• Journal of Plant Biotechnology
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• v.6 no.2
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• pp.77-85
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• 2004

Development of efficient plant regeneration and genetic transformation protocols (using the Particle Inflow micro-projectile Gun and the shoot-tips as target tissue) of Sorghum bicolor (L.) Moench in terms of expression of the reporter gene, $\beta$-glucuronidase(uidA) is reported here. Two Indian cultivars of sorghum were used in the study, viz. M-35-1 and CSV-15. Plant regeneration was achieved from one-week-old seedling shoot-tip explants via multiple-shoot-clumps and also somatic embryos. The multiple-shoot-clumps were produced on MS medium containing BA (0.5, 1.0 or 2.0 mg/$L^{-1}$), with biweekly subculture. Somatic embryos were directly produced on the enlarged dome shaped expansive structures that developed from shoot-tip explants (without any callus formation) when cultured on MS medium supplemented both with BA (0.5, 1.0 or 2.0 mg/$L^{-1}$) and 2,4-D (0.5 mg/$L^{-1}$). Whereas each multiple-shoot-clump was capable of regenerating more than 80 shoots via an intensive differentiation of both axillary and adventitious shoot buds, the somatic embryos were capable of 90% germination, plant conversion and regeneration. The regenerated shoots could be efficiently rooted on MS medium containing 1.0mg/$L^{-1}$ IBA and successfully transplanted to the glasshouse and grown to maturity with a survival rate of 92%. The plant regeneration efficiency of both the genotypes were similar. After the micro-projectile bombardment, expression of uidA gene was determined by scoring blue transformed cell sectors in the bombarded tissue by an in situ enzyme assay. The optimal conditions comprising a helium pressure of 2200 K Pa, the target distance of 11 cm with helium inlet fully opened and the use of osmoticum have been defined to aid our future strategies of genetic engineering in sorghum with genes for tolerance to biotic and abiotic stresses.

• Journal of Plant Biotechnology
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• v.34 no.4
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• pp.293-298
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• 2007

Robinia pseudoacacia var. umbraculifera, commonly called umbrella black locust were regenerated after co-cultivation of internode segments with Agrobacterium tumefaciens which included yeast cadmium factor 1 (YCF 1) gene. The tolerance to cadmium and lead for plants can be increased by the YCF1 gene expression. Moreover, the recent studies have shown that YCF1 gene transgenic plants increase the accumulation of cadmium and lead into plant vacuoles. The effect of plant growth regulator such as 2,4-dichlorophenoxyacetic acid (2,4-D), ${\alpha}$-naphthaleneacetic acid (NAA), 6-benzyladenine (BA), and thidiazuron (TDZ) were studied to evaluate the propagation of plants through internode explants. The efficient induction of multiple adventitious shoots and callus were observed on a medium supplemented with 0.1 mg/L TDZ + 0.2 mg/L BA. To induce shoot elongation and rooting, regenerated shoots were transferred into basal MS medium without any plant growth regulator. Successful Agrobacterium tumefaciens mediated transformation was obtained by 20 min vacuum-infiltration with $50{\mu}M$ acetosyringone on the optimal multiple shoot induction medium with 30 mg/L hygromycin and 300 mg/L cefotaxime. To confirm the integration and expression of transgene, Polymerase Chain Reaction (PCR) and Reverse Transcriptase PCR (RT-PCR) were performed with specific primers. The frequency of transformation was approximately 18.94%. This study can be used to genetic engineering of phytoremediator.

• Proceedings of the Korean Society of Plant Biotechnology Conference
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• 2002.04b
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• pp.181-181
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• 2002

• Journal of Applied Biological Chemistry
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• v.42 no.3
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• pp.113-118
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• 1999

The transgenic plant of Citrus species (Citrus aurantium L.) was constructed with a fatty acid desaturase gene using microprojectile bombardment transformation system. The DNA of a fatty acid desaturase gene, fad7, constructed in pBI121 was coated onto tungsten particles ($1.1{\mu}m$) and introduced into callus cells by bombarding with 1100 psi of helium pressure, 1/4 in of gap distance, 7.0 cm of target distance and 27 in Hg of chamber vacuum. The bombarded cells were selected on the medium containing kanamycin. The selected cells were successfully regenerated into plantlets via somatic embryogenesis on the media containing plant growth regulators. The results of polymerase chain reaction analysis of genomic DNAs from the putative transformants showed that the introduced DNAs of fad7 were present in both the selected callus cells and the regenerated plantlets.

• Journal of Plant Biotechnology
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• v.6 no.2
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• pp.69-75
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• 2004

Optimal protocol for efficient genetic transformation has been defined to aid future strategies of genetic engineering in pigeon pea with agronomically important genes. Transgenic pigeonpea plants were successfully produced through Agrobacterium tumefaciens-mediated genetic transformation method using cotyledonary node explants by employing defined culture media. The explants were co-cultivated with A. tumefaciens strain C-58 harboring the binary plasmid, pCAMBIA-1301 [con-ferring $\beta$-glucuronidase(GUS) activity and resistance to hygromycin] and cultured on selection medium (regeneration medium supplemented with hygromycin) to select putatively transformed shoots. The shoots were then rooted on root induction medium and transferred to pots containing sand and soil mixture in the ratio of 1:1. About 22 putative TO transgenic plants have been produced. Stable expression and integration of the transgenes in the putative transgenics were confirmed by GUS assay, PCR and Southern blot hybridization with a transformation efficiency of over 45%. Stable integration and expression of the marker gene has been confirmed in the TO and T1 transgenics through PCR, and Southern hybridization.

• Journal of Plant Biotechnology
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• v.46 no.4
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• pp.323-330
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• 2019

The high expression level of industrial and metabolically important proteins in plants can be achieved by plastid transformation. The CaIA vector, a Capsicum-specific vector harboring aadA (spectinomycin resistance), is a selectable marker controlled by the PsbA promoter, and the terminator is flanked by the trnA and trnI regions of the inverted repeat (IR) region of the plastid. The CaIA vector can introduce foreign genes into the IR region of the plastid genome. The biolistic method was used for chloroplast transformation in Scoparia dulcis with leaf explants followed by antibiotic selection on regeneration medium. Transplastomes were successfully screened, and the transformation efficiency of 3 transgenic lines from 25 bombarded leaf explants was determined. Transplastomic lines were evaluated by PCR and Southern blotting for the confirmation of aadA insertion and its integration into the chloroplast genome. Seeds collected from transplastomes were analyzed on spectinomycin medium with wild types to determine genetic stability. The increased chloroplast transformation efficiency (3 transplastomic lines from 25 bombarded explants) would be useful for expressing therapeutically and industrially important genes in Scoparia dulcis L.

• Journal of Plant Biotechnology
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• v.39 no.4
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• pp.225-234
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• 2012

This report describes recent advances in tissue culture and genetic transformation of commercial Phalaenopsis. Recently, an importance of Phalaenopsis has been increased due to its popularity with beautiful flowers and is widely used for pot plants as well as cut-flower. Its use is rapidly enlarging in worldwide. Thus, demands for the release of new elite cultivars in Phalaenopsis have been increased. During the last several decades, some critical progresses have been made in tissue culture and genetic transformation in Phalaenopsis species. Cooperation with these biotechnological methods are supposed to promote the release of commercial Phalaenopsis cultivars in the near future. Until now, no technical review on tissue culture and genetic transformation in Phalaenopsis has been reported in Korea. Therefore, we inquired the brief history and techniques of tissue culture system in Korea.

• Journal of Plant Biotechnology
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• v.37 no.4
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• pp.357-369
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• 2010

Cymbidium is horticulturally important and has been one of the most commercially successful orchid plants as well as cut flowers around the world including Korea. Up to now, a huge number of elite Cymbidium cultivars have been released on the commercial market via cross-hybridization, mutation and polyploidization breeding techniques. To investigate on breeding system in Cymbidium, we inquired the brief history and techniques of breeding and the current status on Cymbidium breeding in Korea. Also, the general propagation process of elite Cymbidium lines via tissue culture should be presented. However, the slow process of conventional breeding and the lack of useful genes in Cymbidium species delays the introduction of new cultivars to the commercial market. To solve these limitations, efficient regeneration and genetic transformation systems should be established in the improvement of Cymbidium breeding program. During the last several decades, some progress has been made in tissue culture and genetic transformation in Cymbidium species. We review the recent status of tissue culture and genetic transformation systems in Cymbidium plants.

• Proceedings of the Korean Society of Crop Science Conference
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• 2005.04a
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• pp.224-225
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• 2005

• Proceedings of the Korean Society of Crop Science Conference
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• 2003.10a
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• pp.84-85
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• 2003