• FLOWER RESEARCH JOURNAL
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• v.18 no.1
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• pp.9-14
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• 2010

This study was conducted to examine the effects of IAA and kinetin on induction of gemmae and gametophytes in Hypnum plumaeforme moss during tissue culture. Explants were obtained from sterilized gametophyte tips cultured on solid basal medium containing Knop's major salts and Nitsch and Nitsch's trace elements. After culture, inoculated gametophyte tip produced protonema firstly, changed to new gametophytes after four weeks. Aseptic gametophytes were chopped and inoculated on the same media containing 0.01, 0.1, 1 and $10{\mu}M$ of IAA and kinetin. As a result, secondary protonemata as well as protonemal gemmae were formed from gametophytes. But protonemal gemmae formation was varied according to the concentration of IAA and kinetin. Lower concentration of IAA and kinetin promoted gemma formation and bud induction. Especially, $0.01{\mu}M$ of kinetin showed the highest frequency of bud and gemma production. All the materials, obtained from $0.01{\mu}M$ kinetin medium, were subcultured to media supplemented with 0.01, 0.1, 1 and $10{\mu}M$ of IAA and kinetin again to induce gametophytes. After subculture, protonema and calli were developed from secondary protonema, and induced gametophytes finally. IAA regulated induction and growth of gametophytes, and kinetin influenced gemma formation and gametophyte induction also. All aspects of development of this moss species were governed by the external growth regulators.

• Korean Journal of Agricultural and Forest Meteorology
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• v.23 no.4
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• pp.349-355
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• 2021

The effect of night temperature was investigated on mango (Mangifera indica cv. Irwin) for setting appropriate night temperature and managing mango cultivation in a greenhouse. Different night temperatures (10, 15, and 20℃) were treated from budding to fruit development in mango trees. As night temperature increased, the initiation of flowering, full blooming, fruiting, and fruit development tended to be accelerated. There were no significant differences in the growth of shoots flushed after the fruit harvest among trees treated with different night temperatures. The lengths of the flower stalk were the shortest at 10℃ of night temperature; however, there were no significant differences between 15℃ and 20℃ of the night temperature. The length, diameter, and weight of mango fruits were higher at 15℃ and 20℃ than 10℃. Soluble solid contents and acidities showed no difference; the firmness and skin color were better as the night temperature increased. Accordingly, setting the minimum night temperatures to 15℃ or 20℃ can increase the number of fruits and produce high-quality fruits when cultivating mango in the greenhouse. Even the minimum night temperature to 15℃ can reduce heating costs in the greenhouse.

• Korean Journal of Crystallography
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• v.5 no.2
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• pp.51-66
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• 1994

Y3Al5O2 and Nd: Y3Al5012 single crystals were grown by Czochralskl technique. The effectt of pulling rate rotation rate, and doping level of Nd3+ ion on the crystal quality were studied Various types of defects were analysed by photo-elastic effect and chemical etching method Finally, spectroscopic and laser poputies of grown crystal were measured. Optirmum pulling rate for good quality was dependant on the doping level of Nd3+ ion. It was found that the suitable pulling rates for pure Y3Al5O12 for 3.0∼3.5 a/o Nd3+ ion doped Y3Al5012 and for more than 40 a/o Nd3+ ion doped Y3Al5012 were 2∼4mm/hr, 0.6∼0.5mm/hr, and less than 0.4mm/hr respectively. Solid-liquid interface was convex at the rotation rate of 27∼60rpm, and concave at the rotation rate of 80∼100rpm. Growth axis was confired to <111> direction and lattice parameter was measured to 12.017A. Core (211) facets,striations, inclusions of metal particles, dislocations and optical inhonngeneities were detected. Four level laser transition of Nd3+ion in YIAls012 single crystal were identified by the spectroscopic measurements. Laser rod with tam diameter and 63mm length was fabricated from grown Nd3+ Y3Al5012 sin91e crystals. 1.8lJ of lasing threshould and 0.49% of soope efficiency were measured by the Pulsed laser action.

• Horticultural Science & Technology
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• v.35 no.4
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• pp.393-401
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• 2017

One-year old pear (Pyrus pyrifolia L.) trees of a new commercial cultivar 'Manpungbae', recently developed in South Korea, were planted in 2001 (planting year 1) and trained to four trellis systems: Y-trellis, Y-II-trellis, pergola, and vase-pergola. To evaluate training systems in the local area (southern Korea), tree growth responses were compared for each trellis system from planting years 3 to 8. For trees trained to Y-trellis and pergola systems, a high proportion of land covered by tree canopy was maintained over the study duration, with 70-80% coverage in year 8. Eight-year cumulative yield per tree was increased in the vase-pergola system with a low planting density and an additional scaffold. Compared with other systems, cummulative yield use efficiency was greatest in Y-II-trellis and pergola systems in years 5 and 8. Compared with Y-II-trellis and vase-pergola systems, the 8-year cumulative yield per hectare was two fold greater for trees trained to the Y-trellis (103 tons) and pergola systems (101 tons). Use of the pergola system improved average fruit weight and fruit soluble solid contents, as well as net income in year 8. Given that we observed reduced fruit productivity and increased labor hours (pruning and orchard work), we consider the Y-trellis and pergola systems to be less valuable trellis systems than the others evaluated.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.25 no.2
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• pp.74-79
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• 2015

$Na-ZnCl_2$ battery, which operates as the same mechanism of $Na-NiCl_2$ battery using solid-electrolyte, is able to reduce its material cost by 40 % comparing to the $Na-NiCl_2$ battery. It has been known that the $Na-ZnCl_2$ battery produces $Na_2ZnCl_4$ as an intermediate phase during charge/discharge process. Therefore, the redox process is divided into four steps having the voltage range of 1.92~2.13 V. However, effects of the critical factors such as the composition of cathode materials, depth of charge and discharge, and additives have not been reported yet. We examined the effect of the Zn/NaCl ratios and revealed that its optimum ratio was in the range of 1.3~1.7.

• Microbiology and Biotechnology Letters
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• v.38 no.2
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• pp.129-135
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• 2010

We described production of bioactive compounds from fungi grown on Korean ginseng-steaming effluents (GSE) for develop high-value added nutraceuticals from Korean GSE. Hansenula anomala KCCM 11473, which grew well in Korean GSE had high RNA content, and its optimal autolysis conditions were established to produce 5'-ribonucleotides (13.9~28.5 mg/g of biomass) at $55^{\circ}C$ and pH 5.0 for 24 h. 5'-Phosphodiesterase and adenyl deaminase were not effective in increasing the yield of 5'-ribinucleatides, but the yield of IMP increased significantly only after the addition of 1.0% adenyl deaminase. Saccharomyces cerevisiae showed the highest growth in the GSE medium. 267.1 mg of S. cerevisiae biomass was produced from 1 g of GSE solid and medicinal ginsenoside-$Rg_3$ contents was determined with 0.033 mg. Mucor miehei KCTC 6011 produced approximately 120 mg of chitosan per g-dry mycelium in 84 h at $25^{\circ}C$ when grown in the GSE (pH 8.0) supplemented with 0.5% yeast extract and 0.002% $CuSO_4$. Chitosan produced by M. miehei KCTC 6011 have deacetylated approximately 56% and its viscosity and molecular weight of the chitosan were 80 cps and $1.07\times10^3$ kDa, respectively. The chitosan at 1.5 mg/ml inhibited 73.9% of the mycelium growth of Rhizotonia solani in 60 h.

• Korean Journal of Organic Agriculture
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• v.27 no.1
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• pp.45-56
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• 2019

The study I was initiated in six private 'Campbell Early' vineyards in parts of Jeollanam-do province to relieve symptom of fruit blight mostly due to a high temperature occurred in Summer. High percentage of fruit blight was observed for medium growth of grape trees non-irrigated. In the study II, grape trees treated with 0%, 30% and 60% shade films were investigated for the tree responses, including fruit blight symptom in the research plots. Harvesting time was advanced approximately two weeks by the 30% shade treatment. High percentage of shades increased total shoot length per tree and decreased shoot diameter, with the greatest number of shoots observed for the 30% shade-treated grapes. Light intensity in the tree canopy was approximately 26% decreased by 30% shade treatment. Marketable harvested fruits per tree were 50.6 of 30% shade treatment, 33.6 of 0% shade, and 42.8 of 60% shade. The 30% shade treatment decreased to 11.8% of cluster blight per tree and to 11.2% of berry blight per cluster. The 30% shade treatment increased cluster weight, berry weight, soluble solid contents, and anthocyanin contents.

• FLOWER RESEARCH JOURNAL
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• v.17 no.1
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• pp.9-14
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• 2009

This study was conducted to find out the commercial in vitro propagation methods through protocom-like bodies (PLB) induced from shoot tip culture of Miltonia spp. Among several culture media for induction PLB from shoot tip in Miltonia spp., MS basal medium was better than Hyponex, Vacin & Went basal medium and other media supplemented with natural additives. PLB's proliferation and differentiation in Hyponex medium including $20g{\cdot}L^{-1}$ banana + $20g{\cdot}L^{-1}$ sucrose(pH 5.2) was better than in MS medium. It was tendency that solid media showed higher PLB fresh weight than liquid medium or other cotton bridge culture. The dark culture for 1~2 weeks and adding $10{\sim}20g{\cdot}L^{-1}$ sucrose on hyponex basal medium was the most effective to increase the PLBs growth and shoot number.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.21 no.4
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• pp.175-180
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• 2011

The doping effect of Cu in the Sr-doped lanthan manganites (LSM) has been investigated in terms of structural analysis and thermal expansion coefficient (TEC). The $La_{0.8}Sr_{0.2}Mn_{1-x}Cu_xO_3$ ($0{\leq}x{\leq}0.3$) were prepared by solid state reaction method and their crystal structure and TEC were measured. A decrease in the lattice parameters and the TEC were observed with increase eu content, whereas they were decreased for x = 0.3. For $0{\leq}x{\leq}0.2$, the decrease of the lattice parameter and the TEC with increase Cu content were attributed to the reduction of ionic radius of Cu ions due to the presence of $Cu^{3+}$ ions. For x = 0.3, however, the increase was originated from the formation of oxygen vacancies due 10 the presence of $Cu^{2+}$ and $Mn^{4+}$.

• Horticultural Science & Technology
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• v.28 no.5
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• pp.796-801
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• 2010

This study was carried out to establish a system for mutation breeding by irradiation of gamma-ray in $Rosa$ $hybrida$ Hort. The rooted cuttings of two roses, 'Spidella' and 'Cabernet' were irradiated with different gamma-ray doses (0, 30, 50, 70, 90, 110, 130, 150 and 170 Gy) from a $^{60}Co$ source to reveal an optimal dose for induction of mutants. The irradiated plants were planted in a greenhouse, and investigated on the appearance of petal color mutants and shoot growth by gamma ray dose. The 50% lethal doses ($LD_{50}$) of plant were 110 Gy for 'Spidella' and 150 Gy for 'Cabernet', respectively. The 50% decrease dose of shoot length was observed at 70-90 Gy dose for 'Spidella', and 110 Gy dose for 'Cabernet'. Solid, chimeric and mosaic petal mutants with various colors were induced from pink petal of 'Spidella' and red petal of 'Cabernet' when 30-170 Gy dose was irradiated. The mutants obtained from 'Spidella' had white, ivory, pinky ivory, light pink and deep pink petal colors. The mutants obtained from 'Cabernet' had pink, deep pink, purple red (magenta), orange red and purple petal colors. It was suitable to irradiate 70-90 Gy dose for 'Spidella' and 90-110 Gy dose for 'Cabernet' for the induction of various mutants considering plant survival rate, shoot growth and mutant occurrence rate.