• The Korean Journal of Ecology
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• v.26 no.5
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• pp.267-271
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• 2003

To elucidate effects of air pollutants on ecophysiological properties of two Quercus mongolica stands at different levels of air pollution, photosynthetic capacity and chloroplast pigment were measured in leaves of Q. mongolica. Photosynthetic capacity, photosynthetic pigment content and SLA (specific leaf area) of Q. mongolica leaves in polluted area were lower than those in nonpolluted area. Also, the chlorosis and mottling in some of leaves were observed in polluted area after August. Except for total carotenoid (P<0.05) the correlations between photosynthetic capacity and pigment content were not significant. Photosynthetic capacity of Q. mongolica leaves in polluted area was decreased after July.

• Journal of Wetlands Research
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• v.15 no.2
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• pp.171-177
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• 2013

This study was conducted to find the leaf morphological responses of Quercus serrata and Q. aliena which are potential natural vegetation of riverine in Korea under elevated $CO_2$ and increased temperature. Rising $CO_2$ concentration was treated with 1.6 times than control(ambient) and increased temperature with $2.2^{\circ}C$ above the control(ambient) in the glass greenhouse. As a result, leaf width length, leaf lamina weight and leaf area of Q. serrata and Q. aliena was respectively increased, and number of leaves and specific leaf area(SLA) was decreased by elevated $CO_2$ and temperature. Leaf width length, leaf lamina length, leaf lamina weight, number of leaves, leaf area, and specific leaf area of Q. serrata were not statistically significant difference between control and treatment. Leaf width length and leaf weight of Q. aliena was increased, but specific leaf area was decreased. These results indicated that Q. aliena was to be sensitive than Q. serrata in response to global warming situation. According to the principal component analysis(PCA), two oak species were arranged based on factor 1 and 2 in the control and warming treatment. And change on the warming treatment was clearly distinguishable from the Q. aliena than Q. serrata.

• Journal of Plant Biology
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• v.28 no.1
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• pp.1-8
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• 1985

To verify the cause of high productivity in Typha stand, leaf area index(LAI), leaf orientation and inclination, specific leaf area (SLA), and radiation interception profiles were determined in a natural Typha$\times$glauca stand. Throughout the growing season, the leaf inclination has been kept at near-right angle and leaf orientation has been random. These chracteristics were responsible for an uniform spatial arrangement of the leaves within the canopy and could be explained by the SLA value, which increased in their higher strata. The extinction coefficient (K) of the canopy, 0.12 to 0.20, was one of the smallest value out of terrestrial plant communities. At least more than 25% of full radiation penetrated into the lowest stratum of the canopy. High productivity of the Typha would be attributed to efficient penetration of the radiation in virtue of the stiff and straight leaves even though rather small LAI.

• The Korean Journal of Ecology
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• v.17 no.1
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• pp.37-47
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• 1994

A study was conducted to examine the leaf expansion forms and to analyze the leaf growth in early growing season of 1992 in a temperate deciduous forest in central region of Korea. After the winter bud scale fell off, the expansion forms of 11 woody species were divided into 3 groups, spreading fan form, opening form from half folding, and unrolling form from main vein. The ratios of leaf area at the end of growing season to that of leaf expantion time varied among species, and were related closely to expansion forms. The leaves reached to full size between the third ten days of April and the middle ten days of May, except for a few species. Leaf weight, however, increased steadily during the growing season. Specific leaf area (SLA) increased rapidly for 10-20 days after leaf expansion and decreased rapidly for 10 days after reaching maximum values, and thereafter decreased slowly. The SLA values of trees were smaller than $200cm^2/g$, but those of subtree and shrub were larger than $200cm^2/g$.

• Korean Journal of Medicinal Crop Science
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• v.10 no.5
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• pp.409-414
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• 2002

This study was carried out in order to investigate the main traits related to photosynthesis by multiple regression analysis. The photosynthetic rate showed more significant increase in shaded leaves of plant than in non-shaded leaves of plant after shading treatment for 44 days. Negative correlation was found between net photosynthetic rate and SLA(specific leaf area). However, the values obtained from the linear equation were different and were highly significance. From the above results, net photosynthetic rate of shading treatment is higher than that of control in the same SLA. We also found that there were correlation between stomatal conductance and SPAD as well as net photosynthetic rate and stomatal conductance. By the multiple regression analysis, SPAD value, SLA, stomatal conductance and leaf water potential showed a higher correlation coefficient of $r=0.848^{**}$. From the results, out of 4 factors(SPAD value, SLA, stomatal conductance, leaf water potential) stomatal conductance was main factor in the view points of partial regressing.

• Journal of Life Science
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• v.8 no.5
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• pp.492-496
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• 1998

Intact measurement of leaf water content was attempted using the transmission of beta radiation. Prior to the experiments, two tested plants, rice and soybean, were grown in 1/5000a wagner pot. The moisure ratio of plant leaves were measured with the beta radiation transmission method using a G-M detector and $^{99}$ Tc as the beta ray sou-rce. Beta radiation transmission showed a tendancy to increase with the passage of time after leaf cutting. However, it showed a tendancy to decrease with water supply for the lack of water. A positive correlation was found between the leaf water content and beta radiation transmission. The mutiple regression analysis about leaf water content was obtained that the coefficient of partial regression for beta radiation transmission was much higher(rice; -0.863, soybean; -0.904) than that for specific leaf area(rice; 0.007, soybean: 0.004).

• Horticultural Science & Technology
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• v.31 no.4
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• pp.415-422
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• 2013

This study was conducted to establish the optimum LED light source and quality for growth of Wasabia japonica seedlings in the LED chamber plant factory system. The light treatments were combined with four colors LED (red, blue, white, far-red), irradiation time ratio of the red and blue LED per minute(1:1, 2:1, 5:1, 10:1), and duty ratio of mixed light (100%, 99%, 97%). The growth response of W. japonica was the greatest in the R + B mixed light treatment, and seedlings grown in the red LED alone was higher than blue LED alone in the monochromic radiation treatments. In the R + B mixed LED, 1:1 ratio of R and B was the best for total biomass and tiller production. In mixed light treatments, the growth response of W. japonica was highest in the 100% duty ratio with R + B mixed light, while that was highest in the 97% duty ratio with R + B + W mixed light. Leaf area and dry weight were increased in the red light treatment alone, while specific leaf area was increased in the blue light alone. With the increasing red LED light ratio, leaf area and dry weight of W. japonica was significantly increased under the R + B mixed light treatment. In mixed light treatments, the leaf growth responses of W. japonica was highest in the 97% duty ratio with R+B mixed light, while that was highest in the 100% duty ratio with R + B + W mixed light. For cultivating W. japonica in a plant factory, treating red LED supplemented with a blue light or higher ratio of the red to blue LED was benefit to promote the growth of W. japonica.

• Journal of Plant Biology
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• v.38 no.1
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• pp.63-72
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• 1995

The growth, size and morphology of leaves, which foliated on the same shoot and time in the early growth season, were studied in 12 woody species in temperate deciduous forests of Korea, and the equation for the index of heteromorphism of leaves was fonnulated. The numbers of leaves per shoot were from 3 to 7 in early growth season and the numbers of synchronous leafing were from 2 to 6. All the leaves on a shoot were reached maximum values of specific leaf arells at the SIlme time nearly. The differences of the length (L) and breadth (B) of leaves along leaf rank (plastochron) were conspicuous, except for Quercus variabilis. Especially, in 10 species, the ~fferences of the neighbouring leaves were significant at 0.001 or 0.05 level. The index of leaf heteromorphism was calculated from the data based on $L\;{\times}\;B$ and LIB, and similar to differences of actual leaves along leaf rank. The values of index of heteromorphism were high in Carpinus tschonosldi, Styrax obassia, Ulmus davidiana, Rhamnus yoshinoi and Symplocos chinensis for. pilosa, and low in Sorbus alnifolia and Tilia amurensis. The index of heteromorphism had no relation to other characters of the leaf or life fonn of the species. It was thought that the differences along leaf rank were related to the degree of adaptation to environment, especially to changing air temperature in early growth season.season.

• Journal of Bio-Environment Control
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• v.3 no.2
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• pp.119-127
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• 1994

This study was conducted to investigate the effects of temperature and light conditions on the vigor and growth responses of red pepper(Capsicum annuum L.) seedlings in the nonheated plastic houses with triple and quadruple coverings during winter. The results obtained were as follows ; 1. The growth in terms of plant height, number of leaves, leaf area and dry weight of each organ was reduced up to 50% in the triple coverings compared to quadruple ones. The greatest difference between the triple coverings and quadruple ones was the leaf area, showing two to five times larger in the quadruple ones. Therefore, the differences of the early environmental conditions during raising seedling stage was well reflected. 2. The leaf expansion in the early stage of seedling was delayed in the triple coverings and subsequently crop growth rate(CGR) significantly reduced. The specific leaf area (SLA) in the triple coverings was less than quadruple ones. The net assimilation rate (NAR) was increased in the early stage of seedlings and then reduced in the quadruple coverings. In triple ones, however, the great reduction showed at six weeks after sowing and then increased sharply. 3. The linear relationship among leaf area, total dry weight and leaf dry weight was observed in the all experimental areas, while between leaf area and crop growth rate only in the quadruple coverings, and between leaf area and net assimilation rate in both triple and quadruple ones. 4. The dry matter partitioned to the leaf increased up to six weeks after sowing in the triple coverings but reduced in the stem and root. However, the adverse results were obtained in the quadruple ones. 5. In the triple coverings, the number of branches showed the exponential increment while fruit weight showed linear increment in both triple and quadruple ones. Higher yield was obtained in the quadruple ones. 6. The shoot dry weight among the characteristics of seedlings was greatly contributed to the yield of red pepper after transplanting. Accordingly, one of the decisive criterion for good quality of red pepper seedlings was determined by the highest correlation between shoot dry weight of growing plant and fruit yield of pepper plant.

• Korean Journal of Medicinal Crop Science
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• v.15 no.3
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• pp.152-156
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• 2007

The Condonopsis lanceolata Trautv. was planted in field to investigate the effect of afterwards shading in the condition of sun light of fifty six percent on the characteristics of photosynthesis according to leaf position at flowering stage. The vine length and leaf area were increased with shading treatment in comparison with that of non-shading. Dry weight of leaf and vine indicate opposite tendency with the result above. SLA (specific leaf area) was much more increased in shaded leaves than that obtained from non-shading treatment. The shaded leaves of plant show a higher SPAD value than that of non-shaded leaves. The net photosynthetic rate and stomatal conductance were increased as the PAR was increased. And it is the maximum valve (PAR of 700-1000 ${\mu}$mol/m$^2$/s of PAR) of all leaves. Overnurse and light saturation point of the Condonopsis lanceolata Trautv. shading-treated was improved in comparison with control as net photosynthetic rates of leaves positioned on each part of the stem was increased.