• Korean Journal of Agricultural Science
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• v.14 no.2
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• pp.205-212
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• 1987

To examine the morphogenetic response, stem segments of 8 Populus spp. and 3 different explants of P. nigra var. italica were cultured on MS (Murashige and Skoog 1962) and WPM (Woody Plant Medium) medium containing various phytohormones. The results obtained were as follows: 1. Shoot regeneration and development from stem segment of 8 Populus spp. showed a quite difference according to the section and the species. All of the species of Leuce and Tacamahaca section did not form adventitious buds, while most of explants showed axillary or dormant bud elongation after 4 weeks. But P. nigra var. italica of Aigeiros section showed a successful adventitious bud formation (mean 5.4 buds per explant). 2. Leaf, petiole, and internode segment of P. nigra var. italica showed a quite differences according to media and ex plants upon the morphogenetic response. Adventitious bud formation from leaf was more abundant and readily initiated on the abaxial side than on the adaxial side. Mean number of 103 adventitious buds per explant was obtained from abaxial side of leaf segment cultured on WPM medium containing $0.2mg/{\ell}$ BAP for 5 weeks. 3. 2,4-D (2,4-dichlorophenoxy acetic acid) supplemented to media appeared to be negative upon the adventitious bud formation of P. nigra var. italica, while it promoted callus formation from all explants. Especially, NAA (${\alpha}$-naphtalene acetic acid) or NAA combination with BAP (6-benzylaminopurine) promoted root regeneration from the all explant of P. nigra var. italica in this study.

• Korean Journal of Plant Tissue Culture
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• v.21 no.3
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• pp.157-160
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• 1994

Culture conditions for high Sequency somatic embryogenesis and plant regeneration in tissue cultures of sweet potato of two Korean cultivars 'Puyojaerae' and 'Yulmi' are described. Shoot apical meristem explants (height 150 $\mu\textrm{m}$; base: 350 $\mu\textrm{m}$) were cultured on MS medium supplemented with 1 mg/L 2,4-D. After 6 weeks of culture, greater than 80% of the survived explants produced embryogenic calli. When transferred onto MS medium with 0.1 mg/L each of 2,4-D and kinetin, the calli gave rise to somatic embryos at frequencies of 71% ('Puyojaerae') and 63% ('Yulmi'), respectively: When somatic embryos at various developmental stages measured in length were transversely cut into two halves and cultured on MS medium with 1 mg/L 2,L-D, the upper halves produced secondary embryos more frequently than the lower ones, and halves of somatic embryos less than 1 mm in length had a higher competence for secondary embryo formation than longer ones of either cultivar. However 'Puyojaerae' somatic embryo halves showed a higher frequency of secondary embryo formation than 'Yulmi' ones on the whole. Upon transfer onto MS basal medium, most of the primary and secondary somatic embryos underwent development into plantlets. The plantlets were transplanted to potting soil and grown to maturity in a phytotron. The overall results suggest that the shoot apical meristem culture system for somatic embryo formation in sweet potato previously established by us (SABRAOJ 21: 93-101) may be applicable regardless of it genotypes.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.38 no.4
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• pp.366-370
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• 1993

This study was conducted to determine the optimum culture conditions for inducing callus and regenerating plantlets from cultured leaf tissues of Aralia elata. Young leaf tissues(1cm) of A. elata plant were cultured on MS medium supplemented with 2, 4-D and Thidiazuron. Embryogenic callus was induced along the leaf veins, more efficiently on the medium containing 1.0mg /1 Thidiazuron in 4 weeks after culture initiation. Calli were subcultured to proliferate on MS media containing 2, 4-D, Dicamba, Picloram, and Thidiazuron. Callus was better proliferated on the medium containing Dicamba than on the others.. However, callus subcultured on the medium containing Thidiazuron was more embryogenic and light green-colored, of which some showed embryoid-like structure on the surface. Hormone-free medium was more efficient to regenerate plantlets than media supplemented with Kinetin, BA, and Thidiazuron.

• Plant Resources
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• v.4 no.2
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• pp.65-74
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• 2001

Coleus forskohlii Briq, of the family Lamiaceae yields a valuable secondary metabolity known as forskolin which is a labdane diterpenoid.. Coleus forskohlii is the only known source of this compound. Forskolin is used in medicine for the treatment of glaucoma, congestive cardiomyopathy and asthma. Morphogenic callus was induced from young leaves on MS medium augmented with NAA and BA. These calli, when subcultured on MS with KN alone gave rise to shoots. The regenerated shoot developed good root system on MS medium fortified with NAA. The fully grown plantlets were transferred to soil for acclimatization. Coleus plant is mainly infected by a fungi Lasiodiplodia theobromae which causes root rot disease. The fungal culture filterate (ECE) of Lasiodiplodia theobromae, has been used in regeneration media to find the MIC and further to select resistant plants to the pathogen. In the present study 40% ECF in the medium showed maximum inhibition and is there fore considered as the MIC level of Coleus forshohlii. This data could prove to be useful for the future for selecting a resistant C.forskohlii plant against the root disease caused by L. theobromae.

• 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.

• Journal of Plant Biotechnology
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• v.6 no.3
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• pp.199-204
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• 2004

The medicinal value of the genus Cleome justifies bio-technological studies of Cleome rosea, a Brazilian annual species from sandy coastal ecosystems (restinga), which have been submitted to an intense process of antropogenic degradation. In the present work, was analyzed the influence of cytokinins, 6-benzyladenine (BA) and 6-furfurylaminopurine (kinetin) added to the Murashige and Skoog medium (MS), on the proliferation capacity of explants from the stem axis (hypocotyl, node and internode) for a period of five monthly subcultures (150 days). Regardless of the explant sources, plantlet regeneration by direct and indirect organogenesis was observed. The largest number of shoots proliferated through direct organogenesis was obtained on medium with 4.4 $\mu{M}$ BA. Also, the highest proliferation capacity through indirect organogenesis was found on medium with 4.4 $\mu{M}$ BA + 4.6 $\mu{M}$ kinetin. The presence of kinetin alone was not effective for multiplication of the species. Elongation and rooting were obtained when shoots were transferred onto growth regulator-free medium, and acclimatization rates from 70% to 81% were achieved depending on explant sources used. Plants were then successfully established in soil and showed normal phenotypes.

• Plant Biotechnology Reports
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• v.3 no.4
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• pp.341-345
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• 2009

This study describes culture conditions for a plant regeneration system via a combined pathway of somatic embryogenesis and organogenesis in root explant cultures of the commercial rose cultivar 'Charming'. Root explants formed white calluses at a frequency of 30% after 6 weeks of culture on Schenk and Hildebrandt (SH) medium supplemented with $11mg\;1^{-1}$ 2,4-dichlorophenoxyacetic acid. After 6 weeks of transfer to SH medium without growth regulators, initial white calluses gave rise to globular somatic embryos at a frequency of 2.8%, which were subsequently dedifferentiated to embryonic tissues. Somatic embryos or embryonic tissues initially derived from root explants did not undergo development beyond cotyledonary stage. To produce adventitious shoots, embryonic tissues were sliced and cultured on SH medium with $0.5mg\;1^{-1}$ 6-benzyladenine. After 4 weeks of culture, 28% of embryonic tissue explants formed adventitious shoots. Regenerated shoots were rooted on half strength SH medium with $0.1mg\;1^{-1}$ ${\alpha}-naphthalaneacetic$ acid and subsequently grown to maturity. Root-derived embryonic tissues were proliferated by subculture, while retaining the capacity for shoot production for a few years.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2000.10a
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• pp.96-113
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• 2000

Coleus forskohlii Briq. of the family Lamiaceae yields a valuable secondary metabolite known as forskolin which is a labdane diterpenoid. Coleus forskohlii is the only known source of this compound. Forskolin is used in medicine for the treatment of glaucoma, congestive cardiomyopathy and asthma. Morphogenic callus was induced from young leaves on MS medium augmented with NAA and BA. These calli, when subcultured on MS with KN alone gave rise to shoots. The regenerated shoot developed good root system on MS medium fortified with NAA. The fully grown plantlets were transferred to soil for acclimatization. Coleus plant is mainly infected by a fungi Lasiodiplodia theobromae which causes root of disease. The fungal culture filterate (FCF) of Lasiodiplodia theobromae, has been used in regeneration media to find the MIC and further to select resistant plants to the pathogen. In the present study 40% FCF in the medium showed maximum inhibition and is there fore considered as the MIC level of Coleus forskohlii. This data could prove to be useful for the future for selecting a resistant C,forskohlii plant against the root disease caused by L.theobromae.

• Journal of Ginseng Research
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• v.23 no.3 s.55
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• pp.148-163
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• 1999

The efficacy of three auxins, viz. 2,4-0, NAA and dicamba, were compared for the induction of somatic embryogenesis in American ginseng (Panax quinquefolium L.). Somatic embryos (SEs) formed on ginseng cotyledonary, zygotic embryo and shoot explants after 8 weeks of induction by the auxin stimuli. Significantly more somatic embryos were induced by culture of any of the ginseng explants on media supplemented with $5{\mu}M$ 2,4-0 than any other auxin treatment. Shoots derived from somatic embryos had the greatest regenerative potential and zygotic embryos the least. Explants generated from green (unstratified) seeds gave similar or higher frequency of embryogenesis as the explants derived from stratified seeds. Histological and SEM studies confirmed that the regenerimts were somatic embryos. Somatic embryos germinated and developed into normal plants in $3\~6$ months. About $10\%$ of plantlets from second generation SEs formed flowers within 10 weeks, particularly on media supplemented with $GA_3$ The development of a regeneration system for ginseng through somatic embryogenesis is a necessary first step for mass propagation and genetic improvement of American ginseng.

• Journal of Plant Biotechnology
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• v.36 no.1
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• pp.18-22
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• 2009

This work was conducted to establish an efficient plant regeneration system for genetic transformation and the in vitro conservation of Sedum sarmentosum genetic resources. Effects of glutamine and $AgNO_3$ on plant regeneration between two genotypes were investigated using MS media supplemented with 0.2 mg/L NM and 3.0 mg/L BA. Calluses were formed on leaf explants placed on MS solid media supplemented with 3 mg/L 2,4-D and 1 mg/L BA. Calluses of Keumsan local strain produced shoots at a frequency of up to 100% after 50 days of culture on medium supplemented with glutamine. The highest number of shoots per callus was 17.6 at 350 mg/L glutamine. However, calluses of Wanju local strain gave rise to no shoots under the same culture conditions. Likewise, calluses of Keumsan local strain produced shoots at a frequency of up to 100% after 50 days of culture on medium supplemented with $AgNO_3$ whereas Wanju local strain sporadically produced shoots. The highest number of shoots per callus of Keumsan local stain was 16.1 at $15{\mu}M$ $AgNO_3$. Regenerated shoots were subcultured on hormone-free MS medium for rooting and shoot growth, and then 3-5 cm high plantlets were transplanted to the artificial soils comprising vermiculite and perlite, where they survived at a frequency of 88-100%. After being transplanted into upland soil:sand (1:1, v/v) in a greenhouse, regenerated plants showed a morphologically normal growth.