• KOREAN JOURNAL OF CROP SCIENCE
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• v.49 no.1
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• pp.52-60
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• 2004

The optimized in vitro culture system was investigated for improvement of regeneration efficiencies by observing the responses of scutella-derived callus of Korean rice (Oryza sativa L.). Large variations of callus induction (43.9-93.9%) and shoot regeneration (0-88.7%) were observed among the rice cultivars depending on medium. However, shoot regeneration was significantly improved by selected utilization of basal medium, growth regulators, and carbon sources. N6 basal medium was more efficient for embryogenic callus induction than MS or LS basal medium, while MS was superior to N6 for shoot regeneration. The calli of highly regenerative cultivars grew faster and showed higher rates of green tissue formation (GT) and shoot regeneration (SR) and lower rate of callus browning (CB) than those of recalcitrant cultivars. Although a higher level of kinetin stimulated the GT and SR in highly regenerative cultivars, $10\textrm{mgL}^{-1}$ kinetin generally suppressed the GT and SR, while CB was accelerated compared to $2\textrm{mgL}^{-1}$ kinetin. Additional benefits of sorbitol combined with maltose (or sucrose) under $5\textrm{mgL}^{-1}$ kinetin were certainly confirmed on regeneration efficiencies compared to sucrose alone as carbon source and osmotic regulator. This combination showed high rate of GT and SR with multiple shoots while low rate of CB. With MSRK5SM-Pr medium ($5\textrm{mgL}^{-1}$ kinetin, 3% sorbitol, 2% maltose, $500\textrm{mgL}^{-1}$ proline), the regeneration efficiencies of total 17 out of 24 cultivars were practically improved 160% on average compared to MSRK2S ($2\textrm{mgL}^{-1}$ kinetin, 3% sucrose) control medium. Especially, the medium was most effective to the cultivars showing a medium level of regenerability such as Daesanbyeo and Dongjinbyeo and Suwon477, enhancing efficiencies more than 300-600% compared to MSRK2S medium.

• Journal of Plant Biotechnology
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• v.30 no.4
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• pp.341-346
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• 2003

In an effort to optimize tissue culture conditions for genetic transformation of orchardgrass (Dactylis glomerata L.), an efficient and high-frequency plant regeneration system from seed-derived calli was established. Embryogenic calli induced on MS medium containing 3mg/L 2,4-D and 0.1mg/L BA had significantly improved regeneration ability. Plant regeneration rate was 92％ when embryogenic calli were cultured on N6 medium supplemented with 1mg/L 2,4-D and 3mg/L BA. Among three kinds of medium, MS and N6 medium were optimal for embryogenic callus induction and plant regeneration, respectively. Ho difference in callus induction frequency was observed among four cultivars of orchardgrass, however, "Roughrider" cultivar showed higher regenerability with the frequency of 61％. Addition of maltose to the regeneration medium as a carbon source dramatically increased regeneration frequency up to 69％. A short tissue culture period and high-frequency regeneration system would be beneficial for molecular breeding of orchardgrass through genetic transformation.

• Korean Journal of Medicinal Crop Science
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• v.14 no.5
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• pp.293-298
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• 2006

Optimum culture conditions for high frequency plant regeneration from leaf explants of Kalanchoe daigremontiana Hamet &Perrier were established. Shoot regeneration was achieved from leaf explant cultures using MS medium supplemented with indole-3-acetic acid (IAA) and thidiazuron (TDZ) or benzyladenine (BA). Percent regeneration was influenced by plant growth regulators and source of explants. MS medium supplemented with TDZ (1.0 mg/l) and IAA (0.4 mg/l) was the most effective, providing shoot regeneration for 76.7 % of ex vitro leaf explants associated with a high number of shoots per explant (9.5 mean shoots per explant), whereas 100% shoot regeneration associated with 12.4 shoots per explant occurred from in vitro leaf explants on the same medium. Clusters of shoots were multiplied and elongated on MS medium containing several concentrations of BA. MS medium supplemented with 0.25 mg/l BA was proved as the most effective shoot elongation medium. Elongated shoots (2-3 cm) were rooted at 100% on half-strength MS medium. Rooted plantlets were then transferred to potting soil. Regenerated plants were established in the soil with 90% success.

• Asian Journal of Turfgrass Science
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• v.12 no.4
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• pp.195-202
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• 1998

The development of a protocol for high efficiency of embryogenic callus separation, maintenance and plant regeneration from the seeds of zoysiagrass cv. Zenith was studied. Embryogenic callus ratio is absolutely determined by genotype, but by adding high concentration of copper into medium, changing light condition and maintaining callus on initial induction medium for 8∼10 weeks, embryogenic callus can be easily distinguished and its growth can be promoted. There were significant differences among selected callus lines (each from one seed) according to their growth rates and regeneration percentages. Callus pre-treatment with activated charcoal inhibited callus growth, increased the level of precocious germination during culture and promoted shoot cluster formation after transfer to regeneration medium. For long-term callus maintenance, N6AA medium was better than MS medium, because the former inhibited non-embryogenic callus formation and kept vigor of embryogenic callus. The best callus lines Z-(5) has been successfully used for transformation and somaclonal variation selection in our laboratory.

• Journal of The Korean Society of Grassland and Forage Science
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• v.21 no.2
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• pp.45-48
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• 2001

In an effort to optimize tissue culture responses of tall fescue, the effects of basic medium and carbon sources on seed culturability and genotypic difference of plant regenerability were investigated. The MS basal medium was superior to $N_{5}$ 6/ and $B_{medium}$ in enhancing callus growth and plant regeneration. To determine the effect of carbon sources on plant regeneration, the seeds were cultured on medium with 30 g/L sucrose and maltose, respectively. Medium supplemented with 30 g/L sucrose resulted in regeneration of shoots from 50% of the calli. The genotypic difference in plant regenerability was obvious among five cultivars of tall fescue tested. \\`KY31\\` and \\`Hokuryo\\` showed to have higher regenerability with the frequency of 33% and 51%, respectively.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.47 no.5
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• pp.352-355
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• 2002

Mature embryos of five oat genotypes were cultured to develop an efficient method of callus induction and plant regeneration. Murashige and Skoog(MS) and N6 media supplemented with 2,4-dichlorophenoxyacetic acid (2,4-D) and kinetin were used for callus induction. Percentage of callus induction showed significant among the combinations of plant growth regulators. Callus induction showed high efficiency in medium containing 3 mg/$\ell$ of 2,4-D. The high frequency of callus induction was obtained in Gwiri37. For plant regeneration, calli induced from mature embryos were transferred onto MS and N6 media supplemented with combinations of 6-benzyladenine (BA) and naphthaleneacetic acid (NAA) for 5 weeks. Percentage of plant regeneration showed high in MS medium containing 0.2 mg/$\ell$ of NAA and 1 mg/$\ell$ of BA. The callus initiation medium affected the subsequent plant regeneration. Treatment with 3 mg/$\ell$ of 2,4-D, and 3 mg/$\ell$ of 2,4-D and 3 mg/$\ell$ of kinetin in callus induction media showed high frequency for plant regeneration. Plant regeneration frequency among the genotypes showed significant. Especially, Gwiri37 showed high regeneration frequency. Regenerated shoots were treated with 200, 350 and 500 mg/$\ell$ of indole-3-butyric acid (IBA) transferred onto half-strength MS medium without plant growth regulators. Treatment of shoots with IBA induced root formation rapidly.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.49 no.4
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• pp.349-353
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• 2004

Mature embryo and leaf base segment of Korean oat were used as materials in an experiment to check plant regeneration efficiency. MS media supplemented with 2,4-dichlorophenoxyacetic acid (2,4-D), kinetin, and picloram were used for callus induction from mature embryos and leaf base segments. Three mg/l of 2,4­D and 3 mg/l of picloram in callus induction medium showed high frequency for plant regeneration from mature embryos. Leaf base segments were transferred to callus induction medium and incubated at $25^{\circ}C$ in 16/8 hr light/dark cycle for 3 weeks. Callus induction from leaf base segments of Malgwiri showed high efficiency in medium containing 3 mg/l of 2,4-D and 1 mg/l of kinetin $(91.8\%)$. In case of Samhangwiri, the combinations of phytohormones did not show significant difference. Regeneration from leaf base segments showed high frequency in shoot medium containing 1 mg/l of antiauxin, tri-iodobenzoic acid (TIBA) and 1 mg/l of 6-benzyladenine (BA). Calli induced from leaf base segments of Samhangwiri and Malgwiri in media containing 3 mg/l of 2,4-D and 3 mg/l of picloram showed high regeneration frequency. It appears that the callus initiation medium may be an important factor for subsequent plant regeneration.

• Korean Journal of Plant Tissue Culture
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• v.28 no.4
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• pp.205-208
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• 2001

This study was conducted to improve the regeneration efficiency from seed-derived calli of rice by optimizing the copper concentrations in the media. Mature seeds were cultured on MS medium supplemented with copper sulphate (0 to 5.0 mg/L) and 2 mg/L 2,4-D. Callus growth was influenced by the levels of copper sulphate containing with medium, The addition of copper sulphate (2.5 mg/L) in regeneration medium enhanced dramatically the ability of plant regeneration from seed-derived calli. The mean frequency of plant regeneration of 6 indica rices was 27.4% on medium containing copper sulphate, whereas that of the cultivars on copper-free medium was 2.4%. These results suggest that copper sulphate may have an important role in improving regeneration ability of indica rices.

• Korean Journal of Plant Resources
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• v.10 no.1
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• pp.94-99
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• 1997

When the leaf and stem tissues of Rehmannia glutinosa were cultured on MS medium with plant growth regulators, shoots were regenerated on MS medium with TDZ(0.01 to $2.0{\mu}M$), and root initiation was better on MS medium treated with NAA(0.01 to 2.0mg/$\iota$). On $B_5$ medium, shoot regeneration was better on medium with TDZ than those with Quincrac, NAA, and 2.4-D. The addition of Quincrac, NAA, and 2.4-D inhibited shoot regeneration on MS medium, but promoted shoot regeneration on $B_5$ medium. Shoot regeneration and growth was better on MS medium with the combination treatments of 2.4-D 0.01mg/$\iota$ and TDZ 0.01, 0.1 and $2{\mu}M$ compared with other treatments. Also shoot regeneration and growth on B_5 medium showed the similar results to that on MS medium.

• Journal of Life Science
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• v.11 no.4
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• pp.311-315
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• 2001

To identify the effects embryo developmental stage and gelrite concentration on plant regeneration in seed culture of rice, mature and immature seeds of rice were cultured on the $N_{6}$ medium supplemented with2 mg/$\ell$ 2.4-D and different levels of gelrite(0.2~1.0%). The calli formed immature embryos were produced more plants than those from mature embryos. The maximum frequency of plant regeneration was achieved in the culture of the calli of immature embryos which was harvested at the 21$^{th}$ day after pollination. The plant regeneration on the medium with gelrite was more accelerate than that on the medium with agar. The highest frequency(55%) of plant regeneration was obtained from the calli transferred to the medium with 6g/$\ell$ gelrite.