• Korean Journal of Medicinal Crop Science
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• v.13 no.4
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• pp.133-137
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• 2005

Experiments were conducted to find the optimal acclimatization conditions for Eleutherococcus senticosus plantlets regenerated from bioreactor cultured somatic embryos, various acclimatizing conditions were compared regarding both survival rate and growth of the plantlets. Among the various temperature and artificial soil tested, the highest survival rate (88%) was observed when plantlets were acclimatized in Klasmann bed soil at $10^{\circ}C$ When in vitro plantlets directly transplanted to field environment, shading treatment was necessary and 50% shading was more effective than 30% shading. Transplanting season were also important for successful acclimatization of in vitro cultured plantlets, transplanted on March 20 with 50% shading exhibited the best survival rate and further growth.

• Plant Biotechnology Reports
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• v.2 no.3
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• pp.207-212
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• 2008

Plantlets of Alocasia amazonica regenerated under a photon flux density (PFD) of 15 or $30{\mu}mol\;m^{-2}s^{-1}$ showed better growth and development than those grown under higher PFDs. While chlorophyll a and chlorophyll b decreased, the number of stomata increased with increasing PFD. Photoperiods also affected plantlet growth and stomatal development. Highest growth was observed for the short photoperiod (8/16 h) and for equinoctial (12/12 h) light and dark periods. Very few stomata developed in the leaves of plantlets grown under a short photoperiod (8/16 h) and the number of stomata increased with increasing light period. In conclusion, both light intensity and photoperiod independently affect growth of A. amazonica and development of stomata, depending on the intensity and duration of light treatment.

• Journal of Plant Biotechnology
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• v.6 no.2
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• pp.87-90
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• 2004

An efficient plant regeneration system in alfalfa (Medicago sativa L.) through somatic embryogenesis was established. Embryogenic callus was obtained by culture of hypocotyl segments on MS medium with 0.02mg $L^{-1}$ IAA and 1.0mg $L^{-1}$ zeatin after 45 days of culture. Embryogenic calli were converted to the somatic embryos when transferred to either MS medium without plant growth regulators (PGRs) or MS medium containing various cytokinin (BA, kinetin and zeatin). Most of the somatic embryos were developed into plantlets on MS medium supplemented with 0.1 mg $L^{-1}$ kinetin. Also, secondary embryos appeared on the surface of primary embryo but they showed abnormal growth. Regenerated plantlets were transplanted to pots containing vermiculite and perlite for further analysis.

• Plant Biotechnology Reports
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• v.3 no.3
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• pp.199-203
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• 2009

Rugosa rose (Rosa rugosa) is cultivated as a garden flower and an important genetic resource for the breeding of roses (R. hybrida). This study describes culture conditions for high frequency plant regeneration from zygotic embryo explants via somatic embryogenesis in rugosa rose. Mature zygotic embryo, cotyledon, and radicle explants formed embryogenic calluses at frequencies of 38, 6.7, and 8.8% when cultured on half-strength Murashige and Skoog medium (${\frac{1}{2}}MS$) supplemented with 2.26, 9.05, and $9.05{\mu}M$ 2,4-dichlorophenoxyacetic acid, respectively. Embryogenic calluses produced numerous somatic embryos, which then developed into plantlets on ${\frac{1}{2}}MS$ without growth regulators. Regenerated plantlets were grown to whole plants in a growth chamber.

• Korean Journal of Plant Resources
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• v.16 no.1
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• pp.49-54
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• 2003

Effects of cutting time and scions section on shooting and plantlets growth characteristics were investigated to increase plantlets products by root cuttings in lacquer tree. Shoot induction from scion section was developed lately as it planted in earlier season. However, shooting rates were over 84% or more in cut planting on 15, 25 March and 5 April than sinee 15 April. Shoots were developed evenly as late cut planting. Generally, plant height, branch number, leaf number, stem diameter, and leaf area per plantlets was excellent in cut planting on 25 March and 5 April. Shooting rate from the root scion varied greatly by root sectionings. The rate of the 10 cm-long-scion was reached 84％, whereas only 54％ in no trimmed root scion after 10 weeks of cutting. Regenerated plantlets from root scion without cut were slightly good in shape, but their height, number of branch per plantlets, and stem diameter were not significant.

• Journal of Plant Biotechnology
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• v.2 no.3
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• pp.151-155
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• 2000

Shoot proliferation was obtained from shoot tips and nodal explants of Vitex negundo L. on MS medium supplemented with either BAP or KIN (0.1-2.0 mg/L) alone or in combination with NAA (0.1 mg/L). The concentrations of cytokinins combined with NAA produced multiple shoots from shoot tips and nodal explants. The highest mean percentage (84.3$\pm$8.0) of shoot multiplication's were observed on nodal explants in the presence of BAP (1.5 mg/L) and NAA (0.1 mg/L) followed by shoot tips (65.0$\pm$5.0). The regenerated shootlets were rooted on MS basal medium IAA, IBA, NAA (0.1-1.5 mg/L). The maximum number of roots (51.0$\pm$2.6) was achieved on the medium containing IBA (1.0 mg/L) followed by other auxins (NAA, IAA). The regenerated plants were successfully transferred to a mixture of vermiculate and soil. About 95% of the plantlets survived when transferred to the field.

• Journal of Plant Biotechnology
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• v.3 no.1
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• pp.13-17
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• 2001

A Chromium (VI)[Cr(VI)] reductase gene from heavy metal reducing bacteria Pseudomonas aeruginosa HP014 was used to transform tobacco plant cells. A chimeric construct containing the Cr(VI) reductase gene was transfered to tobacco leaf disks using an Agrobacteriun tumefaciens binary vector system. From the leaf disks, transformed plantlets were regenerated. Hybridization experiments demonstrated that the Cr(VI) reductase gene was inserted into and expressed in the regenerated plants. The Cr(VI) reduction activity showed that the transgenic plants may be a another possible tool to reduce the pollution of the toxic Cr(VI) in soil.

• Korean Journal of Plant Resources
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• v.7 no.1
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• pp.17-22
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• 1994

This study was carried out to investigate the optimum medium and concentrations of growth regulators for induction of multiple shoot by meristem culture of floe otorefcenf Mill. MS medium supple-mented with 3${\mu}{\textrm}{m}$ TDZ was effective for induction of multiple shoot. Shoot multiplication was more ef-fective when 2mg/1 BA combined with 0.Img/1 IAA than when only BA were treated on medium. Halfstrength of MS medium supplemented with 2mg/L IAA was effective for rooting of shoots regenerated.When plantlets regenerated from meristem culture were transferred to pot, survival rate of plantletswas 80% on perlite and was 95% on vermiculite, respectively.

• Plant Biotechnology Reports
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• v.4 no.4
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• pp.303-309
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• 2010

Endoreduplication is a developmental process that is unique to plants and occurs in all plants. The present study aimed to assess endoreduplication in various explant tissues and regenerated somatic embryos of Doritaenopsis. We further investigated the effects of light quality on endoreduplication and somatic embryo proliferation. To this end, we studied endoreduplication in leaves and root tips from regenerated plantlets and somatic embryos and in developing somatic embryos under 4 types of lighting conditions: red light, red + far-red light, red + blue light, and white light. We found that the degree of endoreduplication varied in different explants, and that the choice of explants used also influenced the ploidy levels of the newly regenerated somatic embryos. The DNA content of the leaf (2C-8C) was less than that of the root tip (2C-16C) and somatic embryo (2C-64C). In terms of light quality, the combination of red and far-red light produced the highest number of somatic embryos, while maintaining a low degree of endoreduplication. The data obtained indicate that this light combination stimulates somatic embryogenesis in Doritaenopsis and may exert some control on endoreduplication during cell division. These findings can be applied to achieve a reduction in somaclonal variations for the purpose of mass proliferation and genetic improvement.

• Korean Journal of Plant Resources
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• v.16 no.2
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• pp.160-167
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• 2003

In order to investigate the effects of developmental stage of embryos and plant growth regulators on mass production of Zantedeschia spp. Southern Light, immature zygotic embryos of Zantedeschia spp. Southern Light were cultured on Murashige and Skoog(1962) basal media or containing 2,4-D, NAA and BA. Globular embryos did not grow on any of the 2,4-D, NAA and BA combinations. The most suitable stage of immature zygotic embryo culture on the induction callus and multiple shoot was at early cotyledonary embryo stage, and at this stage of embryos were germinated up to 87.5%. The whitish watery callus and yellowish compact nodular callus produced on all 2,4-D, NAA and BA media. The best combination for inducing embryogenic callus was 0.5 mgL NAA and 1.0 mg/L BA. Whitish watery calli have been subcultured for more than 8 months and have retained their producing ability, Plant regeneration was only obtained by direct shoot development and yellowish compact nodular calli. Abundant plantlets were regenerated from cotyledonary stage of embryo culture on MS medium supplemented with 0.5 mg/L NAA and 1.0 mg/L BA. Supplementation of the media with 10％ coconut water showed as the best concentration for plant differentiation from direct developed of shoots. The number of regenerated plants from one embryo could be seperated 25-35s plantlets. All yellowish compact callus-derived plantlets were transferred to pots containing a mixture of vermiculite, perlite and sand(1:1;1 v/v) and 100% of divided plantlets were phenotypically normal.