• Korean Journal of Plant Tissue Culture
• /
• v.27 no.1
• /
• pp.39-45
• /
• 2000

Two maize transposable elements, immobilized Ac (iAc) and Ds, have been introduced into the genome of a diploid potato clone (Solanum tuberosum Group Phureja clone 1.22). The iAc is a modified Ac that is supposed to be unable to transpose but is expected to trans-activate the transposition of a Ds that is unable to transpose by itself. When the leaf and stem explants of in vitro shoots of the clone 1.22 were inoculated with Agrobacterium tumefaciens strains harboring binary vectors containing the iAc and the Ds, calli were formed from the explants on media containing 50 mg/L of kanamycin, and shoots were regenerated from the calli. The regenerated shoots formed roots when cultured on media containing 100 mg/L of kanamycin, whereas untransformed shoots did not form roots on the same media. The PCR amplification of the DNA's from the transgenic plants confirmed that the iAc and the Ds elements were introduced into the potato genome of 1.22.

• Korean Journal of Plant Tissue Culture
• /
• v.28 no.1
• /
• pp.21-24
• /
• 2001

Peucedanum japonicum $T_{HUNB}$ used as a edible and medicinal plants was investigated for in uitro regeneration. Callus formation occurred on leaf and stem explant cultures and showed spontaneous embryogenic and organogenic capability on MS basal medium supplemented with 0.1~5 mg/L NAA and 0~10 mg/L BA in dark. The regeneration was highest on the condition supplemented with 2.5 mg/L NAA and 10 mg/L BA. Development of the somatic embryo progressed through the globular, heart-shaped, torpedo-shaped and cotyledonary stage, typical of zygotic embryos. When the first somatic embryos was cultured on the medium supplemented with 0.2 mg/L NAA, secondary somatic embryo were induced with higher frequency on the hypocotyl then on the cotyledon and root.t.

• Korean Journal of Plant Tissue Culture
• /
• v.28 no.3
• /
• pp.123-128
• /
• 2001

In order to develop the biotechnological methods for the mass production of anticancer compounds from tissue culture of Panax ginseng C.A. Mayer, these studies were carried out for the selection of ginseng cell lines containing higher concentration of polyacetylene compounds and optimal condition for their biosynthesis. Panaxynol, one of ginseng polyacetylene, was not detected in any callus induced from ginseng superior cell lines cultured on MS medium supplemented with $\beta$-chlorophenoxy acetic acid (CPA). Panaxydol, another one of polyacetylene and anticancer compounds, were detected in calli of 5 cell lines by thin layer chromatogram and gas chromatogram. Among the 18 ginseng superior lines, the cell line 30201 has higher content of panaxydol. Especially, panaxydol was not detected in the callus induced from cell line 10301 which cultured on the medium containing CPA only, however, it was detected on the same callus cultured on mixed medium containing CAP 2 mg/L and BA 0.05 mg/L. SH medium was better than MS medium for ginseng callus growth and biosynthesis of polyacetylene, and also found that it was not effected by NAA and sucrose concentration in the culture medium.

• Korean Journal of Plant Tissue Culture
• /
• v.27 no.2
• /
• pp.125-131
• /
• 2000

Protoplasts of Arabidopsis thaliana were easily isolated from the shoot-forming (SF) suspension-cultured cell clusters with 4 hours-shaking condition (40 rpm) on CPD enzyme solution containing 1% cellulase R-10, 0.25% pectolyase Y-23 and 0.5% driselase. Protoplasts were cultured on liquid KAO medium supplemented with 1 mg/L 2,4-D, 0.5 mg/L kinetin, 200 mg/L spermidine and 68 g/L glucose. Also, protoplasts were cultured on 0.2 $\mu$M membrane filter placed onto CP solid medium containing the suspension cells as feeder cells in the dark at $25^{\circ}C$ for 4 weeks. Protoplast-derived-SF calli were cultured on MS medium containing 0.05 mg/L IAA, 7 mg/L 2 ip and 30 g/L sucrose under the continuous illumination for four weeks. The frequency of shoot formation was about 60%. The regenerants were transferred into potting soil to grow mature plants. The regenerants formed the silques with seeds after 8 weeks of cultures.

• Journal of Plant Biotechnology
• /
• v.29 no.4
• /
• pp.241-246
• /
• 2002

Somatic embryos or adventitious buds were formed from the segments of zygotic embryo of Lycium chinense Mill. on Murashige and Skoog (MS) medium supplemented with auxins (2,4-D, NAA, IAA) and / or cytokinins (zeatin, kinetin, BAP). Embryogenic callus formed on MS medium containing 0.5 mg/L 2,4-D and then differentiated into somatic embryos without transfer to hormone free medium. On the other hand, adventitious buds were formed on medium with 0.01 mg/L 2,4-D and 0.5 mg/L zeatin. Among various parts of zygotic embryos, the morphogenic potential was higher in the cotyledonary region, and the most organogenic potential was found in cotyledon followed by radicle, hypocotyl, and whole embryo. Histologically, bipolar structure of the heart-shaped embryos were confirmed and in adventitious buds only shoot apical meristems were found to exist.

• Korean Journal of Plant Tissue Culture
• /
• v.26 no.3
• /
• pp.149-156
• /
• 1999

In order to investigate the effect of low temperature pretreatment on pollen dimorphism and embryo formation in anther culture of Platycodon grandiflorum, the anthers with microspore at the uninucleate stage were cultured on Murashige and Skoog medium supplemented with 0.5mg/L NAA and 1.0 mg/L BA. The low temperature pretreatment have clear effect on the frequencies of S pollen grains, symmetrical binucleate microspores (B type of S pollen), multinucleate and multicelled pollen grains. Especially, after low temperature pretreatment at 8$^{\circ}C$ for 5 days increased the frequency of S pollen grain (20.6%) in vivo. In addition, the highest frequency of callus induction (54.9%) and embryo formation (9.9%) were obtained from the anther pretreatment at 8$^{\circ}C$ or 5 days. Three distinct pathways could be recognized in the androgenesis, one involving mainly the vegetative cell, the second starting with the vegetative and the generative cell, respectively, and the third accompaning with two equal vegetative type cells in the pollen grains.

• Journal of Plant Biotechnology
• /
• v.31 no.2
• /
• pp.121-126
• /
• 2004

Bleeding heart (Dicentra spectabilis L. Lemaire) is one of the most valuable wild flower in Korea. This work was conducted for the mass production of somatic embryos through suspension culture and more effective plant regeneration system in Dicentra spectabilis. High-frequency embryogenic callus proliferation was achieved in SH liquid medium supplemented with 1 mg/L 2,4-D. Half-strength SH medium was suitable concentration for somatic embryo induction and germination. About 5,000 embryos were produced per 250$m\ell$ flask after 4 weeks of culture. Germination rate of somatic embryos was decreased when GA$_3$ was added in medium. The plantlets showed a 58％ survival rate when transferred to pots after 1 month of culture. The results indicate that micropropagation procedure via somatic embryogenesis can be applied for an efficient mass propagation of Dicentra spectabilis.

• Journal of Plant Biotechnology
• /
• v.31 no.2
• /
• pp.175-178
• /
• 2004

Transgenic tobacco (Nicotiana tabacum L. cv Bright Yellow-2) cell lines expressing a human histone H1.5 (referred to as hH1.5), which suppress collagen-induced rheumatoid arthritis, were developed under the oxidative stress-inducible peroxidase (SWPA2) promoter. Tobacco BY-2 cells were transformed by Agrobacterium-mediated method. The kanamycin-resistant calli were selected on the modified MS medium containing 150mg/L kanamycin and 300mg/L claforan. Transgenic cell lines were confirmed by PCR and northern blot analysis. Recombinant hH1.5 (rhH1.5) protein (42 kDa) was also detected by Western blot analysis, showing a different molecular weight of human hH1.5 (32 kDa). These results suggested that a hH1.5 gene was properly introduced in tobacco cultured cells under the control of SWPA2 promoter. The further characterization of rhH1.5 protein remains to be studied.

• Korean Journal of Plant Tissue Culture
• /
• v.25 no.5
• /
• pp.329-333
• /
• 1998

$\beta$-Glucuronidase (GUS) gene of Escherichia coli was introduced into sweet potato (Ipomoea batatas (L.) Lam.) cells by particle bombardment and expressed in the regenerated plants. Microprojectiles coated with DNA of a binary vector pBI121 carrying CaMV35S promoter-GUS gene fusion and a neomycin phosphotransferase gene as selection marker were bombarded on embryogenic calli which originated from shoot apical meristem-derived callus and transferred to Murashige and Skoog (MS) medium supplemented with 1 mg/L 2,4-dichlorophenoxyacetic acid and 100 mg/L kanamycin. Bombarded calli were subcultured at 4 week intervals for six months. Kanamycin-resistant calli transferred to MS medium supplemented with 0.03 mg/L 2iP, 0.03 mg/L ABA, and 50 mg/L kanamycin gave rise to somatic embryos. Upon transfer to MS basal medium without kanamycin, they developed into plantlets. PCR and northern analyses of six regenerants transplanted to potting soil confirmed that the GUS gene was inserted into the genome of the six regenerated plants. A histochemical assay revealed that the GUS gene was preferentially expressed in the vascular bundle and the epidermal layer of leaf, petiole, and tuberous root.

• Journal of Animal Environmental Science
• /
• v.19 no.1
• /
• pp.55-62
• /
• 2013

Teff grass is a warm season C4 annual grass that is used for dry hay, silage and haylage. We have developed a high-frequency plant regeneration system for teff grass via callus culture using mature seeds. It was revealed that mature seeds cultured on MS medium supplemented with 2 mg/l 2,4-D, 0.5 g/L proline, 0.5 g/L casamino acid and 3 g/L Gelrite under light condition produced the highest percentage of callus formation (91.9%). Addition of cytokinins (BA) at 0.0~0.5 mg/L to media containing 2 mg/l 2,4-D enhanced callus growth. The most suitable medium for plant regeneration from dehydrated calli was MS agar medium supplemented with 0.1 mg/l NAA, 1 mg/l BA, 0.5 g/L proline, 0.5 g/L casamino acid 3 g/L Gelrite which induced the highest percentage of calli forming shoots (47.0%). The shoots were rooted at the highest rate (100%) when transferred onto 1/2 MS medium and acclimated in greenhouse conditions.