• Journal of the Korean Society of Tobacco Science
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• v.14 no.2
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• pp.126-132
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• 1992

This experiment was conducted to examine estimates of heterosis, degree of dominance, heritability and phenotypic and genotypic correlation for several mutant characters in flue-cured tobacco variety. Significant heterosis was noted, recording 2.73 and 6.16% for leaf width, -6.86 and -4.72 for leaf shape index, 19.8 and 23.4% for bacterial wilt disease index in Fl an4 F2 generation, respectively, and -1.44 for days to flower in F2 generation. And also leaf width was appeared partial dominance in Fl, and leaf shape index in Fl and F2, Leaf width in F2 was appeared overdominance. Estimated heritabilities in the broad sense ranged from 0.77 to 0.87 for plant and stalk height and days to flower, while those of leaf number, leaf length and width, leaf shape index and bacterial wilt disease index ranged from 0.50 to 0.65. And the heritabilities in the narrow sense were appeared 0.64 and 0.72 for stalk and plant height, respectively, and the others were ranged from 0.32 to 0.47 Positive genotpic correlations appeared among plant height, stalk height, leaf length and leaf width, and between leaf shape index ands day to flower. And negative genotypic correlations appeared between leaf shape index and plant height and stalk height and leaf width, and between bacterial wilt disease index and leaf length.

• Journal of Plant Biotechnology
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• v.5 no.3
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• pp.137-142
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• 2003

The morphology of the leaves and the flowers of angiosperms exhibit remarkable diversity. One of the factors showing the greatest variability of leaf organs is the leaf index, namely, the ratio of leaf length to leaf width. In some cases, different varieties of a single species or closely related species can be distinguished by differences in leaf index. To some extent, the leaf index reflects the morphological adaptation of leaves to a particular environment. In addition, the growth of leaf organs is dependent on the extent of the expansion of leaf cells and on cell proliferation in the cellular level. The rates of the division and enlargement of leaf cells at each stage contribute to the final shape of the leaf, and play important roles throughout leaf development. Thus, the control of leaf shape is related to the control of the shape of cells and the size of cells within the leaf. The shape of flower also reflects the shape of leaf, since floral organs are thought to be a derivative of leaf organs. No good tools have been available for studies of the mechanisms that underlie such biodiversity. However, we have recently obtained some information about molecular mechanisms of leaf morphogenesis as a result of studies of leaves of the model plant, Arabidopsis thaliana. For example, the ANGUSTIFOLIA (AN) gene, a homolog of animal CtBP genes, controls leaf width. AN appears to regulate the polar elongation of leaf cells via control of the arrangement of cortical microtubules. By contrast, the ROTUNDIFOLIA3 (ROT3) gene controls leaf length via the biosynthesis of steroid(s). We provide here an overview of the biodiversity exhibited by the leaf index of angiosperms. Taken together, we can discuss on the possibility of the control of the shapes and size of plant organs by transgenic approaches with the results from basic researches. For example, transgenic plants that overexpressed a wildtype ROT3 gene had longer leaves than parent plants, without any changes in leaf width. Thus, The genes for leaf growth and development, such as ROT3 gene, should be useful tools for the biodesign of plant organs.

• Proceedings of the Korean Society of Plant Biotechnology Conference
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• 2003.04a
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• pp.49-55
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• 2003

The morphology of the leaves and the flowers of angiosperms exhibit remarkable diversity. One of the factors showing the greatest variability of leaf organs is the leaf index, namely, the ratio of leaf length to leaf width. In some cases, different varieties of a single species or closely related species can be distinguished by differences in leaf index. To some extent, the leaf index reflects the morphological adaptation of leaves to a particular environment. In addition, the growth of leaf organs is dependent on the extent of the expansion of leaf cells and on cell proliferation in the cellular level. The rates of the division and enlargement of leaf cells at each stage contribute to the final shape of the leaf, and play important roles throughout leaf development. Thus, the control of leaf shape is related to the control of the shape of cells and the size of cells within the leaf. The shape of flower also reflects the shape of leaf, since floral organs are thought to be a derivative of leaf organs. No good tools have been available for studies of the mechanisms that underlie such biodiversity. However, we have recently obtained some information about molecular mechanisms of leaf morphogenesis as a result of studies of leaves of the model plant, Arabidopsis thaliana. For example, the ANGUSTIFOLIA (AN) gene, a homolog of animal CtBP genes, controls leaf width. AN appears to regulate the polar elongation of leaf cells via control of the arrangement of cortical microtubules. By contrast, the ROTUNDIFOLIA3 (ROT3) gene controls leaf length via the biosynthesis of steroid(s). We provide here an overview of the biodiversity exhibited by the leaf index of angiosperms. Taken together, we can discuss on the possibility of the control of the shapes and size of plant organs by transgenic approaches with the results from basic researches. For example, transgenic plants that overexpressed a wild-type ROT3 gene had longer leaves than parent plants, without any changes in leaf width. Thus, The genes for leaf growth and development, such as ROT3 gene, should be useful tools for the biodesign of plant organs.

• International Journal of Industrial Entomology and Biomaterials
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• v.5 no.1
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• pp.131-134
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• 2002

Mulberry being the only food of silkworm, Bombyx mori L., is of great economic importance to the silk industry, The success in cocoon production mainly depends on the supply of quality leaves in sufficient quantity. In mulberry, where the economic product is leaf, the uptake of nitrogen from soil is very heavy and high responses to application of nutrients have been reported. Nitrogen supports vegetative growth particularly the leaf biomass. Variation in nitrogen harvest index and other physiological and yield contributing traits were estimated in five mulberry genotypes. Considerable variation was observed for nitrogen harvest index, protein yield per plant and harvest index. The correlation studies indicated the protein yield per plant was significantly correlated with leaf yield, nitrogen content in leaf, nitrogen harvest index and harvest index. The broad sense heritability estimates revealed that harvest index showed highest heritability (88.07%) followed by nitrogen content (82.52%), protein yield (70.28%) and nitrogen harvest index (66.52%).

• Journal of Plant Biotechnology
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• v.38 no.4
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• pp.285-292
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• 2011

In plants, heteroblasty reflects the morphological adaptation during leaf development according to the external environmental condition and affects the final shape and size of organ. Among parameters displaying heteroblasty, leaf index is an important and typical one to represent the shape and size of simple leaves. Leaf index factor is eventually determined by cell proliferation and cell expansion in leaf blades. Although several regulators and their mechanisms controlling the cell division and cell expansion in leaf development have been studied, it does not fully provide a blueprint of organ formation and morphogenesis during environmental changes. To investigate genes and their mechanisms controlling leaf index during leaf development, we carried out molecular-genetic and physiological experiments using an Arabidopsis mutant. In this study, we identified macrophylla (mac) which had enlarged leaves. In detail, the mac mutant showed alteration in leaf index and cell expansion in direction of width and length, resulting in not only modification of leaf shape but also disruption of heteroblasty. Molecular-genetic studies indicated that mac mutant had point mutation in ROTUDIFOLIA3 (ROT3) gene involved in brassinosteroid biosynthesis and was an allele of rot3-1 mutant. We named it mac/rot3-5 mutant. The expression of ROT3 gene was controlled by negative feedback inhibition by the treatment of brassinosteroid hormone, suggesting that ROT3 gene was involved in brassinosteroid biosynthesis. In dark condition, in addition, the expression of ROT3 gene was up-regulated and mac/rot3-5 mutant showed lower response, compare to wild type in petiole elongation. This study suggests that ROT3 gene has an important role in control of leaf index during leaf expansion process for proper environmental adaptation, such as shade avoidance syndrome, via the control of brassinosteroid biosynthesis.

• Progress in Medical Physics
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• v.15 no.4
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• pp.173-178
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• 2004

Purpose: To compare desimetrically intensity-modulated radiotherapy treatment plans with commercially available multileaf collimators (MLCs) of different leaf width for intracranial lesions. Materials and Methods: Twelve patients with intracranial lesions were treated with BrainLAB's micro-MLCs (mMLCs) and performed with the BrainSCAN ver. 5.2 planning software. They were replanned using the Varian 120 and 80 MLCs. These collimators have minimum leaf width of 3 mm, 5 mm and 10 mm at isocenter, respectively. PTV was $3.3~339.2\textrm{cm}^3$ and the number of beams was 3~7. These three plans were compared with respect to the uniformity and the conformity indices, doses to critical organ and normal tissue. Results: For the uniformity index of the planning target volume (PTV), there were no statistically significant differences between mMLCs and 120 MLCs (p=0.057) and between 120 MLCs and 80 MLCs (p=0.388). However, there was a difference between mMLCs and 80 MLCs (p<0.001). Maximum target dose to the PTV showed no dependency with respect to the leaf width. On the contrary, there were statistically significant differences in the conformity indices between mMLCs and 120 MLCs (p=0.003), between mMLCs and 80 MLCs (p=0.003) and between 120 MLCs and 80 MLCs (p=0.003). The volume of brainstem irradiated to $\geq$70% dose and to $\geq$50% dose was increased as the leaf width of MLCs increased. In particular, the volume of normal tissue irradiated is obviously changed for different leaf width. Volumetric increments for MLCs with leaf widths of 5 mm and 10 mm were 6.3% and 23.2% to the normal tissue irradiated to $\geq$50% dose, and 8.7% and 32.7% to the normal tissue irradiated to $\geq$70% dose, respectively, compared to the volume for MLCs with leaf width of 3 mm. Conclusions: The uniformity index and maximum target dose to the PTV showed no dependency with respect to leaf width of MLCs. However, the conformity index was improved as the leaf width decreased. For the sparing of normal brain tissue, treatment plans with MLCs of 3 mm leaf width is more effective, compared to ones with MLCs of 5 mm and 10 mm leaf widths.

• Journal of Plant Biotechnology
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• v.33 no.2
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• pp.111-115
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• 2006

This study was carried out to establish genetic transformation of Rot 3 gene into perilla plants and to evaluate aromatic compounds, brightness, anthocyanin contents and leaf index in Rot 3 overexpressing transgenic lines. Rot 3 transmitted successfully from T$_1$ to T$_2$ generation showing stable gene expression. It revealed that there was no difference between transgenic and non-transgenic plants in major agronomic characteristics of progeny analysis. There was not much difference in aromatic compounds and leaf brightness did not showed variations between transgenic and non-transgenic, but leaf index was distinguished, respectively.

• Proceedings of the Korean Society of Medical Physics Conference
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• 2004.11a
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• pp.126-129
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• 2004

We compared intensity-modulated radiotherapy (IMRT) treatment plans with commercially available multileaf collimators (MLCs) of different leaf width for intracranial lesions. Twelve cases previously treated with micro-MLCs(mMLCs) were replanned using the Varian 120 and 80 MLCs. These collimators have minimum leaf width of 3mm, 5 mm and 10 mm at isocenter, respectively. These three plans were compared with respect to the uniformity and the conformity indices, doses to normal tissue. For the uniformity index of planning target volume (PTV),there was no statistically significant difference between mMLCs with 120 MLCs (p = 0.06). However, there was a little difference between mMLCs with 80 MLCs (p = 0.001). Maximum target dose to the PTV showedno dependency with respect to the leaf width. On the contrary, there were statistically significant differences in the conformity indices between mMLCs and 120 MLCs (p = 0.003) and between mMLCs and 80 MLCs (p = 0.003).The volumetric increments for MLCs with leaf widths of 5 mm and 10 mm were 6.3% and 23.2% for the normal tissue Irradiated to = 50% dose, and 8.7% and 32.7% for the normal tissue Irradiated to = 70% dose, respectively, compared to the volume for MLCs with leaf width of 3 mm. This shows that for the sparing of normal tissue, MLCs with leaf width of 3 mm are more effective, compared to MLCs with leaf widths of 5 mm and 10 mm.

• Journal of Ginseng Research
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• v.15 no.1
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• pp.31-35
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• 1991

In order to know the optimum planting density under shading structures at different light intensity, We investigated the growth status, distribution of ginseng leaf area, correlation between planting density and root weight per plant and yield, correlation between leaf area index and root weight per plant and yield. According to the increase of planting density the leaf area per plant was decreased, but leaf area index (L.A.I) was increased. Ginseng leaf population at different lines under common straw shading were distributed mainly in frost lines but polyethylene net shading at 10fo light intensity were distributed equally in all lines. Optimum planting density in common straw shading at 5% light intensity was 55 plant per tan (90 cmX180 cm) and polyethylene net shading 81 10% light intensity was 60 plant per tan, in consideration of root weight and yield. Optimum leaf area index was 2.4 under common straw shading at 5% light intensity but was 2.7 under polyethylene net shading at 10% light intensity.

• Journal of the Korean Society of Tobacco Science
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• v.14 no.1
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• pp.48-56
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• 1992

This studies were carried out to investigate the effects of leaf loading quantity and circulating air volume during bulk curing on the variation of physical and chemical characteristics in flue-cured tobacco. The results are as follows : 1. The content of sugar in cured leaves was decreased with more circulating air volume and leaf loading quantity at bulk curing. 2. Total nitrogen and protein nitrogen were decreased with less circulating air volume and more leaf loading quantity, while amino nitrogen was increased. 3. The contents of linolenic acid and linoleic acid were increased with more leaf loading quantity and oxalic acid and citric acid had a tendency of being increased in case of high circulating air volume. 4. In general, major aromatic compounds were increased through flue-curing. Relatively high content of solanone in case of lower air volume and less leaf loading were observed, while megastig matrienone was increased when leaf loading was small. 5. The more circulation air volume with leaf loading quantity caused lowering equilibrium moisture content and higher shatter index, which resulted in poor quality of cured leaves based on quality index, nitrogen number, taste index phillips index, and sugar-nicotine ratio.