• KOREAN JOURNAL OF CROP SCIENCE
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• v.29 no.2
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• pp.186-190
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• 1984

Photosynthetic rate of sesame varieties was investigated under the different cultural environments such as planting density or light intensity. The photosynthetic rate of Pungnyeon, monoculm variety, was higher than that of Kwangsan before flowering stage, while it was vice versa after the flowering stage. The maximum rate of photosynthetic rate was obtained three weeks after planting. The effects of light intensity on photosynthetic rate four weeks after planting was not apparent when the light intensity was reduced to the level of 35% and 55%, respectively. However, when the light intensity was reduced to 75% of the normal light intensity, the photosynthetic rate was also greatly reduced. The Photosynthetic rate after the flowering stage was reduced in the order of normal light, 35% and 75%, respectively.

• Korean Journal of Plant Resources
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• v.21 no.5
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• pp.357-361
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• 2008

The photosynthetic characteristics of three Ligularia species, L. fischeri, L. fischeri var. spiciformis and L. stenocephala under-tree cultivated in Dunnae-myeon, Hoengsung-gun were measured and compared. Total mean photosynthetic rate increased with increasing the light intensity up to 2,000 PPFD. Mean photosynthetic rate of L. fischeri increased to maximum value of $21.1{\mu}mol\;CO_{2}m^{-2}s^{-1}$ with increasing the light intensity up to 1,600 PPFD, but it was decreased at 2,000 PPFD. The highest photosynthetic rate was shown in L. fischeri var. spiciformis, followed by L. fischeri, and L. stenocephala. was the highest $27.39{\mu}mol\;CO_{2}m^{-2}s^{-1}$ among three species, followed by that of The differences in photosynthetic rates were significantly different among the species each measuring date. L. fischeri var. spiciformis was more adaptive species at the low elevated under-tree cultivated sites, such as, Sanchemaeul Dunnae-myeon Hoeyngseung-gun than L. fischeri and L. stenocephala.

• Journal of Environmental Science International
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• v.16 no.11
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• pp.1313-1318
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• 2007

Illicium anisatum was bred under four different light intensity. Those condition were full sunlight(PPFD $1600{\mu} mol\;m^{-2}s^{-1}$), 30% treatment(PPFD $400{\mu} mol\;m^{-2}s^{-1}$), 50% treatment(PPFD $250{\mu} mol\;m^{-2}s^{-1}$) and 70% treatment(PPFD $100{\mu} mol\;m^{-2}s^{-1}$), respectively. Chlorophyll a and b were increased according to decrease of light intensity. Thirty percent and 50% treatment had not significant different in chlorophyll a and b. Thirty percent treatment was shown the best photosynthetic activity through invested photosynthetic rate, intercellular $CO_2$ concentration and water use efficiency. Photosynthetic activity trend of 50% treatment was similar to 30% treatment. Seventy percent treatment was shown the best photosynthetic activity at low light intensity but that was decreased to lower value than 30% and 50% treatment under high intensity. Control, bred full sunlight, was shown the worst photosynthetic activity at measured all light intensity. That result could imply that was caused by photo-inhibition because of long term exposed of shade tolerant plant at high light intensity. Leaf characteristics had not significant different in leaf length, width and area but leaf dry weight had similar trend to photosynthetic activity.

• Journal of Korean Society of Forest Science
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• v.100 no.4
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• pp.733-737
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• 2011

We investigated the effect of artificial warming on chlorophyll contents and net photosynthetic rates of 2-year-old Quercus variabilis seedlings in a nursery open-field experiment site. 64 seedlings were each planted in $1m{\times}1m$ plots (n = 4) and warmed with infrared lamps. The air temperature in warmed plots was $3^{\circ}C$ higher than that of control plots. Chlorophyll contents and net photosynthetic rates were measured in May, July, August, September and October, 2011. In May, September and October chlorophyll contents and net photosynthetic rates were significantly higher in warmed plots than in control plots. However, there were no significant differences in chlorophyll contents and net photosynthetic rates between warmed plots and control plots in July and August. It seemed that early developed leaves of warmed plots in May with higher chlorophyll contents could lead to higher net photosynthetic rates whereas there was no difference in net photosynthetic rates due to saturation of chlorophyll contents in July and August. Increased biosynthesis of chlorophyll due to warming might increase net photosynthetic rates in September and October.

• Journal of Environmental Science International
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• v.15 no.12
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• pp.1109-1117
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• 2006

To investigate the influence of the mesophyll cells on stomatal opening in response to white light, the segments of isolated epidermis were transferred on partly exposed mesophyll cells of a leaf and stomatal apertures were measured. Transferring the isolated epidermis on partly exposed mesophyll cells of a leaf caused a marked increase on stomatal apertures while stomata in isolated epidermis incubated in MES buffer hardly opened. Mesophyll infiltration with photosynthetic inhibitors (DCMU, DCCD, $NaN_3$) was performed to elucidate the correlation between stomatal apertures and the degree of photosynthetic activity. It was found that transferring the isolated epidermis on partly exposed mesophyll cells of a leaf caused an increase of stomatal apertures depending on the degree of photosynthetic activities. In $NaN_3$ infiltrated leaf discs, transferring the fresh isolated epidermis on partly exposed mesophyll cells of a leaf showed no significant effect, but a slight increase on stomatal apertures. Isolated epidermis alone did not respond to the light properly, but if it was closely contacted with mesophyil cells, the stomata regained the ability of the light response. Therefore, it could be suggested that stomatai apertures were related with the degree of photosynthetic activity in the mesophyll cells.

• 한국생물공학회:학술대회논문집
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• 2000.04a
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• pp.189-192
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• 2000

The objective of this study was to investigate the effect of high content of light-absorbing pigments on overall photosynthetic efficiency in high density microalgal cultures. The light harvesting complex II (LHC II) regulating gene of Rhodobacter sphaeroides, photosynthetic purple bacterium, was removed to construct a mutant strain that had less pigment content. The mutant and wild type strains were cultured under various light intensity by adjusting the distance from the light source. The productivity of the mutant strain was higher at high light intensity (over 118 ${\mu}E/m^2/s$) compared with one of the wild type , and was lower at low light intensity (34 ${\mu}E/m^2/s$). Especially, the concentration of LHC II mutant strain was 56% higher at 118 ${\mu}E/m^2/s$. The reduction of per cell pigment contents in the mutant strain lessened the degree of the mutual shading and thus enhanced the overall photosynthetic efficiency.

• Applied Biological Chemistry
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• v.24 no.2
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• pp.132-138
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• 1981

Four species of the photosynthetic bacteria from 36 samples were isolated. their characteristics, their capability for nitrogen fixation and their capability for purification of organic waste water by photosynthetic bacteria were examined. Photosynthetic bacteria are widely distributed in soil. The isolated species are Rhodopseudomonas capsulatus. R. spheroides, R. gelatinosa, and R. ruburm. The capability for nitrogen fixation varies with the species of photosynthetic bacteria, and it is very pronounced in the R. capsulatus. The capability for purification of organic waste water is relatively strong but varies with the species.

• Asian Journal of Turfgrass Science
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• v.11 no.1
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• pp.59-72
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• 1997

The influence of respiration on photosythetic electron transport were investigated in the Wid type and psaB mutants from Syneehocystis sp. PCC6803. The amount of glucose uptake in the wild type was proportional to the glucose concentration added in wild type and less than that of psaB mutants in the dark. It was suggested that psaB mutants more depend on the glucose than the wild type. It was investigated how the activities of isocitrate dehydrogenase(IDH) and glucose-6-phos-phate dehydrogenase(G6PDH) were changed. The activities of IDH were very low. While, the ac-tivities of G6PDH were much higher than that of IDH. These results agree to the reports that ex-ogenous glucose was dismilated aerobically via Oxidative Pentose Phosphate Pathway in heterotrophic cyanobacteria. PsaB mutants showed high G6PDH activity in the presence of glucose as well as in the dark and high respiratory activities especially in the dark. It was also investigated how photosynthetic electron transport activities were changed. PsaB mutants showed higher photosynthetic electron tranasport activities than wild type in the presence of glucose as well as in the dark. In the results, it was proposed that photosynthetic electron transport between PS I and PS U was complemented by respiratory electron transport through the NADPH generated by Dxidative Pentose Phophate Pathway in psaB mutant from Synechocystis sp. PCC6803. Key words: Photosynthetic electron transport, Respiration, Synechoystis sp. PCC6803, psaB mutant, Glucose uptake, IDH, G6PDH, Respiratory electron transport activity.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.33 no.4
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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;.

• Journal of Korean Society of Forest Science
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• v.95 no.5
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• pp.562-568
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• 2006

This study was conducted to examine the energy content and photosynthetic efficiency of Quercus mongolica stands in Korea. Study sites were located in Mt. Joongwang, Gangwon-do (1,000 m and 800 m above sea level), Mt. Baekwoon, Jeollanam-do (800 m a.s.l.), Mt. Halla, Jeju-do (1,000 m a.s.l.), Mt. Taehwa, Gyeonggi-do (350 m a.s.l.), and Mt. Wolak, Chungcheongbuk-do (300 m a.s.l.). Total energy content and annual energy accumulation in Q. mongolica stands were 2,916-6,435 GJ/ha and 284-441 GJ/ha, respectively. Lower latitude (N.L.) stands of Q. mongolica showed higher energy contents than higher latitude stands, but Quercus stands in Mt. Baekwoon had higher annual energy accumulation than those in Mt. Halla located at a lower latitude. During the growing season, the photosynthetic efficiency of 60 to 70-year-old Q. mongolica stands ranged from 1.19 to 1.34% while that of 35-year-old stands did from 1.87 to 1.95%. There were no significant differences in photosynthetic efficiency among the latitudes because solar radiation was higher in low latitudes.