• Journal of Bio-Environment Control
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• v.14 no.4
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• pp.275-279
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• 2005

The fruiting habit pattern of white-spine cucumber, whose fruits are usually borne on the lateral branches, is different from domestic ones. The cucumber production far export has been focused on how to promote lateral shooting and how to increase the number of lateral branches. As the growing season of the exporting cucumber is confined to winter season, low temperature and weak light are limiting factors to lateral shooting. This study was conducted to investigate the effect of foliar application of growth regulator for induction of lateral shoot in white-spine cucumber. foliar application of growth regulator were focused on concentration and application time based on number of leaves. The visible damages were observed in applied leaves by $30mg{\cdot}L^{-1}$ BA(benzyladenine) in retarding culture, but no significant by $10mg{\cdot}L^{-1}$ BA in case of semi-forcing culture. The number of available lateral shoots were greater in applied plant with $10mg{\cdot}L^{-1}$ BA than that of $30mg{\cdot}L^{-1}$ BA, in applied plants at 10th and 15th loaves than that of applied plants at 5th leaves.

• Journal of Wetlands Research
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• v.16 no.1
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• pp.11-18
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• 2014

The effect of elevated $CO_2$ and temperature on ecological characteristics of Cicuta virosa L., the endangered plant were examined under ambient $CO_2$+ambient temperature(AC-AT), ambient $CO_2$+elevated temperature(AC-ET) and elevated $CO_2$+elevated temperature for two years. Shoot length and the number of umbels were not different in three environmental gradients. The number of tillers was high in the order of EC-ET, AC-ET and AC-AT. The number of compound umbel was the lowest in the EC-ET. Fruit set rate was the highest in the AC-AT. These results mean that unsexual propagation of C. virosa may increase by promoting growth of tillers, rather than seed production under future global warming. This population growth study will be used as the important data for the research of Korean endangered species.

• Journal of Ginseng Research
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• v.39 no.3
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• pp.213-220
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• 2015

Background: Korean ginseng (Panax ginseng Meyer) is a perennial herb prone to various root diseases, with Phytophthora cactorum being considered one of the most dreaded pathogens. P. cactorum causes foliar blight and root rot. Although chemical pesticides are available for disease control, attention has been shifted to viable, eco-friendly, and cost-effective biological means such as plant growth-promoting rhizobacteria (PGPR) for control of diseases. Methods: Native Bacillus amyloliquefaciens strain HK34 was isolated from wild ginseng and assessed as a biological control agent for ginseng. Leaves from plants treated with HK34 were analyzed for induced systemic resistance (ISR) against P. cactorum in square plate assay. Treated plants were verified for differential expression of defense-related marker genes using quantitative reverse transcription polymerase chain reaction. Results: A total of 78 native rhizosphere bacilli from wild P. ginseng were isolated. One of the root-associated bacteria identified as B. amyloliquefaciens strain HK34 effectively induced resistance against P. cactorum when applied as soil drench once (99.1% disease control) and as a priming treatment two times in the early stages (83.9% disease control). A similar result was observed in the leaf samples of plants under field conditions, where the percentage of disease control was 85.6%. Significant upregulation of the genes PgPR10, PgPR5, and PgCAT in the leaves of plants treated with HK34 was observed against P. cactorum compared with untreated controls and only pathogen-treated plants. Conclusion: The results of this study indicate HK34 as a potential biocontrol agent eliciting ISR in ginseng against P. cactorum.

• Korean Journal of Soil Science and Fertilizer
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• v.32 no.1
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• pp.57-61
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• 1999

This study measured the soaking effects of two brassinosteroids(BRs), homobrassinolide(hBR : 225, 23S-homobrassinolide) and epibrassinolide(epiBR : 22R, 23R. 24R-$2{\alpha}$, $3{\alpha}$, 22, 23-Tetrahydroxy-B-homo-7-oxa-$5{\alpha}$-ergostan-6-one) on the germination of two rice cultivars, 'Milyang 23' and 'Naepungbyeo' exposed to simulated acid rain(SAR). The results suggested that promoting effect of two BRs on alleviating damage to SAR would be attributed to the promotion of plant growth, root elongation, and particularly germination rate of both cultivars. Eight organic acids were determined by HPLC. Succinic acid acetic acid in 'Milyang 23' under SAR were highest among eight organic acids.

• Microbiology and Biotechnology Letters
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• v.36 no.4
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• pp.326-335
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• 2008

The siderophore ($siderophore_{AH18}$) of Bacillus subtilis AR18 was determined to be one of catechol type and purified by using Amberlite XAD-2, Sephadex LR-20 chromatography, and reversed-phase RPLC. The $Siderophore_{AH18}$ was identified bacillibactin with its structure by GC-MS, $^1H$-NMR, and $^{13}C$-NMR. $Siderophore_{AH18}$ (bacillibactin) had been confirmed its molecular weight of 883 and chemical structure of $(2,3-dihydroxybenzoate-glycine-threonine)_3$. Purified $siderophore_{AH18}$ showed strong biocontrol ability towards the spore of Phytophthora capsici on PDA and able to effectively suppress (55%) P. capsici causing red-pepper blight in the pot in vivo test.

• Microbiology and Biotechnology Letters
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• v.35 no.4
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• pp.357-363
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• 2007

249 fungal strains were isolated from the roots of 26 plants, and the production of GAs was spectrophotometric ally examined. As a result 76 fungal strains were shown to produce GAs. Bioassay of culture broth from seventy six fungal strains producing GAs was carried out with waito-c rice, that is dwarf rice. The seventy six fungi with GAs-producing activity were incubated for seven days in 40 mL of Czapek's liquid medium at $30^{\circ}C$ and 180 rpm, and the culture broth of fungi were treated on the 2-leaf rice sprout. Fifteen of these showed plant growth promoting activity and the amount of each GAs in the medium was measured by Gas chromatographymass spectrometer (GC-MS). Nine of these fungi were also identified by genetic analysis of the nucleotide sequences in the internal transcribed spacer region of the ribosomal DNA.

• Korean Journal of Soil Science and Fertilizer
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• v.49 no.2
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• pp.144-156
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• 2016

Soil is a dynamic biological system, in which it is difficult to determine the composition of microbial communities. Knowledge of microbial diversity and function in soils are limited because of the taxonomic and methodological limitations associated with studying the organisms. In this review, approaches to measure microbial diversity in soil were discussed. Research on soil microbes can be categorized as structural diversity, functional diversity and genetic diversity studies, and these include cultivation based and cultivation independent methods. Cultivation independent technique to evaluate soil structural diversity include different techniques such as Phospholipid Fatty Acids (PLFA) and Fatty Acid Methyl Ester (FAME) analysis. Carbon source utilization pattern of soil microorganisms by Community Level Physiological Profiling (CLPP), catabolic responses by Substrate Induced Respiration technique (SIR) and soil microbial enzyme activities are discussed. Genetic diversity of soil microorganisms using molecular techniques such as 16S rDNA analysis Denaturing Gradient Gel Electrophoresis (DGGE) / Temperature Gradient Gel Electrophoresis (TGGE), Terminal Restriction Fragment Length Polymorphism (T-RFLP), Single Strand Conformation Polymorphism (SSCP), Restriction Fragment Length Polymorphism (RFLP) / Amplified Ribosomal DNA Restriction Analysis (ARDRA) and Ribosomal Intergenic Spacer Analysis (RISA) are also discussed. The chapter ends with a final conclusion on the advantages and disadvantages of different techniques and advances in molecular techniques to study the soil microbial diversity.

• Korean Journal of Soil Science and Fertilizer
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• v.45 no.5
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• pp.817-821
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• 2012

Soil samples collected from abounded mines of Boryeong area in South Korea were used in isolating bacterial strains and their capacity to solubilize inorganic phosphates and heavy metal tolerance were assessed in vitro. Three different inorganic phosphate sources (Ca phosphate, Fe phosphate, and Al phosphate) and four different heavy metals (Co, Cd, Pb and Zn) each with three concentrations ($100{\mu}g\;mL^{-1}$, $200{\mu}g\;mL^{-1}$, and $400{\mu}g\;mL^{-1}$) were used. The bacterial isolates PSB-1, PSB-2, PSB-3, and PSB-4 solubilized significantly higher amount of Ca phosphate during the first five days of incubation though subsequent drop in soluble phosphorus level in the medium was observed at the later stage (after 5 days) of the incubation. Solubilization of Ca phosphate and Fe phosphate was concomitant with the acidification of the culture medium compared to the control where it remained constant. Isolated strains could solubilize Fe phosphate to certain extent ($25-45{\mu}g\;mL^{-1}$) though solubilization of Al phosphate was found negligible. All the isolates were tolerant to heavy metals (Cd, Pb, and Zn) up to the concentration of $400{\mu}g\;mL^{-1}$ except PSB-1 and PSB-8, which were shown to be vulnerable to Co even at $100{\mu}g\;mL^{-1}$. Heavy metal tolerant strains should be further evaluated for plant growth promoting activities also under field conditions in order to assess their agricultural and environmental significance.

• Korean Journal of Soil Science and Fertilizer
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• v.43 no.4
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• pp.522-527
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• 2010

Gibberellic acid ($CA_3$) is used in many industries and constitutes the primary gibberellins produced by fungi and bacteria. However, there is no information on $CA_3$ production by Methylobacterium oryzae CBMB20, a novel plant growth promoting bacterium. We investigated the favorable carbon (C) and nitrogen (N) sources and ratios and cultural conditions, such as incubation temperature, pH of the culture medium, and incubation period for the maximum production of $CA_3$ by Methylobacterium oryzae CBMB20. Maximum $CA_3$ production was observed in ammonium mineral salt (AMS) broth supplemented with Na-succinate and $NH_4Cl$ as C and N sources, respectively. The maximum $CA_3$ production was found at the C/N ratio of 5:0.4 g $L^{-1}$. The highest $CA_3$ production was obtained when the bacterial culture was incubated at $30^{\circ}C$ for 96 h at pH 7.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.18
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• pp.7527-7532
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• 2014

Saussurea involucrata is a Mongolian medicinal plant well known for its effects in promoting blood circulation, and anti-inflammation and analgesic functions. Earlier studies reported that Saussurea involucrata has anticancer activity. The purpose of this study was to confirm the anticancer activity of an ethanol extract of Saussurea involucrata against hepatic cancer and elucidate its mechanisms of action. Hepatocellular carcinoma cells were tested in vitro for cytotoxicity, AO/EB staining for apoptotic cells, apoptotic DNA fragmentation and cell cycle distribution in response to Saussurea involucrata extract (SIE). The mRNA expression of caspase-3,-9 and Cdk2 and protein expression of caspase-3,-9, PARP, XIAP, Cdk2 and p21 were analyzed through real time PCR and Western blotting. Treatment with SIE inhibited HepG2 cell proliferation dose- and time-dependently, but SIE only exerted a modest cytotoxic effect on a viability of Chang human liver cells. Cells exposed to SIE showed typical hallmarks of apoptotic cell death. Cell cycle analysis revealed that SIE caused G1-phase arrest in HepG2 cells. In conclusion, Saussurea involucrata ethanol extract has potential cytotoxic and apoptotic effects on human hepatocellular carcinoma cells. Its mechanism of action might be associated with the inhibition of DNA synthesis, cell cycle (G1) arrest and apoptosis induction through up-regulation of the protein expressions of caspase-3,-9 a nd p21, degradation of PARP and down-regulation of the protein expression of Cdk2 and XIAP.