microscope. Numerous minute cells emitting yellow to orange fluorescence at various strengths were recognized and the cells were moistly spherical in shape. Picocyanobacteria seem to comprise most of the picoplankton observed. They also occurred in very polluted water. Cell densities of picoplankton were in the range of $683-3,878{\;}cells{\cdot}ml^{-1}$ at the surface water. In vertical profiles, the Numbers were maximum at subsurface and minimum at surface layer. Percentage picoplankton biomass determined by chlorophyll ranged from undetectable levels to 5.9% of the total chlorophyll. The cell density and chlorophyll a concentrations of picoplankton were relatively low in the study area compared to those of other locations in world ocean, but the study of picoplankton may be important in understanding of microbial food web in the sea.

• Journal of the korean society of oceanography
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• v.33 no.4
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• pp.157-167
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• 1998

The distribution of particulate organic carbon and nitrogen (POC and PON) and chlorophyll a of particulate organic matter was investigated in the southwestern East Sea in August and October 1995. The upwelled 'cold water mass' with temperature less than 14$^{\circ}$C occurred near the Campo coast in August. At most of the onshore stations, concentrations of POC and PON were high in surface water, rapidly decreased with depth down to 30 m and then remained constant. Differences in their concentrations between surface and bottom waters were larger in August than in October. At the offshore stations, POC and PON were higher in surface than in deep waters though the differences in concentration were small. The highest, vertically integrated inventories of POC, PON and phytoplanktonic carbon in the upper mixed waters of the onshore stations occurred in August. The mixed layers at onshore stations showed relatively high percentages of POC, PON and chlorophyll a in total suspended matter, low ratios of POC to chlorophyll a and high inventories of phytoplanktonic carbon, compared with the values at offshore stations. These phenomena were more obvious in August, when cold water mass developed strongly, than in October. These results indicate that primary production plays a significant role for the budget of particulate organic matter in the upwelled cold water mass of the southwestern East Sea.

• The Korean Journal of Ecology
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• v.19 no.2
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• pp.151-163
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• 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.

• KSBB Journal
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• v.8 no.2
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• pp.115-121
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• 1993

The effect of polyamine on chlorophyll amount, chloroplast peroxidase and chloroplast thylakoid protein in rice leaf segments which were grown for 10 days(16 hrs, light : 8 hrs, dark) in a hormone-free MS medium containing polyamine was studied. Polyamine treatment increased the chlorophyll contents compared with the control in rice leaf segments. Especially spermine was most effective. Also, in rice leaf segments treated with polyamine chloroplast peroxidase activity was higher than in the control. The treatment with lmM of spermidine increased the enzyme activity by 100%. In polyamine treatment and control two major polypeptide bands corresponding to 56 and 25Kd molecular weight were clearly resolved with other minor bands by SDS-PAGE in the insoluble protein fraction. However, in these bands (56, 25Kd), the total area of protein in treating with polyamine were higher than that of the control. These results suggest that polyamine was an important factor in the chloroplast development of rice seedlings.

• Ocean and Polar Research
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• v.34 no.2
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• pp.201-218
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• 2012

The purpose of this study is to investigate climatological variations from the sea surface temperature (SST), chlorophyll-a concentration (Chl-a), and phytoplankton size class (PSC), using NOAA AVHRR, SeaWiFS, and MODIS data in the South Sea of Korea (SSK) and East China Sea (ECS). 26-year monthly SST and 13-year monthly Chl-a and PSC data, separated by whole and nine-different areas, were used to understand seasonal and inter-annual variations. SST and Chl-a clearly showed seasonal variations: higher SST and Chl-a were observed during the summer and spring, and lower values occurred during the winter and summer. The annual and monthly SST over 26 years increased by $0.2{\sim}1.0^{\circ}C$. The annual and monthly Chl-a concentration over 13 years decreased by $0.2{\sim}1.1mg/m^3$. To determine more detailed spatial and temporal variations, we used the combined data with monthly SST, Chl-a, and PSC. Between 1998 and 2010, the inter-annual trend of Chl-a decreased, with decreasing micro- and nano-size plankton, and increasing pico-size plankton. In regional analysis, the west region of the study area was spatially and temporally correlated with the area dominated by decreasing micro-size plankton; while the east region was less sensitive to coastal and land effects, and was dominated by increasing pico-size plankton. This phenomenon is better related to one or more forcing factors: the increased stratification of ocean driven by changes occurring in spatial variations of the SST caused limited contributions of nutrients and changed marine ecosystems in the study area.

• Journal of Korean Society of Forest Science
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• v.97 no.6
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• pp.680-689
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• 2008

This present study was conducted to investigate photosynthetic responses and chlorophyll fluorescence performances of Cornus controversa, Fraxinus rhynchophylla, Betula schmidtii, Prunus leveilleana, and Acer mono seedlings growing under four different light intensity regimes (full sun, and 65~72%, 29~40%, 7~12% of full sun). As result, Cornus controversa, Fraxinus rhynchophylla, and Betula schmidtii showed outstanding photosynthetic capacities in full sun and showed low shade tolerance. Prunus leveilleana showed good photosynthetic capacity in three treatment levels except for 7~12% of full sun and showed common shade tolerance. While, Acer mono showed good photosynthetic capacity and chlorophyll fluorescence in 29~40% of full sun. Acer mono showed the highest shade tolerance compared to the other four species.

• Korean Journal of Medicinal Crop Science
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• v.17 no.3
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• pp.187-191
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• 2009

This study was conducted to assess the response of LED (Light-emitting diode) irradiation on the growth characteristics and saponin contents of Panax ginseng C. A. Meyer. LED irradiation showed a positive effect for most of the parameters studied. The content of chlorophyll a in leaves was increased by 4.9$\sim$36.5%, under LED and fluorescent light conditions compared to the control. The content of chlorophyll b was also increased by 44.4$\sim$55.6% under blue and red LED compared to the control except under the red plus blue LED condition. The shoot and root weight were increased by $20\sim60%$ and $14.8\sim59.3%$, respectively under LED and fluorescent light conditions compared to the control. The total saponin content was increased by 1.8% under blue LED compared to the control, while total saponin content was decreased by 8.8$\sim$11.5% under red LED, red plus blue LED and fluorescent light conditions.