• Korean Journal of Microbiology
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• v.48 no.1
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• pp.16-21
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• 2012

Since many pesticides cause various health and environmental problems, alternative measures to replace them are needed, and the bacteria producing the antifungal substances can be one of them. In this study, several rhizobacteria were isolated and their antifungal activities against some important plant pathogenic fungi were examined. Pseudomonas otitidis TK1 and Paenibacillus peoriae RhAn32 inhibited the growth of Fusarium oxysporum f. sp. niveum and F. oxysporum f. sp. lycopersici by 49.8% and 45.6%, and 45.1% and 48.3%, respectively compared to those of the control. P. peoriae RhAn32 also decreased the growth of F. oxysporum f. sp. raphani by 37.5%. This growth inhibition might be due to the production of antifungal substances, such as siderophore, hydrogen cyanide and chitinase, which were produced by these rhizobacteria. P. otitidis TK1 also produced plant growth hormones indole acetic acid and indole butyric acid at $293.41{\mu}g/mg$ protein and $418.53{\mu}g/mg$ protein, respectively. When P. otitidis TK1 and B. cereus TK2 were inoculated together with F. oxysporum f. sp. lycopersici to the 4 weeks grown tomato seedlings and incubated additional 8 weeks, the stem lengths of tomato increased up to 45.7% and 55.3% and root lengths were raised to 64.9% and 60.8%, respectively than those of the control group. The wet weights increased by 118% and 182%, respectively compared to the control group.

• Horticultural Science & Technology
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• v.33 no.2
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• pp.227-232
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• 2015

This experiment was carried out to investigate the effects of shading materials (aluminum specific-shading screen and polypropylene non-woven fabric) and shading ratio (50% and 70%) on climatic changes, cut-flower quality, and yield of spray rose cultivars for export during high temperature periods. The daily cumulative solar radiations were higher with the aluminum specific-shading screen, especially with 50% shading compared to polypropylene non-woven fabric. Air temperature and root zone temperature within rockwool media greatly decreased with the aluminum specific-shading screen, but relative air humidity was not different among shading methods. Chlorophyll contents (SPAD values) were slightly higher with aluminum-specific shading screen than with polypropylene non-woven fabric, and were higher with 50% than with 70% aluminum specific-shading screen. Except for 'Lovely Lydia', marketable and exportable yields of all cultivars were higher with 50% than with 70% aluminum shading treatment. In addition, flowers talk length, stem diameter, number of node and 7ea-leaflet, and floret number tended to be better with aluminum specific-shading screen. Flower stalk length was higher with 70% than with 50% aluminum shading treatment. Chromaticity of petals slightly increased, and vase life was 0.5-2.5 days longer for each cultivar with aluminum specific-shading screen than with polypropylene non-woven fabric.

• Korean Journal of Medicinal Crop Science
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• v.21 no.1
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• pp.20-26
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• 2013

This study was conducted to improve the managing and storing methods of the seeds of Aralia cordata var. continentalis (Kitagawa) Y.C.Chu, to examine the viability and the germination ability of seeds with different storing conditions and methods, and to develop new ways to propagate and have better healthy seedling. Therefore, the germination rate, days required for germinating seeds, and early growth responses of Aralia cordata var. continentalis (Kitagawa) Y.C.Chu were investigated with different storing temperatures, durations and methods. The germination rate was higher in stratified storage than that in dry storage condition. The highest germination rate was with outdoor temperature at 30 days after stratified storage. The days required for germinating seeds were less than 10 days with the treatment of $25^{\circ}C$ and outdoor temperature in stratified storage. In dry condition, they were shorter with $4^{\circ}C$ and $25^{\circ}C$ than those with $-20^{\circ}C$ and outdoor temperature. Leaf number of seedling was higher in stratified storage compared to that in dry condition, while it was not clearly different according to storage temperatures and durations. Leaf length and leaf width of seedling was not difference among the treatment of storage methods, temperatures, and durations. Stem length of seedling was higher in stratified storage than those in dry condition, while root length was not clearly different among the treatments. It would be assumed that temperatures, methods and durations of storage could affect much to the germination rate and the early seedling growth response.

• The Plant Pathology Journal
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• v.32 no.2
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• pp.112-122
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• 2016

Virus-induced gene silencing (VIGS) is an effective tool for the study of soybean gene function. Successful VIGS depends on the interaction between virus spread and plant growth, which can be influenced by environmental conditions. Recently, we developed a new VIGS system derived from the Soybean yellow common mosaic virus (SYCMV). Here, we investigated several environmental and developmental factors to improve the efficiency of a SYCMV-based VIGS system to optimize the functional analysis of the soybean. Following SYCMV: Glycine max-phytoene desaturase (GmPDS) infiltration, we investigated the effect of photoperiod, inoculation time, concentration of Agrobacterium inoculm, and growth temperature on VIGS efficiency. In addition, the relative expression of GmPDS between non-silenced and silenced plants was measured by qRT-PCR. We found that gene silencing efficiency was highest at a photoperiod of 16/8 h (light/dark) at a growth temperature of approximately $27^{\circ}C$ following syringe infiltration to unrolled unifoliolate leaves in cotyledon stage with a final SYCMV:GmPDS optimal density $(OD)_{600}$ of 2.0. Using this optimized protocol, we achieved high efficiency of GmPDS-silencing in various soybean germplasms including cultivated and wild soybeans. We also confirmed that VIGS occurred in the entire plant, including the root, stem, leaves, and flowers, and could transmit GmPDS to other soybean germplasms via mechanical inoculation. This optimized protocol using a SYCMV-based VIGS system in the soybean should provide a fast and effective method to elucidate gene functions and for use in large-scale screening experiments.

• Applied Biological Chemistry
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• v.40 no.2
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• pp.134-138
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• 1997

The objective of this study was to examine the effect of phosphorus deficiency on nitrogen fixation and photosynthesis of nitrogen fixing soybean plant under $CO_2$ enrichment condition. The soybean plants(Glycine max [L.] Merr.) inoculated with Bradyrhizobium japonicum MN 110 were grown with P-stressed(0.05 mM-P) and control(1 mM-P) treatment under control$(400\;{\mu}l/L\;CO_2)$ and enrichment$(800\;{\mu}l/L\;CO_2)$ enviromental condition in the phytotron equipped with high density lamp$(1000\;{\mu}Em^{-2}S^{-1})$ and $28/22^{\circ}C$ temperature cycle for 35 days after transplanting(DAT). At 35 DAT, phosphorus deficiency decreased total dry mass by 64% in $CO_2$ enrichment condition, and 51% in control $CO_2$ condition. Total leaf area was reduced significantly by phosphorus deficiency in control and enriched $CO_2$ condition but specific leaf weight was increased by P deficiency. Phosphorus deficiency significantly reduced photosynthetic rate(carbon exchange rate) and internal $CO_2$ concentration in leaf in both $CO_2$ treatments, but the degree of stress was more severe under $CO_2$ enrichment condition than under control $CO_2$ environmental condition. In phosphorus sufficient plants, $CO_2$ enrichment increased nodule fresh weight and total nitrogenase activity(acetylene reduction) of nodule by 30% and 41% respectively, but specific nitrogenase activity of nodule and nodule fresh weight was not affected by $CO_2$ enrichment in phosphorus deficient plant at 35 DAT. Total nitrogen concentrations in stem, root and nodule tissue were significantly higher in phosphorus sufficient plant grown under $CO_2$ enrichment, but nitrogen concentration in leaf was reduced by 30% under $CO_2$ enrichment. These results indicate that increasing $CO_2$ concentration does not affect plant growth under phosphorus deficient condition and phosphorus stress might inhibit carbohydrate utilization in whole plant and that $CO_2$ enrichment could not increase nodule formation and functioning under phosphorus deficient conditions and phosphorus has more important roles in nodule growth and functioning under $CO_2$ enrichment environments than under ambient condition.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.56 no.3
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• pp.183-191
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• 2011

This study was undertaken to collect basic knowledge of Jatropha which is one of bio-energy crops, based on the understanding of physiological and molecular aspects under salt and drought conditions. The treatments were followed as: 100, 200 and 300 mM NaCl for salt stress and 5, 10, 20 and 30% PEG for drought stress for 8 days, respectively. Leaf growth, stomatal conductance, chlorophyll fluorescence and gene expression of aquaporin (JcPIP2) of Jatropha were investigated. From 2 days after treatments, plants treated with higher than 100 mM NaCl and 10% PEG respectively were significantly suppressed in leaf length, width, and stomatal conductance, but 5% PEG treatment showed that plant growth was improved more than control plant. Semi-quantitative RT-PCR analyses revealed that the JcPIP2 gene was expressed in root, stem, cotyledon and leaves. It was not detected in leaves at 200 and 300 mM NaCl treatments. However, transcripts of JcPIP2 were induced in roots and stems under salt and drought conditions compared to those of healthy plants. Therefore, it was concluded that JcPIP2 plays an important role in improving drought tolerance.

• Korean Journal of Plant Taxonomy
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• v.38 no.4
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• pp.433-458
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• 2008

This study were examined for their external morphological characters such as root, leaf, inflorescenses, flower, stamen, pistil, and fruit as to Korean Thalictrum L. and discussed taxanomic value of characters, and made out a new key. This study confirmed that specialized stems and roots type were divided into fibrous type, fibrous having a tuber type, long fusiform tuberous type, tuberoid type, rhizome type and stolon type. The stem were divided into two types based on existence and nonexistence of striate or pubescent. Leaves were usually 2-3-ternately and was divided into three types based on leaf apex, leaf base and number of lobe. Inflorescenses were divided into two type; corymb, panicle. Flower is bisexual, and don't have petal. It was divided from existence and nonexistence of calyx when it flowering. Especially, the stamens were divided from anther shape and apex shape, degree of dilation of filament, epidermic shape of filament etc., and the pistils were divided from glandular on ovary, length of carpel stipe etc.. The fruit is a achene and it was divided from achene shape, achene rib or wings, achene stipe length. This study suggest that useful characters for identifying section are degree of dilation of filament, anther shape, achene rib and wings, degree of dilation of achene. Also, roots, leaf shape, stamen and pistil shape, achene beak and achene length, achene and leaf hair appear to be useful characters for identifying species.

• Korean Journal of Food Science and Technology
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• v.44 no.1
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• pp.100-105
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• 2012

Analysis of the various constituents and determination of biological activities in the different parts (root, stem, and leaf) of Allium victorialis var. platyphyllum were carried out. Potassium and calcium were detected in higher contents (mg/100 g fresh wt.) than other minerals. The total phenolic content (mg tannic acid eq./100 g dry wt.) decreased in the order of leaves ($792.7{\pm}16.6$) > stems ($160.3{\pm}6.8$) > roots ($101.5{\pm}2.7$), and the total flavonoid content (mg quercetin eq./100 g dry wt.) was as follows: leaves ($497.9{\pm}11.1$), roots ($35.7{\pm}0.4$), stems ($18.5{\pm}1.4$). DPPH radical-scavenging activity and inhibition activity against the formation of cholesteryl ester hydroperoxide in rat blood plasma was higher in the leaves than in roots and stems. Extracts of A. victorialis separated by parts displayed antimicrobial activity against Clostridium perfringens, Staphylococcus aureus, Listeria monocytogenes, Vibrio vulnificus, Vibrio parahaemolyticus, of which the strongest activity was against C. perfringens.

• Journal of Bio-Environment Control
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• v.31 no.3
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• pp.212-220
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• 2022

When it comes to single node leafy stem cuttings of rose (Rosa hybrida), environmental management such as air temperature, relative humidity, and light affect productivity. In order to investigate the effect of air temperature and relative humidity on the cutting success rate and rooted cuttings quality, a transparent airtight box was used to implement a closed system. We have also tried to find out the most effective photoperiod and the number of leaflets in closed system using artificial light (white LED, 104.0 µmol·m^-2·s^-1 photosynthetic photon flux density). The first experiment was conducted for a total of 6 weeks under 4 airtight period conditions. The number of roots and longest root length decreased as the airtight period increased. But there were no significant differences in the survival rate, shooting rate, and rooting rate according to airtight periods. In the second experiment the results indicated that survival and shooting rate were significantly affected by the photoperiod (0/24, 2/22, 4/20, 8/16, and 16/8 h), the number of leaflets (0, 2, and 4 leaflets) of the cuttings and their interaction. The survival rate was the highest in the 16-h day length and 4 leaflets. By considering survival rate and shooting rate with energy efficiency, the 8-h day length and 2 or 4 leaflets were judged to be the most effective.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.68 no.3
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• pp.207-215
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• 2023

This study was compared the soil environment and growth and yield of onion (Allium cepa L.) treated with non-mulching (NM) and mulching polyethylene film (PEF) and two biodegradable films (BFI and BFII) commonly used in farmhouses. Visual observation confirmed the degradation of BFI and BFII films after 150 days after tansplanting (DAT). BFII increased light penetration into the films and reduced the weight maintenace after 180 DAT, with a high decompostion at 30 days after soil tilling. Soil moisture contents much fluctuated between -14 kP and - 0 kPa in NM plots, increasing the minimum soil temperature of BFI plots. Mulching treatments decreased soil organic matter contents but did not subtantially increase soil mineral nutrients, soil bulk density, and number of bacteria compared to those of NM plots. Onion root growth was increased by PEF and BFI treatments at an early growth stage, 60 DAT, with the most remarkable stem extension observed for PEF and BFI treatments after 150 DAT. PEF and BFI treatments increased the bulb's diameter, length, weight, and lodging at 180 DAT. BFI treatments exhibited a high portion of the "very large" category producing with 55.3 tons ha^-1 based on the classification into bulb size, followed by PE (49.3 tons), NM (9.4 tons), and BFII treatments (2.7 tons) at 230 DAT.