• Korean Journal of Environment and Ecology
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• v.19 no.4
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• pp.348-357
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• 2005

The present study was carried out to analyze the leaf variation of hex corn uta which are one of very important native landscape woody materials, but rapidly destroyed by habitat alteration in the past decades. The leaf characters were ranged as 0.9-11.8cm for the leaf length, 0.4-7.7cm for the leaf width, 0.2-13.0mm for the petiole length, $0.7-46.7cm^2$ for the leaf area and 1-13 for the number of leaf serrations. Due to the leaf shape, number of spines, and colours of leaf and fruits, which are the main characters of the cultivars of the Chinese holly, the hollies in the wild and planted as identified as 9 cultivars and one hybrid including 'Cholbuam', 'Inchon' and 'Sun Chun'.

• Korean Journal Plant Pathology
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• v.11 no.3
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• pp.282-284
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• 1995

Grey leaf spot on tomato plants was first observed in Sedo-myeon, Puyo-kun, Chungnam province of Korea in 1994. This disease which had not been reported before in Korea exhibited different symptoms from those of other leaf spot diseases on tomato plants. The symptoms were characterized by small irregular-shaped spots on leaves at the initial stage of the infection, subsequent spread and coalescence of the spots throughout the leaves with ultimate necrosis, and abscission from the plants. When healthy tomato plants were inoculated with a conidial suspension of the fungus isolated from the lesion of a diseased plant in a field, the same characteristic symptoms as those in the field were produced. Furthermore, the same pathogen could be reisolated from the lesions formed buy the inoculation. Conidial characteristics of the pathogen were as follows; oblong shape with constricted 3 transverse septa, round-shaped base, round- or point-shaped apex, size of 45~75$\times$12.5~17.5 ${\mu}{\textrm}{m}$, and 3.5 : 1 ratio of length to width. The pathogen was identified as Stemphylium lycopersici and thus this is the first report on the occurrence of grey leaf spot disease on tomato plants caused by s. lycopersici in Korea.

• Journal of radiological science and technology
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• v.22 no.1
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• pp.61-66
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• 1999

The use of multileaf collimator(MLC) to replace conventional field-shaping techniques is not in itself expected to improve the local control of malignancy. The purpose for using MLCs in conventional radiation oncology is to improve the efficiency of treatment delivery. For effective clinical application of MLCs to shaped radiation field, field outline must be translated into MLC leaf position tables. The intended leaf positions contained in these tables must then be communicated to the control computer that drives the MLC. There are currently at least three techniques utilized by manufacturers of MLCs and treatment planning systems for doing this. The Varian series use a workstation employing a manual digitizer and light box especially. It has a third level MLC configuration and also has the option of placing the wedges above or below the block tray. The C language are used for development of software and three leaf coverage have been used for positioning MLC loaves at the nominal field boundary. The fit of the leaf shape to treatment target volumes are optimized by the rotation of the direction in leaf travel. The clinical application of this software are investigated for Varian MLCs used in linear accelerator of Yonsei Cancer Center. The advantage of the results with using this software is to prescribe and calculate exposed and blocked area in MLCs field.

• Korean Journal of Plant Taxonomy
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• v.41 no.3
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• pp.223-229
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• 2011

The taxonomy of the Isodon excisus complex has been ambiguous and problematic because the morphological characters, especially characters related to the leaf distinguishing subgroups of the complex in the original descriptions, are variable. To elucidate the taxonomic structure of the I. excisus complex in Korea, 34 characters were measured from 70 OTUs representing different locations and analyzed by principal component analysis (PCA). The analysis showed that principle component axis 1, 2, 3 (PC1, PC2, PC3) represents 52.0% of the total variance and characters showing high loading values for PC1 were leaf shape, density of non-glandular hairs on the lower surface of the leaf, and characters related to the teeth of the leaf. The length of apical tooth and the angle between two widest points of the leaf were highly correlated to PC2 and PC3, respectively. Three-dimensional scatter plotting of OTUs for PC1, PC2, and PC3 axis showed that the areas of previously recognized three subgroups of I. excisus completely overlapped. Our result supported that just one taxon, I. excisus var. excisus, should be recognized in the complex at the variety level.

• Korean Journal of Plant Resources
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• v.14 no.3
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• pp.188-195
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• 2001

The anatomical characteristics of rhizome, lateral root, stem, leaf, petiole, ovary and leaf epidermis about Atractylodes japonica Koidz. ex Kitam. and A. macrocephala Koidz. were investigated to estimate these taxonomic values. The cross sections of stem and ovary were very similar to two species, therefore these characters were not useful for delimitation of two species, but the size and distribution numbers per 100${\mu}{\textrm}{m}$$^2$of oil cavites in rhizome, the shape of leaf and petiole in cross section, the size of leaf epidermal cell and distribution numbers per 100 ${\mu}{\textrm}{m}$$^2$of stomata were differ from two species, therefore these were thought to be useful characters for delimitation of two species.

• Korean Journal of Environment and Ecology
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• v.28 no.1
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• pp.55-61
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• 2014

To examine the forest structure and variation of samara and leaf shape of Acer pictum subsp. mono (APSM), We investigated forest structure and samara angles and length, and leaf shape in three natural population of APSM in Yanggu-gun, Youngyang-gun and Kwangyang-si from June 2012 to October 2013. Mean importance percentage (MIP) of APSM is shown lower values in Yanggu 19.8%, in Youngyang 22.0%, and in Kwangyang 17.1%, respectively. In middle layer, importance percentage (IP) of APSM is shown lower values than that of Acer pseudosieboldianum and Carpinus cordata. In lower layer, importance percentage (IP) of APSM is shown lower values in Yanggu 1.8%, in Youngyang 1.9%, and in Kwangyang 0.0%, respectively. From these results, MIP of APSM in natural population might be reduced in future. Angles between wings and samara length are significantly different between districts. APSM with seven palmate vein leaf are distributed more frequently at Kwangyang and Youngyang than Yanggu. Percentages of biserrate leaf is shown in Yanggu 0.6%, in Youngyang 15.8%, and in Kwangyang 20.4%, respectively. These results implies genetic variation in natural APSM population and further studies on the genetic variation analysis in natuel population of APSM should be needed.

• Journal of Life Science
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• v.15 no.3 s.70
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• pp.499-504
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• 2005

This experiment was conducted to identify the effect of several plant growth retardants on growth of Sedirea japonica seedlings cultured in vitro and their changes of invertase activities. When seedlings of Sedirea japonica were treated with ancymidol and paclobutrazol, as the concentrations were increased, leaf length was gradually shortened and leaf width became wider than that of control. On the other hand, root length was shorter, but the number of root and the root's diameters were greatly increased, compared with control. In 0.05mg/L uniconazole, growth of leaf and root were enhanced, compared with the control and higher concentrations of uniconazole. As concentration of each growth retardants was increased, leaf shape became round and smaller. Both soluble acid invertase activity and soluble alkaline invertase activity in leaf were decreased in higher concentrations of each growth retardant, but those of the root were contrary to those of the leaf. To confirm the estimated invertase activities, starch content of leaf was higher in low concentration treatments in each growth retardant, but in the root was contrary to content that of the leaf.

• The Plant Pathology Journal
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• v.21 no.1
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• pp.83-85
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• 2005

Ditylenchus acris was isolated from diseased strawberry plants. Frequently, D. acris and Aphelenchoides fragariae occur together in a strawberry plant. Both species appeared very similar in the shape, length, swimming behavior and causing symptoms, and difficult to distinguish them by a stereomicroscope. But they were easily distinguished under a compound microscope especially by their tail shape, median bulb, vulva position, and bursa.

• Journal of Bio-Environment Control
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• v.22 no.4
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• pp.291-297
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• 2013

The objective of this study was to know the growth response and light use efficiency of leaf lettuce (Lactuca sativa L.) 'Yorum Cheongchukmyeon' (green leaf lettuce) and 'Hongyom Jeokchukmyeon' (red leaf lettuce) under different RGB (Red:Green:Blue) ratio in a closed-type plant factory system. The plants were hydroponically cultured with a 12-h photoperiod at $20{\sim}25^{\circ}C$, 60~70% RH and 600~900 ${\mu}mol{\cdot}mol^{-1}$ $CO_2$. The light treatments were combined in three colors LEDs (red, blue, and white) and RGB ratios (1 : 4 : 5, 5 : 0 : 5, 5 : 2 : 3, 7 : 0 : 3, 7 : 1 : 2, and 8 : 1 : 1), however, as the light intensities of treatments were different. Growth characteristic response in both lettuces were significantly as affected by interaction between cultivar and light quality, when they were grown under different light quality conditions. Plant heights of green and red leaf lettuce were the lowest in 1 : 4 : 5 and 8 : 1 : 1, respectively. The highest length and number of leaf were showed 8 : 1 : 1 and 7 : 0 : 3 for the green and 5 : 2 : 3 and 8 : 1 : 1 for the red, respectively. Shoot dry weights of green and red leaf lettuce were the heaviest in 7 : 0 : 3 and 8 : 1 : 1, respectively. Leaf width and leaf shape index were significant about cultivar and light quality. Leaf widths of green and red leaf lettuce were the largest in 8 : 1 : 1 and 5 : 2 : 3, respectively. Leaf shape index of green and red leaf lettuce were the largest in 1 : 4 : 5 and 1 : 4 : 5, respectively. Shoot fresh weight and light use efficiency were significant about cultivar and light quality. Shoot fresh weights of green and red leaf lettuce were the heaviest in 7 : 0 : 3 and 8 : 1 : 1, respectively. Light use efficiencies of green and red leaf lettuce were the highest in 7 : 0 : 3 and 5 : 0 : 5, respectively. These results suggested that the ratio of RGB was 5~7 : 0~2 : 1~3 to cultivate leaf lettuce in a plant factory system.

• Journal of the Korean Society of Tobacco Science
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• v.9 no.1
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• pp.45-55
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• 1987

For some basic information in tobacco breeding, the modes of inheritance and heritabilities for the twelve agronomic and chemical characters were estimated in the study of eight varieties partial diallel set. Additive gene actions were significant for all characters except total nitrogen content and dominance gene effects were also significant for all characters. Yield, number of leaves per plant, leaf length and leaf shape index were inherited as partial dominance, and overdominance was detected for plant height, stem diameter, internode length, total alkaloid, total nitrogen and total sugar content. Dominant gene showed increasing effects in yield, plant height, stem diameter, internode length, leaf width and total sugar content, but showed decreasing effects in the other characters. The broad heritability was very high for all characters. and the narrow heritability was high in days to flower and yield, but low in internode length, total alkaloid, total nitrogen and total sugar content.