• Korean Journal of Plant Tissue Culture
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• v.22 no.6
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• pp.335-337
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• 1995

The effect of plant growth regulators on proliferation of shoot from stem node culture of Japanese yew (Taxus cuspidata Sieb. et Zucc.) was studied using Quoirin and Lepoivre (1977) medium. Among the cytokinin tested, BAP, kinetin, and thidiazuron at various concentrations had no effect on shoot multiplication However when zeatin at 5$\times$10$^{-5}$ M was added to the medium, an average of 6 shoots were regenerated per explant after 8 weeks of culture. The ratio of rooting ex vitro was remarkably increased up to 34% by dipping the basal end in 0.5 to 1.0% IBA on talc compared with 3% in vitro rooting. Rooted plantlets were acclimated in greenhouse conditions for one month and successfully transplanted to the field.

• Korean Journal of Plant Tissue Culture
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• v.22 no.6
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• pp.307-310
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• 1995

Cotyledon and epicotyl explants of P. aridum and P. zonale formed calli when cultured on MS medium supplemented with 2 mg/L NAA and 0.2 mg/L BA. Calli were subcultured on the same medium Upon transfer to MS medium with 0.1 to 0.5mg/L NAA and 0.25 to 2mg/L BA for P. aridum 0.1 to 0.5mg/L NAA and 1 to 2mg/L BA for P. zonale subcultured calli gave rise to the greatest number of shoots (0.78 shoot for P. aridum and 0.65 shoot per explant for P. zonale, respectively).Most shoots produced roots when cultured on 1/2MS basal medium. The regenerates were transferred to potting soil and grown to materity in a greenhouse.

• Journal of Korean Society of Forest Science
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• v.97 no.4
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• pp.452-457
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• 2008

In order to develop an efficient micropropagation technique effect of plant growth regulators (PGRs) affecting on shoot proliferation from shoot apex in Pyrus ussuriensis was tested. Generally, there was no conspicuous effect on shoot induction by the treatment of PGRs and one or two shoots/explant were induced when cultured on MS medium supplemented with BA and/or BA plus NAA. Both apical shoot necrosis and hyperhydric shoots were observed frequently in multiplied shoots, and callus was formed at the basal part of shoots. About 20% spontaneous rooting was achieved in growing shoots, however the proliferated shoots exhibited poor rooting rate in gelrite supported media. When we tried to ex vitro rooting of the shoot cutting, the shoot cuttings rooted up to 50% with 100 mg/L IBA application. The rooted plantlets grew normally after acclimatization in the greenhouse.

• Journal of Crop Science and Biotechnology
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• v.10 no.3
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• pp.141-146
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• 2007

The roots of Aristolochia elegans Mast.(Aristolochiaceae) are widely used in Mexican traditional medicine as a remedy for scorpion venom. Current experimental evidence supports its purported antidote properties. However, collection from the wilderness has lead to local extinction of natural populations. In order to contribute to species preservation, cultivation, and standardization of morphological and pharmacological properties, a micropropagation method was developed. This includes in-vitro germination of seeds to produce aseptic plantlets, induction of multiple budding, and acclimatization. The treatment with benzylamino purine(10 ${\mu}M$) induced the highest number of buds(3.1 on average) in both types of explants. On the other hand, indolebutyric acid(1.5 ${\mu}M$) caused the highest root index(11.8) per explant. One hundred percent of the micropropagated plantlets developed vigorously after the acclimatization process.

• Journal of Plant Biotechnology
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• v.33 no.4
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• pp.263-270
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• 2006

Pongamia pinnata Pierre is a tree legume, having potential in production of raw material for biodiesel. A protocol for in wk propagation of this plant was standardized using seedling explants. Growth regulators (GR) including gibberellic acid $(GA_3),\;N^6-benzylaminopurine(BA)$, thidiazuron (TDZ), and Adenine sulphate (Ads) were tested for optimum germination of seeds. Removal of seed coat prior to germination, controlled fungal growth partially but enhanced bacterial growth. Antibiotic cefotaxime was ineffective in controlling bacterial contamination. Seedling derived nodal explants and cotyledon nodes with attached cotyledons were excised and cultured for induction of shoots. Optimum sprouting and multiplication of shoot buds were obtained in MS medium supplemented with $8.88{\mu}M$ BA. These buds differentiated and rooted on medium devoid of GR. Optimum growth of Pongamia seedling was obtained in cotton plugged culture vessels. Reculturing of the cotyledon node explants produced more shoots from the same site. This process of removing shoots and reculturing of cotyledon node was followed for eight passages yielding 4 to 8 shoots in each cycle. The shoots (75%) rooted on half strength MS basal medium supplemented with 0.22% charcoal. All plants survived on transfer to soil. This is the first report on in vitro regeneration of Pongamia pinnata. This report demonstrates the possibility of coupling more than one parameter in single experiment to hasten the process of standardization. The process of cycling the nodal explant repeatedly for production of large number of shoots from single meristem may find application in genetic transformation experiments wherein meristems are used for transformation.

• 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 Tissue Culture
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• v.25 no.5
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• pp.305-308
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• 1998

Leaf and petiole explants of kiwifruit were cultured on MT basal medium supplimented with 2,4-D, kinetin, NAA, and BA. Higher organogenic callus formation was observed on the media with NAA + BA than on the media added with 2,4-D + kinetin. Adventitious buds were formed only on media with NAA and BA. Leaf was better explant than petiole. When callus and adventitious buds were subcultured, shoot formation responsed best on medium with 0.1 mg/L NAA + 2.0 mg/L zeatin. When shoots were cultured on medium with 0.5 mg/L IAA + 0.1 mg/L BA after soaking for 1 hr at IBA solution, rooting was more effective than non-IBA treatment. Rooted shoots developed into normal plants.

• Journal of Plant Biotechnology
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• v.7 no.3
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• pp.187-193
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• 2005

A protocol was developed for somatic embryogenesis with 100% induction rate from immature zygotic embryo axes of peanut (Arachis hypogaea L. cv. DRG-12) cultured on MS medium containing $18.09\;{\mu}M$ 2,4-D. The frequency of somatic embryogenesis (31.7%) as well as the number of somatic embryos induced per explant (6.6) decreased when the concentration of 2,4-D was increased to $72.4\;{\mu}M$. Morphologically abnormal somatic embryos were observed at a frequency of 43.3% on MS medium containing $72.4\;{\mu}M$ 2,4-D. Somatic embryos isolated from 30-day-old cultures of immature zygotic embryo axes exhibited precocious germination with varied responses when placed on MS basal medium with 3% sucrose. Maximum shoot induction (80.0%) was observed from somatic embryos isolated from 60-day-old cultures of immature zygotic embryo axes when placed as a clump rather than individually on MS medium supplemented with $26.63\;{\mu}M$ BA and $0.54\;{\mu}M$ NAA. Shoots developed from somatic embryos rooted with higher frequency (93.3%) on Blaydes' medium containing $5.4\;{\mu}M$ NAA.

• Korean Journal of Plant Tissue Culture
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• v.24 no.6
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• pp.341-344
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• 1997

Calli were induced from the cotyledon and the hypocotyl of alfalfa and the callus lines were tested for the resistance to glyphosate in the liquid medium containing 0.01-3.00 mM glyphosate. Some resistant cell lines were selected from the gradual increase of glyphosate concentration and the lines resistant to 10 mM glyphosate were analyzed with EPSPS activity. Vigorous callus proliferation from the cotyledon and the hypocotyl was observed from the MS medium containing 1 mg/L 2,4-D and 0.5 mg/L kinetin. The hypocotyl was thought to be better explant source for callus induction than the cotyledon. $ID_{50}$ (Inhibition Dosage of 50%) to glyphosate was between 0.1 mM and 0.2 mM level. A49-10G and A58-10G cell lines selected as resistant to 10 mM glyphosate had 8.0 and 9.1 fold increased EPSPS activity to those of the control lines, respectively.

• Journal of Plant Biotechnology
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• v.6 no.3
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• pp.193-197
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• 2004

In vitro multiplication of Curculigo orchioides was achieved by direct somatic embryogenesis in young leaf segments. Immature leaf segments of about 0.5 cm in length were cultured on MS medium supplemented with different concentrations of BAP (2-10 $\mu{M}$) or Kin (2-10 $\mu{M}$). Optimum response in terms of per cent cultures responding (89%) and the number of embryos per explant (16) were observed on MS medium supplemented with 8 $\mu$M BAP. The emergence of several somatic embryos on the adaxial side of the leaf segments was observed one month after the culture. Germinated somatic embryos were grown up to about 1.5 cm length before transferring to maturation medium. For maturation, the individual embryos were isolated and transferred to MS medium supplemented with BAP (5 $\mu{M}$) and NAA (0.5 $\mu{M}$). The plantlets emerged from the embryos were transferred to soil containing 1 peat: 1 sand with 90% success. The embryos were formed directly on the leaf segments without any callus phase. Direct regeneration of somatic embryos is important for the conservation of this endangered species, as rare somaclonal variants are likely to arise than from indirect regeneration.