• Applied Biological Chemistry
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• v.30 no.4
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• pp.300-304
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• 1987

Effects of benzyladenine (BA) on viability, cell wall regeneration and division of soybean (Glycine max, Var. Acme) protoplasts isolated from suspension cells of cotyledonary callus were investigated. The uptake of BA by the protoplasts was also studied. BA increased protoplast viability, and promoted cell wall regeneration and cell division. The level of BA in protoplasts was increased to a maximum at about 20 hour incubation and 2/3 of the total amount of BA accumulated in protoplast was absorbed within 6 hours.

• Molecules and Cells
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• v.25 no.2
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• pp.294-300
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• 2008

Cytokinins are essential hormones in plant development. $\underline{A}$rabidopsis $\underline{h}$istidine-containing $\underline{p}$hosphotransfer proteins (AHPs) are mediators in a multistep phosphorelay pathway for cytokinin signaling. The exact role of AHP4 has not been elucidated. In this study, we demonstrated young flower-specific expression of AHP4, and compared AHP4-overexpressing (Ox) trangenic Arabidopsis lines and an ahp4 knock-out line. AHP4-Ox plants had reduced fertility due to a lack of secondary cell wall thickening in the anther endothecium and inhibition of IRREGURAR XYLEMs (IRXs) expression in young flowers. Conversely, ahp4 anthers had more lignified anther walls than the wild type, and increased IRXs expression. Our study indicates that AHP4 negatively regulates thickening of the secondary cell wall of the anther endothecium, and provides new insight into the role of cytokinins in formation of secondary cell walls via the action of AHP4.

• Journal of Life Science
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• v.21 no.6
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• pp.865-874
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• 2011

The genus Bryophyllum is best known for many of its species having the ability to produce plantlets on their leaves. This phenomenon is also known as vegetative reproduction. Differential expressed gene (DEG) detecting technique was applied in order to survey the genes involved in the process of asexual reproduction for plantlet formation. Based on homology search using the NCBI database after screening of genes, 38 genes were identified from a total of 69 DEGs. Most of these DEGs were related to cell division, to intercellular signal transduction, and to hormone (cytokinin and ethylene) signaling.

• Korean Journal of Plant Tissue Culture
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• v.26 no.2
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• pp.133-136
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• 1999

Different kinds of cytokinins and auxins were tested for both shoot induction and rooting in a rare species, Abeliophyllum distichum Nakai. BA in WPM medium was the most effective in shoot induction, whereas zeatin seemed to be the most suitable for shoot elongation. Kinetin, at the concentration of 2.0~5.0 mg/L showed an effect in shoot induction, but the effect was inferior to BA and zeatin. Rapid shoot elongation could be achieved when the cultures were maintained on the diffuse light condition (below 500 lux) regardless of cytokinin treatments. For in vitro rooting, IBA was investigated as the best type of auxin tested when half strength GD medium was incorporated. The frequency of rooting using the plant growth regulator and medium just mentioned above was revealed as approximately 90%. In addition, the survival rate of rooted plantlets was almost 100% in an artificial soil mixture.

• Journal of Ginseng Research
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• v.21 no.1
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• pp.13-18
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• 1997

Identification and changes of physiologically active substances during chilling storage of dehisced ginseng (Panax ginseng C. A. Meyer) seeds were analyzed using various preparatory separation methods and purification columns; Dowex 50W and silica gel columns. Seven components with Rf values of 0.20, 0.40, 0.58, 0.66, and 0.70 In solvent system, $CHCl_3$:MeOH=3:1 (v/v), Rf values of 0. 63 and 0.74 in solvent system, $CHCl_3$:MeOH:$H_2O$:=7:3:1 (v/v) were obtained through Dowex 50W and silica gel column chromatographies. Two components with Rf values of 0.20 and 0.63 in the all chilling treatments were detected in the extract obtained through both chromatographies, and only the former component was gradually increased till 4 weeks of chilling storage and then rapidly decreased from 8 to 16 weeks. UV spectra of Rf values of 0.66 and 0.56 were similar to that of cytokinin, but their physiological activities were not found. Rf values of 0.20 showed activity by radish cotyledon expansion bioassay. The component with Rf value of 0.20 was revealed to have a naphthalene in the proposed chemical structure by various NMR techniques.

• Journal of Plant Biology
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• v.39 no.4
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• pp.231-235
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• 1996

The calli obtained from the bulbs of A. victorialis var. platyphyllum on MS based medium containing 2 mg/L 2, 4-D and 1mg/L BA. Plants from calli were regenerated on MS basal media supplemented with combinations of NAA and four kinds of cytokinin, BA, zeatin, kinetin and 2iP, and with only each cytokinin. The good response of shoot regeneration was observed in the media with combinations of NAA and BA or zeatin, and with only BA or zeatin. Shoot regenerating response in the medium with combinations of NAA and BA or zeatin, and with only BA or zeatin. Shoot regerating response in the medium with combinations of NAA and BA or zeatin was about two times higher than that in the mediuim with only BA or zeatin. From the karyotypic analysis of the regenerated plants, abnormal diploids, aneuploids and mixoploid with structural aberrations were investigated. The somaclonal variants (AV 16-04, AV 13-03) were shown the considerable differences from normal diploid regenerant (AV 18-03) in the external morphology.

• Korean Journal of Medicinal Crop Science
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• v.2 no.3
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• pp.219-226
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• 1994

Immature ovule of intergeneric $F_1$ hybrid between Platycodon grandiflorum x Codonopsis lanceolata for producing embryogenic callus. somatic embryos and plant regeneration were cultured in vitro on various medium as well as MT(Murashige Tucker)medium treated with different concentration of plant growth regulators. Embryogenic callus induction was highest in the treatment of NAA 0.5 $mg/{\ell}$ and zeatin 0.01 $mg/{\ell}$ added on MT medium, whereas it was lower in treatments with auxins alone. MT medium were more effective in production of somatic embryos from incubated embryogenic callus. Most favorable plant growgh regulator for producing somatic embryos was 2. 4-D 0.5 $mg/{\ell}$ and zeation. BAP 0.01$mg/{\ell}$, but hormone-free and auxins alone were less effective. NAA 0.01$mg/{\ell}$ added with zeation 0.5 $mg/{\ell}$ was effective as high as NAA 0.01 $mg/{\ell}$ alone in normal plant regeneration from somatic embryo.

• Korean Journal of Plant Tissue Culture
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• v.25 no.1
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• pp.33-36
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• 1998

Guzmania was propagated through in vitro culture of lateral shoots. When new shoots grown in greenhouse were cut and cultured in vitro, contamination rate was very high at about 80% in the first stage of in vitro culture. Among cytokinin treatments for agar medium, 2.0 mg/L BA was most effective for shoot multiplication, and those with 0.5 mg/L kinetin and 0.5~1.0 mg/L BA were favorable for shoot multiplication. BA was more effective for shoot multiplication than kinetin, and shoot multiplication was more enhanced when 2.0 mg/L BA was combined with 0.1~0.5 mg/L IAA than 2.0 mg/L BA alone. The medium with 2.0 mg/L BA and 0.1 mg/L IAA showed the highest rate of shoot multiplication with about 8.7 in shoot number, and those with 2.0 mg/L BA and 0.5~1.0 mg/L IAA also resulted in high multiplication of shoots. Shoots were multiplicated more in liquid rotation culture(80 rpm) with the medium containing 0.5 mg/L BA and 0.1 mg/L IAA than liquid stagnating and solid cultures. Regenerated shoots formed roots very favorably in the medium supplemented with 2.0 mg/L IBA.

• Current Research on Agriculture and Life Sciences
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• v.6
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• pp.75-85
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• 1988

The concentration of 50 mM Nacl inhibited the shoot growth of P. nigra ${\times}$ maximowiczii in viro culture. The punctured leaves have produced so many individuals on MS basal medium with cytokinin. Especially MS basal medium with BAP 0.8mg/l showed the best shoot performance in which the average number of shoots were 127.6. For selection of NaCl tolerance shoot of poplar, punctured leaves were inoculated on MS basal medium with BAP 0.8mg/l and various concentrations of NaCl(from 10 mM to 100 mM graded by 10 mM). On the medium with over 50mM of NaCl, 13.7 to 15.7 shoots were obtained. Especially on the medium with go mM and 100mM. 10.7 and 8.3 shoots, respectively. The shoots derived from control medium (non-NaCl) were depressed growth, while the selected shoots from MS with NaCl showed good growth performance on MS basal medium with 50 mM of NaCl. From this results, we suggested that the possibility of in vitro selection to tolerance for inorganic salts in forest tree species.

• Korean Journal of Plant Resources
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• v.24 no.5
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• pp.483-488
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• 2011

Cacalia firma recently has been used increasingly as leaf vegetables but endangered in natural forest. In this work, we established the plant regeneration via adventitious shoot formation from petiole segments of seedling and in vitro plantlets. Wounding of seed coats and $GA_3$ treatments were effective to induce in vitro germination of seeds, whereas, seed did not germinate at all without these treatment. When cotyledon, leaf, petiole, and root segments of seedling were cultured on medium with 2 $mg{\cdot}L^{-1}$ benzyl adenine (BA) and 0.5 $mg{\cdot}L^{-1}$ naphthaleneacetic acid (NAA), petiole segments showed highest number of shoots per explant among the other segments. Among the various kinds of cytokinins, BA, isopentyl adenine (2-ip), kinetin, zeatin, thidiazuron (TDZ), TDZ and BA treatments were effective to induce high frequency of adventitious shoot formation from petiole segments of in vitro propagated plants. NAA stimulated the frequency of adventitious shoot formation but not for number of adventitious shoots per explants compared to TDZ or BA treatment alone. Most of adventitious shoots were developed directly from surfaces of explants. Adventitious shoots were transferred on medium with IBA for root formation, thereafter the plantlets were successfully transferred to soil.