• Plant Biotechnology Reports
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• v.3 no.3
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• pp.205-211
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• 2009

An efficient in vitro regeneration protocol for moth bean [Vigna aconitifolia (Jacq.) Marechal] via somatic embryogenesis has been developed. Embryogenic callus cultures were established from the cotyledonary node as explant on semi-solid Murashige and Skoog (MS) medium supplemented with $0.75mg\;1^{-1}$ 2,4-dichlorophenoxyacetic acid (2,4-D) and $1.5mg\;1^{-1}$ 6-benzylaminopurine (BA) and with various additives ($50mg\;1^{-1}$ ascorbic acid and $25mg\;1^{-1}$ each of adenine sulphate, citric acid and $_L-arginine$). Numerous somatic embryos differentiated on MS basal nutrient medium supplemented with $0.25mg\;1^{-1}$ 2,4-D and $0.5mg\;1^{-1}$ of kinetin (Kin). Sustained cell division resulted in the formation of cell aggregates, which progressed to the globular- and heart-shaped somatic embryos and then, if they differentiated properly, to the torpedo shape and cotyledonary stages. The transfer of embryos onto fresh MS basal medium containing $0.2mg\;1^{-1}$ BA and $2.0mg\;1^{-1}$ gibberellic acid enabled the embryos to achieve complete maturation and germination. More than 80% of somatic embryos were converted into true-to-type fertile plants. In vitro-regenerated plantlets with well-developed roots were successfully hardened in a greenhouse and established in soil.

• The Journal of Natural Sciences
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• v.4
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• pp.103-142
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• 1991

These studies were carried out to select somatic hybrid using selectable marker genes of Nicotiana glauca transformed by NPTII gene and Solanum tuberosum transformed by T- DNA, and to study characteristics of transformant. The results are summarized as follows. 1. Crown gall tumors and hairy roots were formed on potato tuber disc infected by A. tumefaciens Ach5 and A. rhizogenes ATCC15834. These tumors and roots could be grown on the phytohormone free media. 2. Callus formation from hairy root was prompted on the medium containing 2, 4 D 2mg/I with casein hydrolysate lg/l. 3. The survival ratio of crown gall tumor callus derived from potato increased on the medium containing the activated charcoal 0. 5-2. 0mg/I because of the preventions on the other hand, hairy roots were necrosis on the same medium. 4. Callus derived from hairy root were excellently grown for a short time by suspension culture on liquid medium containing 2, 4-D 2mg/I and casein hydrolysate lg/l. 5. The binary vector pGA643 was mobilized from E. coli MC1000 into wild type Agrobacteriurn tumefaciens Ach5, A. tumefaciens $A_4T$ and disarmed A. tuniefaciens LBA4404 using a triparental mating method with E. ccli HB1O1/pRK2013. Transconjugants were obtained on the minimal media containing tetracycline and kanamycin. pGA643 vectors were confirmed by electrophoresis on 0.7% agarose gel. 6. Kanamycin resistant calli were selected on the media supplemented with 2, 4-D 0.5mg/1 and kanamycin $100\mug$/ml after co- cultivating with tobacco stem explants and A. tumefaciens LBA4404/pGA643, and selected calli propagated on the same medium. 7. The multiple shoots were regenerated from kanamycin resistant calli on the MS medium containing BA 2mg/l. 8. Leaf segments of transformed shoot were able to grow vigorusly on the medium supplemented with high concentration of kanamycin $1000\mug$/ml. 9. Kanamycin resistant shoots were rooting and elongated on medium containing kanamycin $100\mug$/ml, but normal shoot were not. 10. For the production of protoplast from potato calli transformed by T-DNA and mesophyll tissue transformed by NPTII gene, the former was isolated in the enzyme mixture of 2.0% celluase Onozuka R-10, 1.0% dricelase, 1.0% macerozyme. and 0.5M mannitol, the latter was isolated in the enzyme mixture 1.0% Celluase Onozuka R-10, 0.3% macerozyme, and 0.7M mannitol. 11. The optimal concentrationn of mannitol in the enzyme mixture for high protoplast yield was 0.8M at both transformed tobacco mesophyll and potato callus. The viabilities of protoplast were shown above 90%, respectively. 12. Both tobacco mesophyll and potato callus protoplasts were fused by using PEG solution. Cell walls were regenerated on hormone free media supplemented with kanamycin after 5 days, and colonies were observed after 4 weeks culture.

• Journal of Plant Biotechnology
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• v.40 no.1
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• pp.49-54
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• 2013

C3HC4-type RING zinc finger proteins essential in the regulation of plant processes, including responses to abiotic stresses. We previously isolated and examined the C3HC4-type RING zinc finger protein (BrRZFP1) from Brassica rapa under abiotic stresses. To elucidate the role of the BrRZFP1 transcription factor in gene regulation, we transformed tobacco plants with the BrRZFP1 gene. Plants were regenerated from 82 independently transformed callus lines of tobacco and analysed for transgene expression. Transgene integration and expression was confirmed by Southern and RT-PCR analyses, respectively. T2 plants displayed more tolerance to the bacterial pathogens Pectobacterium carotovorum and Ralstonia solanacearum, and the tolerance levels were correlated with BrRZFP1 expression levels. These results suggest that the transcription factor BrRZFP1 is an important determinant of stress response in plants and its overexpression in plants could increase biotic stress resistance.

• Korean Journal Plant Pathology
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• v.14 no.5
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• pp.513-518
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• 1998

Beet curly top virus (BCTV) mutant has been constructed in vitro that contain G-to-T transversions at nucleotide 2727 within overlapping open reading frames (ORFs) L1 and L4. The mutations introduce termination codon in ORF L4 without affecting the amino acid encoded by ORF L1. When agroinoculated into Arabidopsis thaliana the mutant caused mild stunting and stem curling, but not the callus induction and hyperlasia on infected tissues of Sei-O ecotype. However, this mutant was not infectious on Col-O. Levels of single stranded DNA forms were similar in mutant and wild type BCTV infections. The DNA quantitation data showed that the DNA of BCTV-L4 mutant virus was accumulated in shoot tips, infection origin and roots with similar levels to those of wild type virus infected. Three tissues of asymptomatic ecotype Col-O also had as much as virus DNA from wild type virus infections. In both ecotypes infected with BCTV-Logan and BCTV-L4 mutant, root tissues contained more virus DNA than any other tissues by the Southern hybridization data. The results suggest that ORF L4 encodes a functional protein that is a major determinant of pathogenesis that might affect the hyperplastic response of the host to BCTV infection.

• Asian-Australasian Journal of Animal Sciences
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• v.17 no.10
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• pp.1390-1394
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• 2004

We have achieved efficient transformation system for forage-type tall fescue plants by Agrobacterium tumefaciens. Mature seed-derived embryogenic calli were infected and co-cultivated with each of three A. tumefaciens strains, all of which harbored a standard binary vector pIG121Hm encoding the neomycin phosphotransferase II (NPTII), hygromycin phosphotransferase (HPT) and intron-containing $\beta$-glucuronidase (intron-GUS) genes in the T-DNA region. Transformation efficiency was influenced by the A. tumefaciens strain, addition of the phenolic compound acetosyringone and duration of vacuum treatment. Of the three A. tumefaciens strains tested, EHA101/pIG121Hm was found to be most effective followed by GV3101/pIG121Hm and LBA4404/pIG121Hm for transient GUS expression after 3 days co-cultivation. Inclusion of 100 $\mu$M acetosyringone in both the inoculation and co-cultivation media lead to an improvement in transient GUS expression observed in targeted calli. Vacuum treatment during infection of calli with A. tumefaciens strains increased transformation efficiency. The highest stable transformation efficiency of transgenic plants was obtained when mature seed-derived calli infected with A. tumefaciens EHA101/pIG121Hm in the presence of 100 $\mu$M acetosyringone and vacuum treatment for 30 min. Southern blot analysis indicated integration of the transgene into the genome of tall fescue. The transformation system developed in this study would be useful for Agrobacterium-mediated genetic transformation of tall fescue plants with genes of agronomic importance.

• Korean Journal of Plant Resources
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• v.19 no.3
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• pp.427-431
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• 2006

In vitro high-frequency plant regeneration of Muscari comosum var. plumosum through somatic embryogenesis was obtained via two developmental pathways: direct embryos and multiple shoots regenerated from embryogenic callus. Flower bud with pedicel, receptacle, petal and ovary wall, floral stalk and leaf as explants were cultured in MS medium supplemented with various plant growth regulators. Embryos formed directly from pedicel, receptacle and floral stalk. Depending on explant sources, the optimal medium was MS medium supplemented with 0.2 mg/L IBA and 0.3 mg/L BA, 3.0 mg/L IBA and 3.0 mg/L BA, and MS-free medium for pedicel, receptacle, and floral stalk, respectively. Multiple shoots regenerated from embryogenic cal]i which was initiated from petal, ovary and leaf were observed in MS medium with different concentrations and combinations of hormone. The most suitable medium for each type of explant was 3.0 mg/L IBA and 3.0 mg/L BA(petal and ovary) and 5.0 mg/L IBA and 5.0 mg/L BA (leaf) Furthermore, the combination of 0.1 mg/L 2,4-D and 1.0 mg/L BA was also good for all sources of explants not only for direct embryo formation, but also, for embryogenic callus induction.

• Journal of Ginseng Research
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• v.38 no.3
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• pp.220-225
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• 2014

An efficient in vitro protocol has been established for somatic embryogenesis and plantlet conversion of Korean wild ginseng (Panax ginseng Meyer). Wild-type and mutant adventitious roots derived from the ginseng produced calluses on Murashige and Skoog (MS) medium supplemented with 0.5 mg/L 2,4-dichlorophenoxyacetic acid and 0.3 mg/L kinetin; 53.3% of the explants formed callus. Embryogenic callus proliferation and somatic embryo induction occurred on MS medium containing 0.5 mg/L 2,4-dichlorophenoxyacetic acid. The induced somatic embryos further developed to maturity on MS medium with 5 mg/L gibberellic acid, and 85% of them germinated. The germinated embryos were developed to shoots and elongated on MS medium with 5 mg/L gibberellic acid. The shoots developed into plants with well-developed taproots on one-third strength Schenk and Hildebrandt basal medium supplemented with 0.25 mg/L 1-naphthaleneacetic acid. When the plants were transferred to soil, about 30% of the regenerated plants developed into normal plants.

• Journal of Plant Biotechnology
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• v.32 no.4
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• pp.301-306
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• 2005

Conditions for efficient organogenesis and plant regeneration from Dianthus gratianopol suspension cultured cells were established. Shoot-forming calli of glossy surface, pale green and knobby type were selected from leaf explant-derived calli and were suspension-subcultured every week in CP liquid medium with 1.0 mg/L 2,4-D and 0.5 mg/L BAP. Combinations of 1.0 mg/L 2,4-D and 0.5 mg/L BAP, and 1.5 mg/L 2,4-D and 0.5 mg/L BAP were effective for the induction of regenerative callus from the suspension cultured cell clusters. Multiple shoot primordia were initiated from the green spots of these regenerative callus and formed shoots on MS medium with 1.0 mg/L TDZ and 0.5 mg/L PAA. Shoot regeneration frequency (calli regenerating at least one shoot) was about 87%. For plant regeneration, proliferated shoots were excised and transferred to MS medium with 0.1 mg/L NAA for root initiation after 9 weeks of culture. The regenerants were potted in soil and formed the flowering buds and petals. Also, adventitious shoots were formed from the excised green shoot primordia of regenerative callus and these shoots proliferated successfully and regenerated to whole plants.

• Journal of Plant Biotechnology
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• v.30 no.1
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• pp.35-40
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• 2003

In this study we investigated the effect of gametocides on the number of larger-sized pollen in anther, and also induced callus from the anther culture of Zoysia japonica Steud. Before culturing, we have observed pollens in anther through fluorescence and electron microscopes to know pollen dimorphism. There were two types of pollens observed. One type (30-36 ${\mu}{\textrm}{m}$ in diameter) consisted of vacuolated, larger-sized pollens and the other (15-20 ${\mu}{\textrm}{m}$ in diameter) smaller-sized ones with dense cytoplasm and plenty of amyloplasts. Within few hours, all the smaller-sized pollens were dead, while larger-sized ones were viable for one or two days. To induct larger-sized pollens, various gametocides were leaf-sprayed on three booting stages cultured under 4$0^{\circ}C$ /15$^{\circ}C$ (day/night) before anther culturing. Number of these larger pollens were few (less than 1%) in anther without spraying gametocides. GA$_3$increased the number of larger-sized pollens when applied at mid-booting stage. GA$_3$ with 50 mg/L treatment caused the highest percentage (25.4%) of the larger-sized pollen. Anthers with GA$_3$ treatment were only produced calli on AA medium (modified B$_{5}$+8.0 mg/L 2,4-D ＋0.2 mg/L kinetin), but callus formation was quite low (less than 1%).).

• Journal of Species Research
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• v.10 no.1
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• pp.57-62
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• 2021

A new species, Miscanthus wangpicheonensis of section Kariyasua, is described and illustrated from the morphological characteristics based on a type specimen collected from Gyeongsangbuk-do. This new species is similar to Miscanthus sacchariflorus (Maxim.) Hack., and M. longiberbis (Hack.) Nakai. The characters which distinguish the above two species are short leaves and racemes, callus hairs 1-1.5-times longer than spikelet, and well-developed awns of spikelet. The specific epithet, "wangpicheonensis", is based on the name of the locality where the new species is found. We assume this new species originated from the hybridization of Miscanthus sacchariflorus (Maxim.) Hack., and M. longiberbis (Hack.) Nakai. Miscanthus wangpicheonensis is found in only one locality in Uljin-gun, Gyeongsangbuk-do, Republic of Korea.