• Journal of Plant Biotechnology
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• v.4 no.4
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• pp.171-178
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• 2002

Chlorophyll (Chl) fluorescence imaging was used to investigate the effectiveness of in vivo incorporation methods for two chemicals, 3-(3',4'-dichlorophenyl)-1,1-dimethylurea (DCMU) and methyl viologen (MV) in rice, a monocot, and cucumber, a dicot, leaves. four different methods (vacuum infiltration, floating, transpiration-aided incorporation through petiole and spraying) were compared, and $F_i$ and $F_v$/$F_m$ were chosen for the imaging of the DCMU- and MV-treated leaves, respectively. The effects of the chemicals in plants were generally heterogeneous over the whole leaf area. Moreover, the effectiveness of the treatment of a chemical in plant leaves was dependent on chemical species, plant species, concentration of the chemical, the treatment method, the duration of the treatment, the existence of light and detergent, etc. In conclusion, we suggest that to achieve the proposed effects of chemicals in plants for an actual experiment, these factors must be considered before the chemical treatment, and the best method for the treatment of the chemicals tested was floating and vacuum infiltration in the dicot and the monocot leaves, respectively, as drawn from Chl fluorescence imaging analysis.

• Journal of Plant Biology
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• v.39 no.2
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• pp.113-121
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• 1996

The role of Ca2+ on benzyladenine (BA)-induced senescence retardation in mature wheat (Triticum aestivum L.) primary leaves was investigated. When an extracellular calcium chelator, ethylene glycol-bis-($\beta$-aminoethylether)-N, N'-tetraacetic acid (EGTA) together with BA, was applied to senescing leaves for 4 days of dark incubation, the content of chlorophyll and soluble protein decreased rapidly. And, the content of malondialdehyde (MDA), known to be a degradation product of membrane lipids, increased compared with the BA alone control. The BA-EGTA combination also caused the stimulation of protease and RNase activity and a rapid loss of catalase activity owing to the decling of BA effects. In the case of treatment with only intracellular calcium antagonist 3, 4, 5-trimethoxybenzoic acid 8-(diethylamino) octyl ester (TMB-8) without the BA addition, the chlorophyll content at day 4 after dark incubation decreased in paralled with the increasing concentration of the antagonist. In addition, the chlorophyll content at 10-5 M calcium ionophore A23187 treatment in the absence of BA was similar to that of the BA alone treatment. These results suggest that calcium may mediate the retardation effect of BA on leaf senescence by acting as a second messenger and that the calcium input from cell organelles, as well as the calcium inflow from intercellular spaces and cell walls, may be involved in modulating cytosolic calcium levels related to BA action.

• Journal of Ecology and Environment
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• v.33 no.3
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• pp.195-204
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• 2010

In the study, the effects of elevated $CO_2$ and temperature on the photosynthetic characteristics, chlorophyll content, nitrogen content, carbon content, and C/N ratio of Phytolacca insularis and Phytolacca americana were examined under control (ambient $CO_2+$ ambient temperature) and treatment (elevated $CO_2+$ elevated temperature) for 2 years (2008 and 2009). The photosynthetic rate, transpiration rate and water use efficiency of two plant species were higher under the treatment than the under the control. The stomatal conductance of P. insularis was higher under the control, but that of P. americana was not significantly affected by $CO_2$ and temperature under the treatment. The chlorophyll contents of two species were decreased about 72.5% and 20%, respectively, by elevated $CO_2$ and temperature. The nitrogen contents of two species were not significantly altered by increase in $CO_2$ and temperature. The carbon contents of the two species were higher under the treatment than under the control. The C/N ratio of P. insularis was higher under the treatment but that of P. americana was not significantly affected by $CO_2$ and temperature. These results demonstrated that the physiological responses of P. insularis native plants might be more sensitively influenced by a $CO_2$-mediated global warming situation than those of the P. americana invasive plants.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.27 no.6
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• pp.727-732
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• 1994

In the South Sea of Korea, in vivo fluorescence intensity (IVF) and extractable chlorophyll a concentration were measured to determine whether there was significant defference in in vivo fluorescence per unit chlorophyll a (R) between netplankton and nanoplankton size classes (less than $22{\mu}m$). IVF and chlorophyll a were linearly related for both size classes, but R's were significantly different between two size classes. The R of nanoplankton was about 7 times higher than that of netplankton. Therefore, the size dependency of R must be taken into consideration when size fraction of phytoplankton biomass is determined from the measurements of in vivo fluorescence intensity.

• Journal of Photoscience
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• v.1 no.1
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• pp.47-52
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• 1994

Effects of HgCl$_2$-treatment on electron transport, chlorophyll a fluorescence and its quenching were studied using isolated barley (Hordeum vulgare L. cv. Albori) chloroplasts. Depending on the concentration of HgCI$_2$, photosynthetic oxygen-evolving activities of photosystem II (PS II) were greatly inhibited, whereas those of photosystem I (PS I) were slightly decreased. The inhibitory effects of HgCl$_2$ on the oxygen-evolving activity was partially restored by the addition of hydroxyamine, suggesting the primary inhibition site by HgCl$_2$2-treatment is close to the oxidizing site of PS tl associated with water-splitting complex. Addition of 50 $\mu$M HgCI$_2$ decreased both photochemical and nonphotochemical quenching of chlorophyll fluorescence. Especially, energy dependent quenching (qE) was completely disappeared by HgCl$_2$-treatment as observed by NH$_4$CI treatment. In the presence of HgCI$_2$, F'o level during illumination was also increased. These results suggest that pH gradient across thylakoid membrane can not be formed in the presence of 0 $\mu$M HgCl$_2$. In addition, antenna pigment composition might be altered by HgCl$_2$-treatment.

• Ocean Science Journal
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• v.41 no.3
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• pp.181-189
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• 2006

Frontal areas between warm and saline waters of the Kuroshio currents and colder and diluted waters of the East China Sea (ECS) influenced by the Changjiang River were identified from the satellite thermal imagery and hydrological data obtained from the Coastal Ocean Process Experiment (COPEX) cruise during the period between March $1^{st}$ and $10^{th}$, 1997. High chlorophyll concentrations appeared in the fronts of the East China Seas with the highest chlorophyll-a concentration in the southwestern area of Jeju Island (${\sim}2.9\;mg/m^3$) and the eastern area of the Changjiang River Mouth (${\sim}2.8\;mg/m^3$). Vertical structures of temperature, salinity and density were similar, showing the fronts between ECS and Kuroshio waters. The water column was well mixed in the shelf waters and was stratified around the fronts. It is inferred that the optimal condition for light utilization and nutrients induced both from the coastal and deep waters enhances the high phytoplankton productivity in the fronts of the ECS. In addition, the high chlorophyll-a in the fronts seems to have been associated with the water column stability as well.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.46 no.2
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• pp.134-138
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• 2001

This experiment evaluates wintering ability to maintain green color of lawn grasses during winter and investigates the effects of top dressing of fertilizer on improving green color during regrowth. Kentucky blue-grass could maintain green color and leaf chlorophyll content better than tall fescue and creeping bentgrass in winter. All three grasses in this experiment have shown the excellent wintering ability. In enhancing the recovery of green color at the early stage of regrowth, the mulching effect with rice straw was highly significant for creeping bentgrass. Green color recovery in grasses during its regrowth was better at the top dressing plots than at the plots without top dressing, but when fertilizer application levels were increased, green color in lawn grass did not significantly change. Although green color in tall fescue, Kentucky bluegrass, and Korean lawngrass could be maintained during summer, the green color of creeping bentgrass is reduced significantly with high temperature. Top dressing after winter and mowing improved leaf chlorophyll content and green color in tail fescue and Kentucky bluegrass significantly. However, Korean lawngrass did not respond significantly with increased levels of fertilizer.

• Journal of the Korean Professional Engineers Association
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• v.18 no.2
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• pp.16-22
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• 1985

This study was carried out to evaluate the quality of soybean sprouts grown under three different sources of light. The soybean was germinated under light through blue (251 ux), red (751 ux) and white (50 to 200 lux) polyethylene films at 25$^{\circ}C$ for 10hr./day. Vitamin C, chlorophyll, cellulose and total protein contents were determined and texture was evaluated by tasting soybean sprouts soup. protein pattern in the soybean sprouts were investigated using polyacrylamide gel electrophoresis. Vitamin C, chlorophyll and cellulose contents were increased by white light intensity. The texture of the sprouts grown under white light (50 lux, 100 lux) was better than darkness, but fought under 200 lux. Vitamin C contents of soybean sprouts grown under various sources of light (in order of light : blue > white > red) were higher than theses of ones grown in the darkness. Biosynthesis of chlorophyll was not correlated to Vitamin C content. Total protein contents of cotyledon was not changed significantly under light irradiation. But the soybean sprouts grown under different quality of light, hypocotyl was higher than those grown darkness. (37% and 20% higher for blue light and white light) Densitometric tracing of disc polyacrylamide gel electrophoretic patterns showed that protein of hypocotyl under white light had more high molecular weight protein.

• Proceedings of the KSRS Conference
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• v.1
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• pp.475-478
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• 2006

Total primary production resulting from the photosynthetic process can be defined as the amount of organic matter produced in a given period of time. It is proportional to the chlorophyll-a (chl-a) values in the surface layer of the ocean. The MODIS board on Aqua satellite measures visible and infrared radiation in 36 wavebands, providing simultaneous images of chl-a concentration and sea surface temperature (SST) in the upper layer of the sea. The seasonal distribution of chl-a concentration during one year from April 2005 to March 2006 was examined. Light has a role of starting the seasonal cycle. The Kuroshio Current in this area induces many oceanographical features affecting to the change of seasonal control. The chl-a concentration is also seasonal, which is low in summer and high in winter. In summer, the meandering of Kuroshio Current induces strong eddies and increases the chl-a concentration. In autumn, the delayed small autumn bloom occurred until last December due to the Kuroshio Current. When the Kuroshio axis moves far from the coast, the coastal water dominates and increases the concentration even in the winter. The spring bloom starts early at the beginning of March and decreases during the spring.

• Journal of Ginseng Research
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• v.8 no.1
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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.