• Journal of Plant Biotechnology
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• v.36 no.2
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• pp.170-173
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• 2009

Leaf and petiole explants of Pulsatilla koreana NAKAI were cultured on MS medium supplemented with various concentrations of zeatin, kinetin or BAP combined with 0.05 mg/L IAA. After 6 weeks of culture, effects of cytokinin on adventitious shoot formation from explants were investigated. The highest frequency of shoot formation was obtained when petiole explants were cultured on medium with 0.5 mg/L zeatin and 0.05 mg/L IAA. Regenerated shoot were transferred on to root induction medium. The best root formation was observed at 1/2 MS medium with 1.5 mg/L NAA. Rooted plantlets were transplanted to a mixture of perlit and soil (1:3), where they were successfully acclimatized.

• Journal of Plant Biotechnology
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• v.4 no.1
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• pp.33-37
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• 2002

Micropropagation and adventitious root production via the culture of Polygonatum odoratum were performed. Stem segments of seedlings of Polygonatum odoratum were the most efficient explants for adventitious shoot formation compared to leaf and root segments. Exogenous cytokinin treatment was required for adventitious shoot formation. Among the cytokinin (BA, Kinetin and Zeatin) tested, BA was most effective for shoot formation from stem segments. Auxin (NAA or IBA) in combination with cytokinin significantly enhanced adventitious shoot formation. Twenty five percent of explants produced adventitious shoots on medium with 2.0 mg/L BAP alone, while 83% of explants produced adventitious shoots on medium with the combination of 2.0 mg/L BAP and 0.1 mg/L IBA. Rooting of adventitious shoots was achieved after transferring to 112 MS medium supplemented with 0.1 mg/L IBA and 0.5 mg/L zeatin. When stem segments were cultured on MS medium with various kinds of auxin (IBA, NAA and 2,4-D), adventitious roots were formed from callus. frequency of adventitious root formation was highest in 2,4-D than NAA and IBA. When roots were in clusters together with parental stem segments, growth of roots actively occurred in hormone-free MS liquid medium. The above results represent that possible application for the mass production of roots and plantlets through in vitro culture system of Polygonatum odoratum.

• Korean Journal of Plant Tissue Culture
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• v.24 no.3
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• pp.125-128
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• 1997

The most effective cytokinin source for adventitious shoot regeneration of in vitro grown leaves from 'Gala' apple was BA with the concentration of 4.0 mg/L, while auxin source was IAA, IBA and NAA with the concentration of 0.1 mg/L, respectively. As the result of combinational treatment of BA and NAA, 6.0 or 8.0 mg/L BA with 0.5 mg/L NAA was effective for adventitious shoot regeneration from leaf tissues of 'Gala', 0.1 mg/L NAA + 8.0 mg/L BA and 1.0mg/L NAA + 8.0 mg/L BA for internode, and 0.1 mg/L NAA + 4.0 mg/L BA for petiole.

• Molecules and Cells
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• v.44 no.10
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• pp.746-757
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• 2021

Plant somatic cells can be reprogrammed into a pluripotent cell mass, called callus, which can be subsequently used for de novo shoot regeneration through a two-step in vitro tissue culture method. MET1-dependent CG methylation has been implicated in plant regeneration in Arabidopsis, because the met1-3 mutant exhibits increased shoot regeneration compared with the wild-type. To understand the role of MET1 in de novo shoot regeneration, we compared the genome-wide DNA methylomes and transcriptomes of wildtype and met1-3 callus and leaf. The CG methylation patterns were largely unchanged during leaf-to-callus transition, suggesting that the altered regeneration phenotype of met1-3 was caused by the constitutively hypomethylated genes, independent of the tissue type. In particular, MET1-dependent CG methylation was observed at the blue light receptor genes, CRYPTOCHROME 1 (CRY1) and CRY2, which reduced their expression. Coexpression network analysis revealed that the CRY1 gene was closely linked to cytokinin signaling genes. Consistently, functional enrichment analysis of differentially expressed genes in met1-3 showed that gene ontology terms related to light and hormone signaling were overrepresented. Overall, our findings indicate that MET1-dependent repression of light and cytokinin signaling influences plant regeneration capacity and shoot identity establishment.

• Journal of Plant Biotechnology
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• v.29 no.2
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• pp.123-127
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• 2002

Effect of cytokinins (BA, TDZ, zeatin, 2iP, and kinetin) applied either singly or in combination on in vitro growth of two grape cultivars ('Cabernet Sauvignon' and 'Campbell Early') was investigated as a serial work for mass production of grapevine nursery stocks. In single treatment, shoot growth of two cultivars was most favorable in control. Shoot proliferation was satisfactory with 10 $\mu$M BA regardless of cultivars and cytokinin combinations, followed by TDZ. Other treatments resulted in very poor or no branching. Total explants ready for subculture produced by 10 $\mu$M BA outnumbered those by other treatments. TDZ was also effective. TDZ significantly increased the fresh weight and callus formation while shoot growth was unsatisfactory. Shoot growth response of two cultivars in combined treatments was also most favorable in control as was in single treatments. When TDZ was combined with zeatin, 2iP, and kinetin which failed to induce branching, proliferous branching was induced though the shoot number was behind that of single treatments of BA and TDZ. TDZ was very effective for total number of explants and fresh weight, showing 10-fold increase.

• Korean Journal of Agricultural Science
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• v.13 no.2
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• pp.168-175
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• 1986

Leaf segments of tomato (Lycopersicum escullentum Mill) were cultured on the MS medium supplemented with the concentration of 0, 0.2, 0.5, 2.0 or $5.0mg/{\ell}$ NAA, 2,4-D and/or BA. The treatments were able to induced callus, however the best combinations for the induction of callus were $2.0mg/{\ell}$ BA and 2.0 or $0.5mg/{\ell}$ NAA. Shoot formation was stimulated at the treatment of 2.0 or $5.0mg/{\ell}$ BA, and root formation was stimulated on the medium of 0.2, 0.5, 2.0 or $5.0mg/{\ell}$ NAA plus 0, 0.2 or $0.5mg/{\ell}$ BA.

• Proceedings of the Zoological Society Korea Conference
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• 1997.10b
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• pp.199.2-199
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• 1997

• Journal of Plant Biology
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• v.31 no.2
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• pp.121-130
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• 1988

In order to clarify effects of phytohormones on the viability and the cell wall regeneration of protoplasts isolated from Nicotiana tobacum L. var. BY4, protoplasts isolated from mesophyll tissue were cultured on the Murashige-Skoog liquid media supplemented with auxin(2, 4-D, NAA, IAA) and/or cytokinin (kinetin, BAP, 2ip). Viability of protopplasts was higher in the culture medium containing auxin and cytokinin, especially in the combination of 2, 4-D and BAP. The effectual cell wall regeneration of protolasts was observed when theprotoplasts were cultrued on the medium supplemented with auxin alone, especially with IAA. Cell wall regernation started from 2-3 days after culture and was not detected at budding regions. When the protoplasts were cultured on the phytohormone-free medium, the viability of protoplasts dramatically decreased 4 days after culture.

• Plant Resources
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• v.8 no.3
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• pp.286-292
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• 2005

Shoot induction system was developed in the recalcitrant plant species, Brassica rapa ssp. rapifera by using optimum selection of profit organ, phytohormone combination, seedling age and kind of culture container. Out of in vitro cultured leaf segment, petiole, hypocotyl, and cotyledon with petiole, only cotyledon with petiole derived from 4 day-old seedlings induced multiple shoot. The optimum combination of auxin and cytokinin for the multiple shoot induction was MS medium containing 5mg/L BA and 0.5mg/L NAA. The major factors for multiple shoot propagation were part of plant organ, age of seedling, and ratio of auxin and cytokinin. In addition, shoot regeneration was promoted in the 100ml Erlenmeyer flask compared with the $90mm{\times}20mm$ Petri-dish. The induced shoots formed roots easy on MS medium containing 0.1mg/L IBA and the whole plants were successfully cultivated in soil.

• Plant Resources
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• v.7 no.1
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• pp.1-6
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• 2004

In vitro proliferation system was achieved by using nodal segment excised from greenhouse grown juvenile stock plants of Alnus japonica. Stem explants were cultured on MS medium supplemented with different plant growth regulators of cytokinin and/or their combinations. The most effective cytokinin source was the combination of zeatin 2.0 mg/L and TDZ 0.05 mg/L producing the average number of shoots (16.8 $\pm$ 3.6). In addition, healthy roots were formed after small clumps of shoots were transferred to half strength of MS medium containing IBA 0.02 mg/L with optimal rooting capacity. Soil acclimatization was successfully conducted in cell tray containing artificially mixed soil with 92 % survival rate.