• Journal of Ginseng Research
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• v.24 no.4
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• pp.157-161
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• 2000

Cell growth and production of phenolic compounds by callus cultures of Panax ginseng C. A. Meyer were investigated under various phytohormones concentrations and inoculum size. The results indicated that the cell growt was improved by a MS medium supplemented with 2 mg/L of CPA. The maximum cell yield was obtained at inoculum size of 1 g/flasd. The production of phenolic compounds in the callus cultures was higher than those in the ginseng root. Especially, one cell line (20601) showed the highest content of phenolic compounds and antioxidant activity.

• The Journal of Natural Sciences
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• v.10 no.1
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• pp.33-37
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• 1998

Cytokinin is one of major growth regulators in plants. In this study, the gene isopentenyl transferase (jpt) which encodes a key enzyme involved in the biosynthesis of the growth regulator cytokinin isolated from Agrobacterium tumefaciens was introduced ito tobacco plant via Agrobacterium-mediated transformation. The jpt gene was modulated using the proteinase inhibitor II (PI-IIK) promotor. In general, this promoterlipt gene fusion resulted in overproduction of cytokinins throughout the transgenic plants. The overproduction of cytokinin caused dramatic changes in morphology of the plant, including stem thickness and reduced root development. The studies reported in this paper were initiated to examine the consequences of overproduction of cytokinin in plant.

• Journal of Microbiology
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• v.41 no.4
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• pp.271-276
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• 2003

The inoculation of some microorganisms into a microcosm containing soil from a barren lakeside area at Lake Paro in Kangwon-do enhanced plant growth significantly. The direct and viable counts of soil bacteria and soil microbial activities measured by electron transport system assay and fluorescein diacetate hydrolysis assay were higher in inoculated soil. The plant growth promoting effect of this inoculation may be caused by phytohormone production and the solubilization of insoluble phosphates by the inoculated bacteria. Three inoculated strains of Pseudomonas fluorescens produced several plant growth promoting phytohormones, including indole-3-acetic acid (auxin), which was confirmed by thin layer chromatography and GC/MS. P. fluorescens strain B16 and M45 produced 502.4 and 206.1 mg/l of soluble phosphate from Ca3(PO4)2 and hydroxyapatite, respectively. Bacillus megaterium showed similar solubilization rates of insoluble phosphates to those of Pseudomonas spp. We believe that this plant growth promoting capability may be used for the rapid revegetation of barren or disturbed land.

• Journal of Plant Biotechnology
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• v.46 no.3
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• pp.143-157
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• 2019

Medicinal plants are high-value natural resources that have been used as precautionary drugs by many people globally. The increasing global demand for bioactive compounds from medicinal plants has led to the overexploitation of many valuable species. One widely used approach to overcome this problem is the use of adventitious root cultures as a propagation strategy. This review examines the scientific research published globally on the application of adventitious root cultures for many medicinal plants. Adventitious roots generated under aseptic environments in suitable phytohormone-augmented medium exhibit high growth rates and production of important secondary metabolites. Parameters such as medium properties and composition, growth hormone type, and elicitation strategies for in vitro grown adventitious roots of medicinal plants, are the main topics discussed in this review. We also examine current developments in bioreactor system cultivation for plant bioactive compounds using adventitious root cultures, a technology with possible commercial applications, via several studies on adventitious root culture of medicinal plants in which bioreactor systems play a role. In conclusion, the development of adventitious root cultures for medicinal plants is highly useful because of their capability for vegetative propagation and germplasm preservation.

• Plant Resources
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• v.1 no.2
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• pp.98-104
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• 1998

The effects of basal media, sucrose and phytohormone concentrations, and gelling agent combinations on in vitro frond proliferation of Lemna gibba G3 and 24 additional Lemna gibba strains were examined. Frond proliferation was equivalent on Schenk and Hidebrand. Murashige and Skoog. Nitsch and Nitsch, and Gamborg's B5 media and poor on murashige and Skoog medium in the absence of benzyladenine. With the addition of benzyladenine, Schenk and Hildebrand and Gamborg's B5 Were superior and equivalent. The addition of benzuyladenine increased equally frond proliferation at either 1 or $10{\mu}M$, however at $10{\mu}M$ fronds were severely curled or fused. Benzyladenine and thidiazuron suppressed root growth but kinetin was found to greatly enhance root growth. Gibberellic acid inhibited frond proliferation. Frond proliferation was significantly different on the four sucrose concentrations of 0, 1, 3, and 5% Among them, 3% sucrose was found to be superior. The reduced frond size observed in cultures grown on 8% sucrose could be explained by showing medium osmotic potential in excess of frond water potential. Gell agents also varied significantly in their ability to promote frond proliferation with 0.25% Gelrite or a mixture of 0.15% Gelrite and 0.4% agar. Proliferation of 25 Lemna gibba strains on medium neat optimal for Lemna gibba G3 showed a six-fold variation across strains with Lemna gobba G3 placing in the top 5 fastest proliferating strains.

• Korean Journal of Agricultural Science
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• v.50 no.4
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• pp.759-771
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• 2023

Plant growth-promoting rhizobacteria (PGPR) are naturally occurring bacteria that intensively colonize plant roots and are crucial in promoting the crop growth. These beneficial microorganisms have garnered considerable attention as potential bio-inoculants for sustainable agriculture. PGPR directly interacts with plants by providing essential nutrients through nitrogen fixation and phosphate solubilization and accelerating the accessibility of other trace elements such as Cu, Zn, and Fe. Additionally, they produce plant growth-promoting phytohormones, such as indole acetic acids (IAA), indole butyric acids (IBA), gibberellins, and cytokinins.PGPR interacts with plants indirectly by protecting them from diseases and infections by producing antibiotics, siderophores, hydrogen cyanide, and fungal cell wall-degrading enzymes such as glucanases, chitinases, and proteases. Furthermore, PGPR protects plants against abiotic stresses such as drought and salinity by producing 1-aminocyclopropane-1-carboxylic acid (ACC) deaminase and modulating plant stress markers. Bacteria belonging to genera such as Bacillus, Pseudomonas, Burkholderia, Pantoa, and Enterobacter exhibit multiple plant growth-promoting traits, that can enhance plant growth directly, indirectly, or through synergetic effects. This comprehensive review emphasizes how PGPR influences plant growth promotion and presents promising prospects for its application in sustainable agriculture.

• 한국생물공학회:학술대회논문집
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• 2001.11a
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• pp.681-684
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• 2001

Pseudomonas sp. F721 isolated from soil produced a substance related in seeds germination inhibition. Addition of phytohormone, and GA (gibberellin acid) in the culture broth elevated production of the germination inhibition substance. The production of the substance was optimized in the culture conditions of $35^{\circ}C$, pH 9.0, 150 rpm, 48 hr, glucose 0.5% (w/v), and innoculation ratio 1.0% (v/v). The physical and chemical stability of the substance in the variety of pH ranging from 2.0 to 12.0 and from freezing to $100^{\circ}C$ were shown. The germination inhibition substance suppressed 90% of germination compared with that of the control experiment in a few days.

• Korean Journal of Plant Tissue Culture
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• v.21 no.6
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• pp.341-345
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• 1994

The effect of phytohormones on in vitro production of ubiquinone 10 from the callus cultures of Nicotiana tabacum cv Xanthi was investigated. The growth of callus cultures of Xanthi was in proved by addition of NAA and 2,4-D, especially NAA 0.5 mg/L alone, at the light condition. Ubiquinone 10 was detected by HPLC, and confirmed from Xanthi callus cultured on the all of uppermedia. The ubiquinone 10 content in Xanthi tobacco callus cultured on the medium with NAA 0.5 mg/L only was higher than that of other mixed medium with NAA and 2,4-D. However addition of IBA 1 mg/L and NAA 0.5 mg/L to the medium was more effective in promoting ubiquinone 10 formation than that of NAA 0.5 mg/L only As the callus growth of Xanthi was considerabley restrained at concentration of kinetin, Content and production of ubiquinone low as the highest at kinetin 0.5mg/L and 2,4-D 0.5mg/L in the light.

• The Plant Pathology Journal
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• v.34 no.3
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• pp.208-217
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• 2018

In this study, samples were collected from the leaves and stems of healthy wild Pistachio trees (Pistacia atlantica L.) from various locations of Baneh and Marivan regions, Iran. In total, 61 endophytic bacteria were isolated and grouped according to phenotypic properties. Ten selected isolates from each group were further identified by partial sequencing of the 16S rRNA gene. Based on the results, isolates were identified as bacteria belonging to Pseudomonas, Stenotrophomonas, Bacillus, Pantoea and Serratia genus. The ability of these isolates was evaluated to phytohormone production such as auxin and gibberellin, siderophore production, phosphate solubilization, atmospheric nitrogen fixation, protease and hydrogen cyanide production. All strains were able to produce the plant growth hormone auxin and gibberellin in different amounts. The majority of strains were able to solubilize phosphate. The results of atmospheric nitrogen fixation ability, protease and siderophore production were varied among strains. Only Ba66 could produce a low amount of hydrogen cyanide. The results of biocontrol assay showed that Pb78 and Sp15 strains had the highest and lowest inhibition effects on bacterial plant pathogens, Pseudomonas syringae pv. syringae Pss20 and Pseudomonas tolaasii Pt18 under in vitro condition. Pb3, Pb24 and Pb71 strains significantly promote root formation on carrot slices. To our knowledge this is the first report of the isolation of endophytic bacterial strains belonging to Pantoea, Bacillus, Pseudomonas, Serratia and Stenotrophomonas genus from wild pistachio trees with plant growth promoting potential and biocontrol activity.

• Korean Journal of Plant Tissue Culture
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• v.25 no.6
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• pp.525-530
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• 1998

These studies were carried out to select the active grow hairy root lines induced from various ginseng(Panax ginseng C. A. Meyer) parts. Hairy roots were induced in root explants, stem and petiole in vitro by A. rhizogenes R1000 or A. rhizogenes $A_4$. These hairy roots could be grown on the phytohormone free medium, and PCR analysis of rol C and vir C gene fragments confirmed that hairy roots were transgenic tissues. We have selected 11 hairy root lines with active growing characters among 300 hairy root lines selected based on growth and morphological characteristics on 1/2MS solid media with 250 mg/L carbenicillin. Morphological characteristics of selected 11 hairy root lines were thickness and thiness of main roots, and many projection for lateral roots, active grow of lateral roots. Among selected 11 hair root lines prominent characteristics of hairy roots with active growing characters were thiness of main roots and active grow of lateral roots. But characteristics of low growing hairy roots were thickness of main roots and low grow of lateral roots. Finally we have selected actively growing hairy roots, KGHR-1, KGHR-5, KGHR-8 among 11 hairy root lines.