• KOREAN JOURNAL OF CROP SCIENCE
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• v.39 no.4
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• pp.307-316
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• 1994

To investigate the effect of light pretreatment on photosynthetic characteristics of leaf blade of rice, 2 varieties of japonica type and 2 varieties of tongil type were grown under 30% or 70% shading conditions from tillering stage to heading stage. Shading treatment of 70% at the heading stage produced low dry matter, and higher LAR and SLA compared with other combination of shading treatment and growing stage did. Photosynthetic activity was lower in order of 0%, 30% and 70% shading treatment under the low light intensity(5Klux) but significantly high in 30% shading treatment under the high light intensity (33Klux) at tillering stage. Photosynthetic activity under low(5Klux) and high(33Kluk) light intensity were higher in order of 70%, 30% and 0% shading treatment at heading stage. Respiration /photosynthesis ratio was lower in shading treatment than in control. CGR, RGR and NAR decreased in shading treatment. Shading treatment reduced the number of ripened grain per panicle and decreased the harvesting index.

• Journal of agriculture & life science
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• v.46 no.4
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• pp.93-99
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• 2012

This study was conducted to investigate photosynthetic characteristics of two-year-old of Adenophora triphylla var. japonicum grown under control (full sunlight) and three different shading treatment (25, 50, and 75% shading treatment). Total chlorophyll contents like chlorophyll a and b content had not significant difference among treatments. Net photosynthetic rate of control and 25% treatment were higher than 50% and 75% treatment. Seedlings grown under full sunlight showed the highest photosynthetic activity such as photosynthetic rate, stomatal conductance and intercellular $CO_2$ concentration except for water use efficiency which was relative higher under 50% and 75% treatment.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.33 no.4
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• pp.353-359
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• 1988

Variations in photosynthetic capacities of leaves differing in thickness were explained on the basis of relationships between gas exchange and internal leaf structure. The relative importance of gas diffusion and of biochemical processes as limiting for leaf photosynthesis was also determined. Mesophyll cell surface was considered to be the limiting internal site for gas diffusion. and cell volume to be indicative of the sink capacity for CO$_2$ fixation. Increases in cell surface area were assumed to reduce proportionately mesophyll resistance to the liquid phase diffusion of CO$_2$. Increased cell volume was thought to account for a proportional increase in reaction rates for carboxylation, oxygenation. and dark respiration. This assumption was tested using chamber-grown Glycine max (L.) Merr. cv. Amsoy plants. Plants were grown under 200, 400, and 600 ${\mu}$mol photons m$\^$-2/ s$\^$-1/ of PAR to induce development of various leaf thickness. Photosynthetic CO$_2$ uptake rates were measured on the 3rd and 4th trifoliolate leaves under 1000 ${\mu}$mol photons m$\^$-2/ s$\^$-1/ of PAR and at the air temperature of 28 C. A pseudo -mechanistic photosynthesis model was modified to accommodate the concept of cell surface area as well as both cell volume and surface area. Both versions were used to simulate leaf photosynthesis. Computations based on volume and surface area showed slightly better agreement with experimental data than did those based on the surface area only. This implies that any single factor, whether it is photosynthetic model utilized in this study was suitable for relating leaf thickness to leaf productivity.

• 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.

• Journal of Korean Society of Forest Science
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• v.98 no.1
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• pp.106-114
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• 2009

This present study was conducted to investigate photosynthetic characteristics, chlorophyll fluorescence, chlorophyll contents of Allium victorialis var. platyphyllum, Ligularia fischeri, Ligularia stenocephala growing under four different light intensity regimes (full sun, and 64~73%, 35~42%, 9~16% of full sun). Three wild vegetables showed good photosynthetic capacity in July. Allium victorialis var. platyphyllum showed best photosynthetic capacity and apparent quantum yield in 35~42% of full sun. But Ligularia fischeri and Ligularia stenocephala showed best photosynthetic capacity and apparent quantum yield in full sun and decreased as the shading level increaese. As the shading level increased, the total chlorophyll contents increased with a significant difference in three wild vegetables.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.30 no.4
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• pp.347-351
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• 1985

The effect of leaf water content on apparent photosynthesis and respiration of tobacco plants(five varieties) was studied under the condition without the irrigation for 10 days after the plants were sufficiently watered on the first day. The wild race (N. longiflora) among varieties showed highest apparent photosynthesis (AP) and AP had a positive correlation with specific leaf weight. N. longiflora and Andongyeob were different in their AP from the other varieties significantly under the water stress condition. Respiration rate also decreased to be simillar to AP except slight increase at early stage of water deficit. The stomatal resistance and the mesophyll resistance increased in the stressed plants. The water stress resistant character seems to be mainly due to open stomata.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.30 no.4
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• pp.398-404
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• 1985

This study was conducted to define the seasonal differences in the morphological characteristics, the photosynthetic abilities and the dark respirations of the 4-year old ginseng leaves. Chlorophyll-a content in the ginseng leaf was significantly decreased at September than at June but content of chlorophyll-b was not showed seasonal difference. At June, the amounts of chlorophyll a and b in the ginseng leaves grown in the back row were rather abundant than those grown in the front row, but no significant differencies were detected between rows at September. The estimated optimum light intensity for the photosynthesis of ginseng leaves was higher at June than at September and higher in the front row than the back row but was significantly decreased by air temperature above 25$^{\circ}C$. The light compensation point was elevated in higher temperature and at September than June. The amount of photosynthesis was significantly increased in the ginseng plant grown in the front row than the back row at June but the reverse was significant at September. The highest photosynthesis was observed in temperature range of 20 - 25$^{\circ}C$ at June and range of 15 -20$^{\circ}C$ at September. The optimum temperature range of photosynthesis was 21$^{\circ}C$ to 25$^{\circ}C$ at June and 14$^{\circ}C$ to 21$^{\circ}C$ at September, and that was higher in the back row than the front row. High temperature significantly stimulated the dark respiration of ginseng leaves and the respiratory quotients(Q$\_$10/) of the ginseng leaves showed a significant seasonal variation.

• Journal of Korea Foresty Energy
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• v.23 no.1
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• pp.19-25
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• 2004

This study was performed to investigate the growth and photosynthetic rate of ten-years old Pinus koraiensis and Pinus rigida in Banwol industrial region comparing with those of the control site in Gwangju, Gyeonggi Province. Surface soil of the damaged site in pH 4.2 was more acidic than control site in pH 4.8, assuming the accelerated soil deterioration by acid deposition. The shoot growth, needle survival rate and net photosynthetic rate of P. koraiensis and P. rigida at the damaged site were lower than at the control site. In addition, the quantum yield and chlorophyll a+b and b contents reduced in damaged treatment. These results suggest that an inhibition of photochemical reaction of P. koraiensis and P. rigida at the damaged site of Banwol industrial region could be attributed to combined influence of atmospheric pollution and soil acidification.

• Korean Journal of Medicinal Crop Science
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• v.2 no.1
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• pp.14-19
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• 1994

Elephant food(Amorphophallus konjac K.) have been utilized its tubers in workedmaterials for a health and diet food. The author supposed that it was increased the area of cultivation and demand. This experiments were conducted to select the proper covering material during winter in order to increase yield of tubers and decrease input by 2 year's continuous cultivation, also to verified ability of seed germination and to measured efficiency of photosynthesis of plant. The proper covering materials for wintering were rice straw and rice hull. These materials were covered at 5 cm thick and at field was promoted according to emergence appearing after winter. The yields were 5,790kg /10a at 4,730kg /10a, respectively. Yield increase was 120% and 80% than that of control. The seeds collected at August 22 were germinated about 84 percent, and it was not necessary to treatment of low temperature or germination-accelerated chemicals. The widest leaf area was ranged $1,218-1,438cm^2$ at October 20 and was varied. The efficiency of photosynthesis was highest at 65-95 days after leaf emergence. The line of broad leaf and high photosynthetic efficiency per unit area was greater compare with yield. Therefore, it was supposed that these characteristics will use a marker for selection for high-yielding lines.

• Korean Journal of Medicinal Crop Science
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• v.3 no.2
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• pp.146-150
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• 1995

Weed control in the Korean ginseng(Panax ginseng C.A. Meyer) garden is more difficult than in other crops because the ginseng is a perennial crop and has to be cultivated under the artificial shading. As hand weeding is the only practical means to control weed after crop establishment, a selective herbicide would greatly simplify the control of weed in ginseng garden. In an exploratory experiment, the hervicide Fluazifop-butyl was found to be selectively safe for the Korean ginseng plants. Various rates of Fluazifop-butyl were sprayed on 2-, 3-, and 4-years old ginseng plants as a foliar spray to detect crop injury and to difine their critical concentration. No apparent injury to the ginseng plant was noticable even the doubled application rate of Fluazifop-butyl the based on recommended dosage. Neither abnormal foliar change nor any inhibition in leaf and stem growth was resulted for 2-, 3-, and 4-years old ginseng plants treated with Fluazifop-butyl tripled the recommended usage. The foliar treatments of Fluazifop-butyl did not influence the photosynthesis ability but inhibited the respiration of the ginseng leaf.