• Journal of Ginseng Research
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• v.5 no.1
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• pp.35-40
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• 1981

Explants of mature root tissues and calli derived from root and cotyledon of Panax ginseng were cultured in vitro on Murashige and Skoog medium supplemented with 2, 4-dichlorophen-oxyacetic acid(3,4-D), naphthaleneacetic acid(NAA), benzyladenine, and gibberellic acid to assess their capacity to regenerate organs. Root formation at high percentage (46.2-61.1%) was obtained 20-30 days after culturing on media supplemented with combinations of NAA(5 mg/l) and kinetin (1 mg/l), And calli derived from cotyledon produced numerous embryoids in media($\frac{1}{2}$MS) containing 2,4-D(0.5 mg/l) and kinetin (0.5 mg/l). Reculture of these embryoids in media($\frac{1}{2}$MS) enriched with 1 mg/l of benzyladenine and 1 mg/l of gibberellic acid resulted in more plantlet regeneration.

• KSBB Journal
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• v.6 no.1
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• pp.27-33
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• 1991

Hairy root induced by A. rhizogenes from potato tuber (Solanm tuberosum L.) synthesized the agropine and mannopine which were demonstrated with paper electrophoresis. And the starch contents in hairy root were increased gradually following the developmental stage. But protein contents were decreased. The activity of ${\beta}-glucan$ synthetase II(GSII) which is related to the cell wall biosynthesis was stimulated in hairy root on the developmental stage. And chloropromazine did not influence the activity of GS II while verapamil inhibited about 60% of the activity GS II. Therefore, these results showed $Ca^{2+}$ to be effective factor in the cell wall formation. Isozyme pattern of peroxidase was investigated in the callus and hairy root induced from potato tuber.

• The Plant Pathology Journal
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• v.29 no.1
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• pp.59-66
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• 2013

Colonization studies previously performed with a green-fluorescent-protein, GFP, labeled derivative of Bacillus amyloliquefaciens FZB42 revealed that the bacterium behaved different in colonizing surfaces of plant roots of different species (Fan et al., 2012). In order to extend these studies and to elucidate which genes are crucial for root colonization, we applied targeted mutant strains to Arabidopsis seedlings. The fates of root colonization in mutant strains impaired in synthesis of alternative sigma factors, non-ribosomal synthesis of lipopeptides and polyketides, biofilm formation, swarming motility, and plant growth promoting activity were analyzed by confocal laser scanning microscopy. Whilst the wild-type strain heavily colonized surfaces of root tips and lateral roots, the mutant strains were impaired in their ability to colonize root tips and most of them were unable to colonize lateral roots. Ability to colonize plant roots is not only dependent on the ability to form biofilms or swarming motility. Six mutants, deficient in abrB-, sigH-, sigD-, nrfA-, yusV and RBAM017410, but not affected in biofilm formation, displayed significantly reduced root colonization. The nrfA- and yusV-mutant strains colonized border cells and, partly, root surfaces but did not colonize root tips or lateral roots.

• Restorative Dentistry and Endodontics
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• v.45 no.3
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• pp.29.1-29.9
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• 2020

This study describes the clinical steps taken in the treatment of a patient who had an avulsed right upper central incisor that presented with incomplete root development and chronic apical periodontitis. A 7-year-old boy was referred from a private dentist to a dental office specializing in endodontics. The tooth had remained in a dry environment for 20 minutes, and tooth replantation was performed at an emergency appointment. After clinical and radiographic examinations, root canal decontamination was performed, followed by several changes in intracanal calcium hydroxide medication. Blood clot formation was attempted, but bleeding within the root canal was insufficient; therefore, we opted for an intracanal medication change to stimulate mineralized tissue formation in the apical region. Root obturation was performed 45 days after the last change of intracanal medication, and clinical, radiographic, and tomographic follow-up examinations were performed at 3, 6, 18, and 40 months after the endodontic intervention. The increase in thickness and length of the root structure and the absence of root resorption were verified through follow-up examinations. Therefore, it was concluded that the procedures used were successful for tooth replantation.

• Korean Journal of Plant Resources
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• v.35 no.6
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• pp.770-777
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• 2022

The main objective of this study was to identify the most appropriate condition for root formation of in vitro micropropagated pear (Pyrus spp.) plants. In vitro propagation was induced on Murashige and Skoog (MS) medium with 2.0 mg/L of N6-benzyladenine (BA) and 0.2 mg/L of Indole-3-butyric acid (IBA) medium. The short pre-treatment of explants with a high concentration (1 mg/L) of NAA and IBA (R0 medium) in dark for three days, followed by transfer to five different media (R1 to R5) resulted in good rooting responses in the pear 'Oharabani (P. pyrifolia × P. communis)' genotype. For the rooting experiments, the highest rooting percentage (83.3 ± 8.3%), average root length (3.6 ± 1.9 mm), total root number (31 ± 4.0), and average root number per plant (2.6 ± 2.1) were obtained on half strength (1/2) of MS medium supplemented with 30 g/L sucrose without hormones and activated charcoal (AC) (R1 medium). The highest rooting percentage was obtained at 83.3% from explants on R1 and R3 media. The rooting procedure described in this study resulted in good root formation and significantly shorting the root induction time to within 14 days of culture. Further studies are underway to test the suitability of the protocol developed in this study for other pear genotypes.

• Korean Journal of Agricultural Science
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• v.5 no.1
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• pp.1-5
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• 1978

Aseptic meristem of Fragaria ananassa 'Hokowase' were inoculated on Murashige and Skoog medium containing various levels of Benzylamiro purine(BA), IAA, and 2.4-D. Formations of shoots plantlets, roots and callus depend on hormone levels used. On medium containing high level of BA 1.0mg/l, multiple plantlets were formed, however, elongation of shoots was inhibited than on BA 0.5 mg/l. 1.0mg/l IAA induced root formation and 1.0mg/l+1.0mg/l BA inhibited root formation. Callus formation was occurred on the medium added 2.4-D. When plantlets were subcultured, formation of callus or shoot depend on BA/2.4-D ratio. 2.0mg/l 2.4-D+0.2mg/l BA and 0.5 mg/l 2.4-D+0.2mg/l BA induced callus formation and 2.0mg/l BA induced plantlet and shoot vigorously.

• Proceedings of the Korean Society of Crop Science Conference
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• 2022.10a
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• pp.161-161
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• 2022

This study aimed to investigate the effect of growth regulators on the formation of the organ in the in vitro propagation of diploid and tetraploid Codonopsis lanceolata, and gain the basic data for in vitro propagation of superior C. lanceolata. In the case of diploid C. lanceolata, the highestshoot formation (3.0) was observed at 0.5 mg·L^-1 addition medium with low IBA concentration. The shoot formation of tetraploid C. lanceolata was suppressed by addition of IBA. In the addition of lAA, the shoot formation of diploid C. lanceolata was slightly higher at 1.0 mg·-L^-1 addition medium than that of control group, whereas tetraploid C. lanceolata showed the highest number (5.4) from control group. In the case of NAA, the shoot formation of diploid and tetra C. lanceolata tended to decrease at higher concentration. In terms of BA addition, the shoot formation of diploid C. lanceolata was increased by the addition of BA, whereaswhile the growth of shoot was decreased by the addition of BA. In the case of tetraploid C. lanceolata, shoot was found to be formed by the addition of low concentration of BA, and the growth of shoot was inhibited with the higher addition concentration of BA. With the addition of kinetin, the shoot formation of diploid C. lanceolata was slightly higher than that of control group, and the formation of adventitious root was highest (5.3) in the control group. In the case of tetraploid C. lanceolata, the shoot formation was similar in all treatment groups, but the formation and growth of adventitious root were significantly lower than that of diploid C. lanceolata. In the case of TDZ addition, the shoot formation of diploid C. lanceolata showed the pronounced results at 5.0 mg·L^-1 addition medium, and the growth of shoot was inhibited by the addition of TDZ. The formation of adventitious root was 5.3 and 4.9 in the control group and 0.1 mg·L^-1 addition medium respectively. The formation of the shoot of tetraploid C. lanceolata showed better results with the higher concentration of TDZ, and the growth was better with the lower concentration of TDZ. The formation and growth of adventitious root were significantly slower than that of diploid C. lanceolata.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.36 no.4
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• pp.287-293
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• 1991

The root-mat formation of infant rice seedlings (8- to 10-day-old) is sometime not enough for machine transplanting because of the too-short nursery period. This experiment was conducted to elucidate the effect of metalaxyl seed-soaking treatment in the mixed solution of metalaxyl, seed disinfectant and insectcides on the root-mat formation of infant rice seedling in machine transplanting. The rice seeds of Odaebyeo were soaked in the mixed solution of metalaxyl, prochloraz and insectcides. with the recommended concentrations for 24 hours at room temperature. Seeding rate was 220g per seed tray (30 x 60 x 3cm). Metalaxyl (25% wettable powder), a fungicide. was used in 1. 000 times dilution as a promoting substance on the root-mat formation. Generally, the metalaxyl-treated seeds markedly increased the root number and length, and rooting activity of infant rice seedlings as compared with the control, thus the root-mat formation was excellent. When the rice seeds were sterilized by the mixed solution of prochloraz and insectcides, metalaxyl could be used together for increasing root-mat rormation of infant rice seedlIngs due to no interaction among agro-chemicals used. Seedling damping-off and physiological seedling rot were also controled in the seedlings of metalaxy-treated seeds. The root-mat of metalxyl-treated seeds had higher hardness and tension than control in terms of physical properties.

• Korean Journal of Plant Resources
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• v.24 no.5
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• pp.514-520
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• 2011

This study describes conditions for the mass production of mutant hairy root lines by co-cultivation with A. rhizogenes harboring the activation tagging vector pHC7. Various sources of explants were subjected to genetic transformation with A. rhizogenes to determine optimum conditions and cultivar for the highest frequency of hairy root formation on explants. Hairy root formation also were investigated in transformed hairy roots grown in various culture media. Finally, a total of approximately 2,500 lines of hairy root mutants were produced in this study. A managing system for metabolomics in hairy root lines also were established. These hairy root lines will be useful to determine functions of genes relating biosynthesis pathway of secondary metabolites.

• Journal of Life Science
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• v.25 no.1
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• pp.37-43
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• 2015

We have investigated the effects of the ethylene precursor 1-aminocyclopropane-1-carboxylic acid (ACC), indole-3-acetic acid (IAA) and methyl jasmonate (MeJA) on the development of aerenchyma in the primary root of maize (Zea mays). Because plant hormones affected the longitudinal organization of the primary root, we need an indicator to direct the positions for comparison between control and hormone-treated roots. Therefore, the zones of the maize primary root were categorized as PR25, PR50 and PR75, where each value indicates the relative position between the root tip (PR0) and the base (PR100). Aerenchyma was not observed at PR25 and PR50 and rarely found at PR75 in the cortex of control roots. The aerenchymal area at PR75 increased in the presence of the ethylene precursor ACC or a natural auxin IAA. On the other hand, MeJA differentially acted on non-submerged and submerged roots. Exogenously applied MeJA suppressed the aerenchyma formation in non-submerged roots. When the primary root was submerged, aerenchymal area expanded prominently. The submergence-induced aerenchyma formation was amplified with MeJA. Lateral root primordia have been known to inhibit aerenchymal death of surrounding cells. All the three hormones stimulating aerenchyma formation as described above did not restore the inhibition caused by lateral root primordia, suggesting that the inhibitory step regulated by lateral root primordia can be located after hormonal signaling steps.