• Horticultural Science & Technology
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• v.19 no.4
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• pp.501-504
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• 2001

The effect of soil EC on tissue morphology of leaf and shoot tip in cucumber (Cucumis sativus L. cv. Euinchim-baekdadagi) seedlings was investigated. Number of trichomes on leaf upper epidermis increased with the increase in soil EC from 1.0 to $3.0dS{\cdot}m^{-1}$, but the shape and number of stomata on lower epidermis remained unchanged. Epidermal cells of cucumbers grown in EC $1.5dS{\cdot}m^{-1}$ soil was occupied mostly by large vacuole whereas those grown in EC $3.0dS{\cdot}m^{-1}$ soil were filled with a nucleus, mitochondria, chloroplast and other micro-organelles. Sponge parenchima cells were also larger and contained fewer chloroplasts at EC $1.5dS{\cdot}m^{-1}$ than those grown at EC $3.0dS{\cdot}m^{-1}$. Leaf thickness decreased at high EC and the color of epidermal cells became significantly darker on the photograph of optical microscope. Normal tissue differentiation was greatly suppressed in plants grown in soils with $3.5dS{\cdot}m^{-1}$ or higher EC.

• Korean Journal of Plant Taxonomy
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• v.33 no.4
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• pp.435-454
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• 2003

The morphology of plants and scanning electro-microscopical features of fruits were examined to evaluate the taxonomic entities of Korean Adonis L. in sensu lato (Ranunculaceae). The species of Korean Adonis were readily diagnosed by the branching pattern of stem, the number of flowers, the bifurcation of leaf main axis, the number of tepals, the flowering periods in relation to leaf sprouting, and the number of stomata and the texture of fruit surface. This study demonstrates that there are three species, A. amurensis, A. pseudoamurensis, and A. multiflora., found in Korea. However, A. ramosa, which has been often claimed to be distributed in Korea, is not present in Korea.

• The Korean Journal of Ecology
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• v.14 no.4
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• pp.371-377
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• 1991

Some morphological characteristics were investigated on the leaves of quercus aliena, hypostomatous species, and lespedeza cyrtobotrya, amphistomatous species, that appeared dominantly on the rock faces in mt.pukhan, mt surak and mt. pulam near seoul. These characteristics were compared with those of normal sites rock faces. All two species growing on the rock faces had thickened leaves with well developed upper epidermis and palisade tissue. Quercus aliena growing on the rock faces showed the leaves with double layer of palisade cells and more regularly arranged spongy parenchyma cells to the lower epidermis. In the case of lespedeza cyrtobotrya, narrower and more lengthened palisade cells and smaller air gaps between the sponge parenchyma cells were observed on the rock faces than those growing in the normal sites. The stomater frequency of the lower epidermis of the tree leaves growing on the rock faces is higher thanthose of normal sites. However, the mean total stomata number of the tree leaves growing on the rock faces are fewer. Most of the morphological characteristics investigated indicate that the plants on the rock faces havesmaller coefficient of variation than those of the normal sites.

• Journal of People, Plants, and Environment
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• v.23 no.1
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• pp.15-21
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• 2020

In this study, we compared efficiency of different aquatic plants in removing indoor pollutants and examined their potential to purify indoor air. Two liter of water in chamber was used as the control, while the other chambers containing water lettuce (Pistia stratiotes), water hyacinth (Eichhornia crassipes), and water coin (Hydrocotyle umbellata) were used as treatment groups. Temperatures inside all the chambers were maintained between 20 ℃ and 23 ℃. Humidity in the chambers with aquatic plants increased by 30% and 50% control respectively. The removal of formaldehyde per unit leaf area was examined in each aquatic plant. It turned out that water hyacinth removed the highest amount of formaldehyde, followed by water lettuce and water coin. Both water hyacinth and water lettuce increased the amount of removal of formaldehyde until the end of the experiment. In the case of airborne dust (PM 10) and fine dust (PM 2.5), water coin, which had the highest number of leaves, removed more PM 10 and PM 2.5 than the other aquatic plants, with statistically significant difference. In addition, both water coin and water hyacinth smoothly opened and closed stomata before and after the experiment. Consequently, as the aquatic plants were effective in controlling humidity and removing pollutants, they can be used as air purifying plants.

• Journal of Plant Biotechnology
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• v.33 no.2
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• pp.117-122
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• 2006

Comparative studies on medium supply in bioreactors (raft, immersion and ebb and flood) have revealed that multiplication and growth of Alocasia Amazonica were greatest in the raft system, while lowest in ebb and flood system. In the raft system, the basal part of the shoots was continuously in contact with medium, which enabled a constant uptake of nutrients as well as aeration to the explants. The number and the size of leaf stomata were higher in the raft system compared with immersion and ebb&flood system. In the immersion system, plantlets were deformed and epidermal cells in leaves were irregular with a large intercellular space. The results suggested that the medium supply should be controlled properly to maintain normal and healthy plantlets during liquid cultures in bioreactors Which affects morphology and physiology Of the plantlets.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.27 no.2
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• pp.175-181
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• 1982

This experiment was carried out to study the influence of the various soil water regimes on photosynthesis and growth and development of ginseng plant (3 years). The results were as follows: optimum soil water content for root dry weight and diameter appeared to be 62% of field capacity (13.9% fresh weight basis). The 62% field capacity showed superiority in leaf area, leaf dry weight and also in number of flower, fruit, seed per plant. Net photosynthesis rates per unit area increased with increasing soil water content but net photosynthesis rates per plant were superior in 62% field capacity. Rates of transpiration increased linearly with increasing soil water content but density of stomata decreased with increasing soil water content.

• Molecules and Cells
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• v.41 no.5
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• pp.413-422
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• 2018

Soybean transgenic plants with ectopically expressed AtABF3 were produced by Agrobacterium-mediated transformation and investigated the effects of AtABF3 expression on drought and salt tolerance. Stable Agrobacterium-mediated soybean transformation was carried based on the half-seed method (Paz et al. 2006). The integration of the transgene was confirmed from the genomic DNA of transformed soybean plants using PCR and the copy number of transgene was determined by Southern blotting using leaf samples from $T_2$ seedlings. In addition to genomic integration, the expression of the transgenes was analyzed by RT-PCR and most of the transgenic lines expressed the transgenes introduced. The chosen two transgenic lines (line #2 and #9) for further experiment showed the substantial drought stress tolerance by surviving even at the end of the 20-day of drought treatment. And the positive relationship between the levels of AtABF3 gene expression and drought-tolerance was confirmed by qRT-PCR and drought tolerance test. The stronger drought tolerance of transgenic lines seemed to be resulted from physiological changes. Transgenic lines #2 and #9 showed ion leakage at a significantly lower level (P < 0.01) than ${\underline{n}}on-{\underline{t}}ransgenic$ (NT) control. In addition, the chlorophyll contents of the leaves of transgenic lines were significantly higher (P < 0.01). The results indicated that their enhanced drought tolerance was due to the prevention of cell membrane damage and maintenance of chlorophyll content. Water loss by transpiration also slowly proceeded in transgenic plants. In microscopic observation, higher stomata closure was confirmed in transgenic lines. Especially, line #9 had 56% of completely closed stomata whereas only 16% were completely open. In subsequent salt tolerance test, the apparently enhanced salt tolerance of transgenic lines was measured in ion leakage rate and chlorophyll contents. Finally, the agronomic characteristics of ectopically expressed AtABF3 transgenic plants ($T_2$) compared to NT plants under regular watering (every 4 days) or low rate of watering condition (every 10 days) was investigated. When watered regularly, the plant height of drought-tolerant line (#9) was shorter than NT plants. However, under the drought condition, total seed weight of line #9 was significantly higher than in NT plants (P < 0.01). Moreover, the pods of NT plants showed severe withering, and most of the pods failed to set normal seeds. All the evidences in the study clearly suggested that overexpression of the AtABF3 gene conferred drought and salt tolerance in major crop soybean, especially under the growth condition of low watering.

• The Korean Journal of Ecology
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• v.4 no.3_4
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• pp.114-123
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• 1981

Diurnal acid fluctuations, stomatal resistance, and morphology and anatomy were investigated in leaves and stems P. oleracea L. growing under the natural environmental condition. A CAM-like pattern of acid fluctuation was exhibited not in leaves of the young purslane but in its stems. Defoliated stems showed a decreased in diurnal changes of total acidity as compared with normal stems. Excised stems stored in continuous darkness exhibited diurnal acid rhythms, and they showed light deacidifications for three days. Kranz-type arrangement was observed in leaves, but not in stems. Micrography of cross sections of stems showed cells with relatively large vaculoles and a few chloroplasts. The number of stomata was 3,275cm-2 in leaves, while the stomata could not be observed in stems. Stomatal resistance was high at night and low in daytime in leaves of the young purslane, and the range of its value was 5~40 sec.$\textrm{cm}^{-1}$. But stomatal resistance in leaves of the water-stressed plant was comparratively high in day time, and its value was 30 sec.$\textrm{cm}^{-1}$. The result of these studies showed the possibility that the stem of P.oleracea L. possesses CAM under certain stressed conditions.

• Journal of Plant Biology
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• v.29 no.1
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• pp.41-51
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• 1986

The plants of Nicotiana tabacum L. cv. NC2326 were germinated in 10 cm D$\times$20 cm H polyethylene pot, and sand-cultured with Hoagland solution near by the window of laboratory room(26$\pm$5$^{\circ}C$). The growing plants were sprayed with various concentrations of ABA around 9 : 00 a.m. once in every two days for 12 weeks in summer. As the results, frequency of stomatal number, stomatal opening, chlorophyll content, respiration rate, and protein content in the leaves were decreased with the increasing of concentrations of ABA, respectively. The plant growth was inhibited by exogenous ABA, but leaf abscission was not found during the experimental period. The ratio of three to one in chlorophyll a to b was not altered by exogenous ABA. All the stomata were closed within three minutes by 100 $\mu\textrm{g}$ ml-1 ABA and within seven minutes by 1-10 $\mu\textrm{g}$ ml-1 ABA after the spraying of ABA, and then reopended after a few hours in 1-10 $\mu\textrm{g}$ ml-1 ABA and after 24 hours in 100 $\mu\textrm{g}$ ml-1 ABA. The polar movement of chloroplast within the guard cells was found in the higher concentrations of 10 and 100 $\mu\textrm{g}$ ml-1 ABA, but not found in the lower concentrations than 1 $\mu\textrm{g}$ ml-1 ABA. During the night and weak light, it was fond that the inhibition of respiration rate by the higher concentration of ABA was owing to firstly the stomatal closure by the spraying of ABA and secondly the decrease of stomatal frequency by the inhibition of stomatal development with exogenous ABA for the long period of 12 weeks. In the band number of leaf protein by the electrophoresis, most of the protein bands were disappeared by the higher concentration of 100 $\mu\textrm{g}$ ml-1 ABA, but were not altered by the lower concentration of ABA in comparison with control.

• Journal of Korean Society of Forest Science
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• v.87 no.1
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• pp.50-56
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• 1998

Thirty-six $F_3$ hybrid poplar (Populus trichocarpa${\times}$P. deltoides) clones were fumigated with ozone to select for ozone sensitive and resistant clones. Fumigation was applied for 6 to 8 hours each day for approximately 3 months at ozone concentrations of 90 to 115 ppb using by open-top chambers. Height, diameter, number of leaves, total biomass, biomass components, root/shoot ratios, leaf drop and stomatal response were investigated. In summary, ozone generally reduced height, diameter, number of leaves, total biomass, and root/shoot ratios. Ozone stress induced leaf drop and foliar senescence in trees. This study showed very low relationship between total biomass and stomatal conductance. Increased plant resistant to ozone is not always correlated with stomatal behaviour. Probably, characterization of biochemical and other physiological responses to ozone exposure can provide a better understanding of tree response to ozone environment.