• The Plant Pathology Journal
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• v.20 no.1
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• pp.63-66
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• 2004

Ginseng (Panax ginseng) is one of the most widely cultivated medicinal herbs in Korea. However, yield losses reached up to 30-60％ due to various diseases during 3 or 5 years of ginseng cultivation in the country. Therefore, successful production of ginseng roots depends primarily on the control of diseases. The objective of this study was to select potential biocontrol agents from rhizobacteria isolated from various plant internal root tissues for the control of multiple ginseng diseases as an alternative to fungicides. Among 106 Bacillus strains, two promising biocontrol agents, Bacillus pumilus strain B1141 and Paenibacillus lentimobus strain B1146, were selected by screening against root rot of ginseng caused by Cylindrocarpon destructans in a greenhouse. Pre-inoculation of selected isolates to seed or l-year-old root of ginseng resulted in stimulation of shoot and/or root growth of seedlings, and successfully controlled root rot caused by C. destructans (P<0.05). Furthermore, drenching of cell suspension of the selected isolates on seedling-growing pots reduced the incidence of Phytophthora blight after the seedlings were challenged with zoospores of Phytophthora cactorum (P<0.05). P. lentimorbus strain B1146 showed antifungal activity against various soil-borne pathogens in vitro, while B. pumilus strain B1141 did not show any. Results of this study suggest that some rhizobacteria can induce resistance against various plant diseases on ginseng.

• The Plant Pathology Journal
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• v.32 no.6
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• pp.552-562
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• 2016

Pathogenesis-related proteins play multiple roles in plant development and biotic and abiotic stress tolerance. Here, we characterize a rice defense related gene named "jasmonic acid inducible pathogenesis-related class 10" (JIOsPR10) to gain an insight into its functional properties. Semi-quantitative RT-PCR analysis showed up-regulation of JIOsPR10 under salt and drought stress conditions. Constitutive over-expression JIOsPR10 in rice promoted shoot and root development in transgenic plants, however, their productivity was unaltered. Further experiments exhibited that the transgenic plants showed reduced susceptibility to rice blast fungus, and enhanced salt and drought stress tolerance as compared to the wild type. A comparative proteomic profiling of wild type and transgenic plants showed that overexpression of JIOsPR10 led to the differential modulation of several proteins mainly related with oxidative stresses, carbohydrate metabolism, and plant defense. Taken together, our findings suggest that JIOsPR10 plays important roles in biotic and abiotic stresses tolerance probably by activation of stress related proteins.

• Korean Journal of Plant Resources
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• v.17 no.2
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• pp.153-160
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• 2004

Glehnia littoralis is known as an edible and medicinal plant using green loaves and mature roots of plant. In the present paper, the influence of plant growth regulators on callus induction and plant regeneration was investigated. Callus induction and regeneration occurred from leaf and petiole explants in Glehnia littoralis. Optimal condition of plant growth regulators for callus induction from leaf and petiole explants was MS basal medium supplemented with 2mg/L 2,4-D and 2mg/L BA. The frequency of callus induction was higher in petiole explant than leaf. When the callus was cultured on MS basal medium supplemented with 0∼1 mg/L IAA, 0∼1mg/L NAA and 0∼2mg/L BA for about 65 days, the most effective plant growth regulators on plant regeneration from callus were 1mg/L NAA and 2mg/L BA. The plantlets acclimatized successfully and grown in vermiculite matrix.

• Journal of Microbiology and Biotechnology
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• v.31 no.8
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• pp.1045-1059
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• 2021

Various abiotic stressors like drought, salinity, temperature, and heavy metals are major environmental stresses that affect agricultural productivity and crop yields all over the world. Continuous changes in climatic conditions put selective pressure on the microbial ecosystem to produce exopolysaccharides. Apart from soil aggregation, exopolysaccharide (EPS) production also helps in increasing water permeability, nutrient uptake by roots, soil stability, soil fertility, plant biomass, chlorophyll content, root and shoot length, and surface area of leaves while also helping maintain metabolic and physiological activities during drought stress. EPS-producing microbes can impart salt tolerance to plants by binding to sodium ions in the soil and preventing these ions from reaching the stem, thereby decreasing sodium absorption from the soil and increasing nutrient uptake by the roots. Biofilm formation in high-salinity soils increases cell viability, enhances soil fertility, and promotes plant growth and development. The third environmental stressor is presence of heavy metals in the soil due to improper industrial waste disposal practices that are toxic for plants. EPS production by soil bacteria can result in the biomineralization of metal ions, thereby imparting metal stress tolerance to plants. Finally, high temperatures can also affect agricultural productivity by decreasing plant metabolism, seedling growth, and seed germination. The present review discusses the role of exopolysaccharide-producing plant growth-promoting bacteria in modulating plant growth and development in plants and alleviating extreme abiotic stress condition. The review suggests exploring the potential of EPS-producing bacteria for multiple abiotic stress management strategies.

• Analytical Science and Technology
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• v.31 no.4
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• pp.161-170
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• 2018

The epidemic of disorders associated with synthetic stimulants, such as methamphetamine (MA) and amphetamine (AP), is a health, social, legal, and financial problem. Owing to the high potential of their abuse and addiction, reliable analytical methods are required to detect and identify MA, AP, and their metabolites in biological samples. Thus, a dilute-and-shoot liquid chromatography-tandem mass spectrophotometry (LC-MS/MS) was developed for simultaneous determination of MA, 4-hydroxymethamphetamine (4HMA), AP, and 4-hydroxyamphetamine (4HA) in urine. Urine sample ($100{\mu}L$) was mixed with $50{\mu}L$ of mobile phase consisting of 0.4 % formic acid and methanol and $50{\mu}L$ of working internal-standard solution. Aliquots of $8{\mu}L$ diluted urine was injected into the LC-MS/MS system. For all analytes, chromatographic separation was performed using a C18 reversed-phase column with gradient elution and a total run time of 5 min. The identification and quantification were performed by multiple reaction monitoring (MRM). Linear least-squares regression was conducted to generate a calibration curve, with $1/x^2$ as the weighting factor. The linear ranges were 2.0-200, 1.0-800, and 10-2500 ng/mL for 4HA and 4HMA, AP, and MA, respectively. The inter- and intraday precisions were within 6.6 %, whereas the inter- and intraday accuracies ranged from -14.9 to 11.3 %. The low limits of quantification were 2.0 ng/mL (4HA and 4HMA), 1.0 ng/mL (AP), and 10 ng/mL (MA). The proposed method exhibited satisfactory selectivity, dilution integrity, matrix effect, and stability, which are required for validation. Moreover, the purification efficiency of high-speed centrifugation was clearly higher than 6-15 % for QC samples (n=5), which was higher than that of the membrane-filtration method. The applicability of the proposed method was tested by forensic analysis of urine samples from drug abusers.

• Journal of the Korea Society for Simulation
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• v.29 no.1
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• pp.47-55
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• 2020

This paper presents a real-time autonomous computation of shot numbers and aiming points against multiple soft targets on grounds by applying an unsupervised learning, k-mean clustering and Monte carlo simulation. For this computation, a 100 × 200 square meters size of virtual battlefield is created where an augmented enemy infantry platoon unit attacks, defences, and is scatted, and a virtual weapon with a lethal range of 15m is modeled. In order to determine damage types of the enemy unit: no damage, light wound, heavy wound and death, Monte carlo simulation is performed to apply the Carlton damage function for the damage effect of the soft targets. In addition, in order to achieve the damage effectiveness of the enemy units in line with the commander's intention, the optimal shot numbers and aiming point locations are calculated in less than 0.4 seconds by applying the k-mean clustering and repetitive Monte carlo simulation. It is hoped that this study will help to develop a system that reduces the decision time for 'detection-decision-shoot' process in battalion-scaled combat units operating Dronebot combat system.

• Journal of Korean Society of Forest Science
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• v.66 no.1
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• pp.1-7
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• 1984

This study was undertaken to find out the effects of three kinds of potting media and two sources of explants on the survival and early growth of new plantlets of Poputus alba ${\times}$ P. grandidentata in the greenhouse. The results obtained can be summarized as follows; 1) Among three potting media, Terralite was best for early growth and survival of plantlets. 2) Like humidifier, an intermittent misting system can be effective in keeping relative humidity high for the plantlets. 3) Survival rates over 80% could be obtained if humidity was kept high during the hardening period. 4) During hardening period, the plantlets showed the juvenile characteristics such as smaller leaves, thinner stems, and shorter internodes. 5) There were no differences on morphological characteristics between the plantlets originating from axillary buds and the plantlets originating from multiple shoots while they were growing at the greenhouse. 6) The plantlets originating from bud culture grew normally comparing to regular cuttings.

• Current Research on Agriculture and Life Sciences
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• v.3
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• pp.1-7
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• 1985

The study was conducted in order to get basic information on seed germination and seedling growth through the experiments such as basal medium, concns of auxin, sucrose agar and pH values. Seed germination was very excellent in $3g/{\ell}$ hyponex and $5g/{\ell}$ peptone containing medium. Multiple shoots were formed in $1-3g/{\ell}$ hyponex and $5g/{\ell}$ pepton containg medium supplemented with $1.0g/{\ell}$ IBA, $30g/{\ell}$ sucrose and $8g/{\ell}$ agar. Growth of seedlings was more stimulated in the same amount of hyponex and peptone as above medium substituted with $40g/{\ell}$ sucrose and $6g/{\ell}$ agar without IBA.

• Journal of Plant Biotechnology
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• v.34 no.2
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• pp.139-144
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• 2007

Hypocotyl explants of Chinese cabbage (cvs. "Jeong Sang") produced transgenic calli on callus induction medium (MS salt, B5 vitamin, 5 mg/L acetosyringone, 1 mg/L 2,4-D, 3% sucrose, 400 mg/L cefotaxime, 100 mg/L paromomycin, pH 5.8) after cocultivation with strains of Agrobacterium tumefaciens (EHA101, LBA4404, GV3101) harboring the pPTN290 containing paromomycin-resistance gene as a selectable marker, and then they transferred to root induction medium (1/2MS salt, MS vitamins, 2% sucrose, 100 mg/L paromomycin, 100 mg/L cefotaxime, pH 5.8) and shoot induction medium (MS salt, B5 vitamin, 4 mg/L $AgNO_3$, 4 mg/L 6-benzyladenine, 3 mg/L alpha-naphthaleneacetic acid, 100 mg/L paromomycin, 100 mg/L cefotaxime, 3% sucrose, pH 5.8) in order. There was a significant difference in the frequency of transgenic calli depending on Agrobacterium strains. In particular, the highest frequency (6.1%) of transgenic calli was obtained from the hypocotyls cocultivated with EHA101 strains. Also, the frequency (%) of transgenic root and plants from each transgenic callus clone were obtained with 60.7% and 38.2% in EHA101, with 8.3% and 0% in LBA4404, with 20.5% and 85.7% in GV3101 strains, respectively. They were grown to maturity in a greenhouse and normally produced $T_2$ seeds. GUS histochemical assay for progeny ($T_2$) revealed that the transgenes was expressed in the plant genome, and progeny analysis from 7 independent transgenic events demonstrated that the transformants transmitted the transgene as a single or multiple functional locus.

• Journal of Plant Biotechnology
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• v.29 no.1
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• pp.45-49
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• 2002

The leaf and petiole segments of Farfugium japonica were cultured to investigate the influence of growth regulators on their callus induction and plant regeneration. The callus induction and growth showed a good response both leaf and petiole on MS media supplemented with 1∼2 mg/L 2,4-D and 1∼2 mg/L BA. Callus induction and growth were more effective in petiole segments than leaf one. The highest percentage of plant regeneration was obtained from 60-day-old calli on MS medium supplemented with 1 mg/L NAA and 2 mg/L BA. When subcultured to the same medium for about 60 days, multiple shoots were developed from regenerating callus. The shoots produced roots after transferring to rooting medium containing 0.5 mg/L IAA. The plantlets over 50 mm in height were successfully acclimatized in vermiculite, and the survival rate was over 95%.