• KOREAN JOURNAL OF CROP SCIENCE
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• v.26 no.4
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• pp.344-349
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• 1981

This study was conducted to define the effect of 2.4-D, NAA, Benzyladenine, and basic mediums on the callus induction and the organ differentiation from the meristem tips and the stem and leaf segments of the potato. Benzyladenine promoted the induction and growth of shoot from the meristem tip of potato but inhibited initiation of roots and induction of callus. At higher concentration of NAA than 0.5 ppm and of 2.4-D than 1.0 ppm the shoots were not initiated but the callus was induced from the meristem. The callus growth was significantly promoted on the medium containing NAA than 2.4-0. The initiation and growth of the shoots from the potato meristem was significantly increased in the medium containing 2.4-D and BA, or NAA and BA, compared with those containing BA, NAA or 2.4-D alone. The callus was more easily induced from the stem segments than the leaf segments of potato. And the 2.4-D was more effective for the induction and growth of the callus than the NAA. MS medium diluted its concentration to 1/2 was more suitable for the initiation and growth of the shoots from the potato meristem than the MS standard medium. For the initiation and growth of the shoots from the potato meristem, the most desirable medium was the diluted MS medium containing 1.0 ppm BA and 0.1 ppm NAA or 0.1 ppm 2.4-D.

• Horticultural Science & Technology
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• v.34 no.3
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• pp.461-471
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• 2016

This study was conducted to establish an in vitro propagation system for sea-milkwort (Glaux maritima L.), which is an endangered coastal plant species with high horticultural value. Two phenotypes, 'Red type (RT)' and 'Pistachio type (PT)' based on the colors of stem and flower, were obtained from a personal horticulturist in 2009 and used for this study as plant materials. The stock plants showed typical morphologies in flower, capsule, and seed appearances as previously reported. Low temperature treatment at $4^{\circ}C$ for four or more weeks after in vitro sowing maximized seed germination percentage, indicating that imbibition of seed and subsequent low temperature treatment are crucial for its germination. The in vitro seedlings had phenotypic variation, falling into 'RT' and 'PT' classes like the stock plants. Although slight differences depending on genotype and medium were recognized, the fourth or fifth nodes detached from the in vitro seedlings revealed the best multiplication efficacy when estimated on the basis of total number of nodes of newly developed axillary shoots. In addition, the nodes from 'RT' and 'PT' regenerated the most shoots on medium supplemented with $0.5mg{\cdot}L^{-1}$ BA alone and $0.5mg{\cdot}L^{-1}$ BA plus $0.5mg{\cdot}L^{-1}$ IAA, respectively. The node culture-derived plantlets were well acclimatized in a culture room ex vitro and completed the pseudo-annual life cycle coincident with that in the natural salt march habitat with the current cultivation method of applying fresh water-irrigation under an inland environment. This work represents the first report of in vitro propagation of sea-milkwort. Thus, our study will contribute to exo-habitat conservation and natural habitat restoration of this endangered species in addition to development of a horticultural product.

• Journal of Korean Society of Forest Science
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• v.84 no.1
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• pp.41-47
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• 1995

A micropropagation system for black Locust(Robinia pseudoacacia) was established by using shoots and pin-punctured leaves of in vitro germinated seedlings. The greatest number of shoots (an average of 10.5 shoots) was obtained when shoot tips were cultured on MS medium supplemented with 1.0 mg/l BAP and 0.01 mg/l NAA. When pin-punctured leaf explants were cultured on the same medium, mean number of 13.5 shoots were produced. Shoot growth was accelerated by adding 50 mg/l of silver nitrate ($AgNO_3$), an anti-ethylene compound to the culture medium. Each shoot was excised from the mass and transferred onto half strength MS medium for rooting. Zygotic embryos at different developmental stages were cultured on LS medium supplemented with various growth regulators to induce somatic embryos. When cultured on LS medium with 1.0 mg/l 2,4-D. 14.3% of the zygotic embryos induced somatic embryos. Upon transfer onto the basal medium, somatic embryos sporadically converted into plantlets.

• Proceedings of the Botanical Society of Korea Conference
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• 1987.07a
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• pp.357-389
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• 1987

In an attempt to clarify the physiological functions of individual isoperoxidases, we have studied enzymatic and immunological properties as well as cellular distribution of isoperoxidases from tobacco callus and Korean radish. The gene expression patterns of isoperoxidases in shoot and non-shoot-forming tobbaco callus were also examined by rabbit reticulocyte lysatein vitro translation system. These results indicate that fraction of translatable poly(A)-isoperoxidase mRNA was increased considerably in shoots. At the present time, at least 6-7 isoperoxidases could be detected from the translation mixture of total cellular RNA, among which only one cell wall localized anodic isoperoxidase (named A3) mRNA was bimorphic mRNA. These data suggest the possible regulation of peroxidase activity during shoot formation by altering the polyadenylation state of mRNA. In case of Korean radish seedlings, poly(A)- peroxidase mRNA were also increased depending upon aging.

• 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.

• Proceedings of the Botanical Society of Korea Conference
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• 1987.07a
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• pp.213-237
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• 1987

In vitro flowering system may minimize the confounded influence of non-floral meristem parts of plants in studying the relationship of a given treatment and flowering responses. We have induced flower buds from plantlets regenerated from zygotic embryo-derived somatic embryos of ginseng, which circumvented the normal 2-year juvenile period before flowering. The result suggests that the adulthood of ginseng root explants in the experiment previously conducted by Chang and Hsing (1980; Nature 284: 341-342) is not prerequired to flowering of plantlets regenerated through somatic embryogenesis. We have also induced flower buds from elongated axillary brandches from cotyledonary nodes by culturing ginseng zygotic embryos, seedlings, and excised cotyledonary nodes. It was found that 6-benzyladenine (BA) supplemented to the medium was essential for flowering, whereas abscisic acid (ABA) was inhibitory. Gibberellic acid(GA3) was also required for flowering when ABA was present with BA in the medium. The results suggest that cytokinins, gibberellins, and inhibitors play primary, permissive, and preventive roles, respective-ly, in the induction of flowering of ginseng. Tran Thanh Van (1980; Int. Rev. Cytol., Suppl. IIA: 175-194) has developed the "thin cell layer system" in which the induction of shoots, roots, or flower buds from epidermal layer explants were controlled by culture conditions and exogenous growth regulators in the medium, Utilizing the thin cell layer system, Meeks-Wagner et al. (1989; The Plant Cell 1: 25-35) have cloned genes specifically expressed during floral evocation. However, the system is too tedious for obtaining a sufficient amount of plant materials for biochmical and molecular biological studies of flowering. We have developed a garlic callus culture system and one obvious advantaging over the thin cell layer system is that an abundant cells committed to develope into flower buds proliferate. When the above cells were compared by two-dimensional gel electrophoresis with those which have just lost the competence for developing into flower buds, a few putative proteins specific to floral evocation were detected. The garlic callus culture system can be further explored for elucidation of the molecular biological mechanism of floral evocation and morphogenesis.hogenesis.

• Korean Journal of Plant Resources
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• v.36 no.6
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• pp.571-579
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• 2023

In this study, cryopreservation by droplet-vitrification was applied to pear (Pyrus spp.) germplasm. We focused on the development and assessment of various strategies for the selection of suitable tissue, osmoprotection, and dehydration. We also evaluated post-thaw recovery of cryopreserved explants by droplet-vitrification. Preferentially, we tested the effects of preculture and loading treatments to determine which tissues were more suitable, either the apical shoot tips or the axillary buds. Apical shoot tips showed the better regrowth rate than in vitro axillary buds. The most effective techniques for cryopreservation were as follows. Shoots from in vitro seedlings which had been cultured for about 5-6 weeks were cold-hardened at 4℃ for one week, excised shoot tips were precultured on liquid MS medium including 0.3 M sucrose for 31 hours and 0.7 M sucrose for 17 hours, osmoprotected in loading solution (LS) for 40 min, and then cryoprotected in dehydration solution (PVS3) for 90 min. In addition, we found that regrowth rates of explants on regrowth medium after exposure to liquid nitrogen (LN) were higher than those on MS medium. Results indicated that the highest regrowth percentage was 95.6% for 'Bartlett' cultivar and 68.9% for 'BaeYun No.3' cultivar. Consequently, apical shoot tips of two pear cultivars, 'Bartlett' (P. communis) and 'BaeYun No.3' (P. pyrifolia), were successfully cryopreserved by droplet-vitrification. Results of this study show that the enhanced droplet-vitrification method described in the present study could be used as an effective means for long-term storage of pear genetic resources.

• Journal of Plant Biotechnology
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• v.2 no.3
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• pp.151-155
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• 2000

Shoot proliferation was obtained from shoot tips and nodal explants of Vitex negundo L. on MS medium supplemented with either BAP or KIN (0.1-2.0 mg/L) alone or in combination with NAA (0.1 mg/L). The concentrations of cytokinins combined with NAA produced multiple shoots from shoot tips and nodal explants. The highest mean percentage (84.3$\pm$8.0) of shoot multiplication's were observed on nodal explants in the presence of BAP (1.5 mg/L) and NAA (0.1 mg/L) followed by shoot tips (65.0$\pm$5.0). The regenerated shootlets were rooted on MS basal medium IAA, IBA, NAA (0.1-1.5 mg/L). The maximum number of roots (51.0$\pm$2.6) was achieved on the medium containing IBA (1.0 mg/L) followed by other auxins (NAA, IAA). The regenerated plants were successfully transferred to a mixture of vermiculate and soil. About 95% of the plantlets survived when transferred to the field.

• Korean Journal of Medicinal Crop Science
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• v.10 no.4
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• pp.263-268
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• 2002

Acifluorfen-tolerant callus lines of Solanum ptycanthum were isolated by stepwise selection. Growth of the unselected line was completely inhibited at 0.5 uM. while some selected lines grew at 8 uM acifluorfen. Twenty-two of twenty-five acifluorfen-tolerant callus lines regenerated shoots. Many of the regenerated somaclones were variants, differing in leaf shape, leaf color, number of flower parts, flower color, and fertility. The acifluorfen tolerant S. ptycanthum callus lines differed.

• Journal of the Korean Institute of Landscape Architecture
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• v.29 no.4
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• pp.82-90
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• 2001

This study was carried out to reveal optimum conditions for in vitro propagation of 3 Korean native azalea species, Rhododendron mucronulatum, R. yedonese var. poukhanense, and R. shlippenbachii, which are useful for landscape proposes. Seeds and meristems from three azalea species were cultured on 1/2MS, Hyponex, and Anderson media containing growth of regulators benzyladenine(BA) and 2-isopentenyadenosine(2ip). The results were as follows. 1. In the culture of R. schlippenbachii and R. mucronulatum seeds, in vitro seedlings germinated and grew well on he 1/2MS and Anderson media, while R. yedoense var. poukhanense on Hyponex media containing 6.0mg/$\ell$ 2ip. 2. When the meristems of R. mucronulatum were cultured on Andeson media containing 9.0mg/$\ell$ 2ip, the survival rate of meristems was 23.0% in 6 weeks after culture, and the survival rate of R. schlippenbachii was 46.0% o nthe same media containing 12.0mg/$\ell$ 2ip. The survial rate of R. yedoense var. poukhanense was 92.0% onHyponex media containing 0.5mg/$\ell$ BA and 9.0mg/$\ell$ 2ip. When the meristems of R. mucronulatum and R. yedoense var. poukhanense were cultured on Hyponex media containing 12.0mg/$\ell$ 2ip, they showed the most excellent growth. R. schlippenbachii grew well on Anderson media containing 9.0mg/$\ell$ 2ip. When in vitro shoots of R. yedoense var. poukhanense were subcultured to solid medium, they grew well in shoot growth on Hyponex media containing 6.0mg/$\ell$ 2ip.