• Korean Journal of Plant Tissue Culture
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• v.21 no.3
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• pp.161-166
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• 1994

Since garlics (Allium sativum L.) are propagated through cloves, infection by virus or other pathogens may become severe problem if not using high quality seed bulbs every year resulting in the reduction of yield and bulb quality, In order to solve this problem, the establishment of virus-free bulb production and its supply system have been required because no chemicals were found to eliminate viruses from seed bulbs. This experiment was conducted to develop an effective production technique of high quality seed bulbs using shoot-tip culture. Over 90% of shoot-tips explanted on January L 1990 were survived at constant temperature of either 20, 24 or 28$^{\circ}C$, wheres 88% at alternate temperature (28/20$^{\circ}C$). The growth of shoot and root was most vigorous at constant 24$^{\circ}C$, and least at alternate temperature (28/20$^{\circ}C$) condition. When shoot-tips were explanted June 21 to August 1,1991, survival and growth of shoot-tips was most vigorous on MS medium supplymented with 0.1 mg/L NAA and 2 mg/L kinetin and least 1 mg/L Gh$_3$. The shoot-tips taken from the seed bulbs stored at 4$^{\circ}C$ for 15 to 60 days were placed on MS medium, shoot growth and in vitro bulblet formation increased slightly as affected by the increase of told treatment period at 4$^{\circ}C$.

• Journal of Plant Biotechnology
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• v.7 no.4
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• pp.247-257
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• 2005

An efficient, rapid and large-scale in vitro clonal propagation of agronomically important Indian cereal crop genotypes (NSH27 & K5) of Sorghum bicolor (L.) Moench. by enhanced shoot proliferation in shoot tip segments was designed. MS medium fortified with plant growth regulators and coconut water markedly influenced in vitro propagation of Sorghum bicolor. In vitro plantlet production system has been investigated on Murashige and Skoog (MS) medium with the synergistic combination of 6-benzyladenine ($22.2\;{\mu}M$), kinetin ($4.6\;{\mu}M$), adenine sulphate ($2.8\;{\mu}M$), 5% coconut water and 3% sucrose which promoted the maximum number of shoots as well as beneficial shoot length. Subculturing of shoot tip segments on a similar medium enabled continuous production of more than 100 healthy shoots with similar frequency. When the healthy shoot clumps were cultured on MS medium fortified with 6-benzyladenine ($22.2\;{\mu}M$), kinetin ($4.6\;{\mu}M$), adenine sulphate ($2.8\;{\mu}M$), ${\alpha}$-naphthaleneacetic acid ($2.7\;{\mu}M$), ascorbic acid ($30.0\;{\mu}M$) and 5% coconut water, a rapid production of axillary and adventitious buds was developed after 8 wk culture. More than 300 shoots were produced 10 wk after culture. Rooting was highest (100%) on half strength MS medium containing 22.8 mM IAA. Micropropagated plants established in garden soil, farmyard soil and sand (2:1:1) were uniform and identical to the donor plant with respect to growth characteristics. These plants grew normally without showing any traits.

• 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.

• Korean Journal of Plant Tissue Culture
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• v.21 no.4
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• pp.239-246
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• 1994

The genotypic (2n, 3n, 4n) response of watermelon in vitro shoot tip culture was evaluated. Different genotypes had similar response in terms of shoot formation and growth. Shoot formation was better at lower concentration of 0.3 mg/L BA and higher concentration of 5-10.0 mg/L 2iP and kinetin, but growth of newly formed shoot was inhibited. With further subculture, kinetin did not promote shoot formation Better shoot formation was observed at 0.3-0.5 mg/L BA. Combination of 0.3 mg/L BA and 0.3-0.5 mg/L BA was effective in shoot multiplication, growth and induction of more internodes. Varrying levels of light intensity and agar concentration did not affect the performance of tetraploid plants. Higher light intensity and agar concentrations decreased the number of shoot formed in triploid plane. Growth in both genotype, however was inhibited. Higher light intensity was found to promote leaf senescence in all genotypes. All growth inhibitors decreased the number of shoots formed and slowed plant growth there by prolonging duration of cultures. Growth inhibitors were to observed to decrease incidence of hyperhydricity in culture. No difference in shoot formation was observed in each of the concentrations used in Ancymidol, TIBA, CCC and PP333. Shoot formation and growth was more inhibited in ABA treatments. Leaf expansion and growth was poor in all treatments.

• Korean Journal of Plant Resources
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• v.10 no.2
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• pp.114-121
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• 1997

The effects of plant growth regulators on callus formation and organogenesis in shoot tip explant of Belancanda chinensis were examined. Shoot tip explants cultured in full salt strength of MT(Murashige and Tucker) medium containing 2,4-D 1.0 or 2.0mg/l were vigorously formed callus. Full salt strength of MT medium and 1/2 MT medium supplemented with zeatin 1.0mg/l were more effective than that with combination treatments of 2,4-D on the formation of shoots from calli. When shoots regenerated from shoot tips were transplanted into 1/2 MT medium added with 1.0mg/l, 41% of shoots formed roots.

• Korean Journal of Plant Tissue Culture
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• v.22 no.2
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• pp.83-87
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• 1995

Regulation of organ differentiation by growth regulators was investigated through the shoot-tip and bulb-scale cultures of Lilium longiflorum (cv Georgia). When shoot tips were placed on MS medium supplemented with 0.1 mg/L NAA alone or 0.1 mg/L NAA and 0.1 mg/L BA, axillary shoots were proliferated. Root diffentiation and growth were stimulated on the basal medium. Although growth regulation did not seem to be necessary when bulb scales were used as explants for shoot differentiation, its differentiation was promoted vigorously by 0.2 mg/L NAA, but suppressed by BA. Bulblets were formed from bulb-scale-derived plantlets cultured on MS medium supplemented with 0.1 mg/L IBA. And more bulblets were formed from the plantlet in MS medium supplying 0.2 mg/L NAA with 6% than3% sucrose

• Plant Biotechnology Reports
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• v.3 no.4
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• pp.333-340
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• 2009

Developmental anomalies in the plumule meristem of peanut (Arachis hypogaea L.) somatic embryos resulted in poor shoot differentiation and reduced plant recovery. Existing meristems with caulogenic potential have never been tested for embryogenesis in peanut. The present experiment was designed to test the mature zygotic embryo axis derived plumule with three meristems for somatic embryogenesis. Embryogenic masses and embryos developed from the caulogenic meristems in the axils. Exposure of 2 weeks in primary medium with $90.5{\mu}M$ 2,4-D suppressed the shoot tip differentiation temporarily which then regained the ability to form the shoot on withdrawal of 2,4-D. Exposure of 4 weeks in primary medium with $90.5{\mu}M$ 2,4-D suppressed the shoot tip differentiation irreversibly. No shoot formation was noted from the tips in any of the cultures which were in secondary medium with $13.6{\mu}M$ 2,4-D. Development of somatic embryos directly from axillary meristems was confirmed histologically. Conversion frequency of these embryos was 11%. Thus, in this report, we describe a method to obtain somatic embryos from the determined organogenic buds of the axillary meristem, by culturing the nodal explant vertically on embryo induction medium. It also displays the possibility of obtaining both embryogenic and organogenic potential in two parts of the same explant simultaneously. The possibility of extending this approach for genetic transformation in in vivo system through direct DNA delivery or Agrobacterium injection in meristems can also be explored. Using Agrobacterium rhizogenes, we have demonstrated the possibility of gene transfer in the axillary meristems of seed-derived plumule explant.

• Korean Journal of Agricultural and Forest Meteorology
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• v.6 no.3
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• pp.204-209
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• 2004

The main purpose of this study was to select a B. schmidtii population which has high cadmium tolerance and remediation and to determine the difference of cadmium uptake patterns among populations. One-year-old B. schmidtii seedlings were treated with 0, 0.4, 0.8mM CdSO$_4$. 3/8H$_2$O for two months. Cadmium concentrations in different positions of stem and cadmium concentrations and contents of leaves, stems and roots were analyzed. Also soil cadmium concentrations were analyzed. B. schmidtii was highest in root and lowest in shoot tip, showing a gradual decrease from root to shoot tip. The shoot to root Cd concentration ratios were over 1.26. It is concluded that B. schmidtii has good potential for phytoextraction as a shoot accumulator, which can be used for remediation of cadmium-contaminated areas. But tolerance differs between populations. Therefore B. schmidtii should be used as a means of phytoremediation after selection for Cd tolerance is performed.

• Journal of Korean Society of Forest Science
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• v.95 no.5
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• pp.585-590
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• 2006

In vitro-grown axillary shot-tip meristems of Lycium chinense Mill. from cold-acclimated plant were successfully cryopreserved using a vitrification technique. After loading for 15 minutes with a mixture of 2.0 M glycerol and 0.4 M sucrose ($20^{\circ}C$), small segments (1-2 mm, 3-4 mm, and 5-6 mm) were cut from axilary buds and exposed to the cryoprotectant solution containing 30% glycerol, 15% ethylen glycol,15% dimethyl sulfoxide (DMSO), and 0.4 M sucrose at $0^{\circ}C$ for 30-120 minutes prior to direct plunge into liquid nitrogen (LN). After rapid thawing ($40^{\circ}C$), the segments were washed with MS medium containing 1.2 M sucrose for 0-35 minutes, and then transferred onto recovery-growth medium. The highest survival rate (about 90%) was obtained with cold-hardening treatment, and cryopreserved explants were successfully recovered to plantlets. No abnormal morphological changes were observed with the recovered plants after cryopreservation.

• Korean Journal of Plant Resources
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• v.34 no.6
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• pp.600-607
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• 2021

Cryopreservation method using a droplet vitrification was applied to the thirty-one strawberry accessions of in vitro grown shoot tips. A protocol with 0.3 - 0.5 M preculture followed by C4 loading and B1 dehydration solutions efficiently implemented cryopreservation of twenty-six strawberry accessions. The highest regrowth rate was 85.8% for PHS0007 and others were ranged between 85.8% and 21.0%. A slightly modified protocol was applied to five accessions. With these two protocols, twenty-eight accessions obtained more than 40% regrowth rate. This study showed that the droplet vitrification method was able to practically implement cryopreservation of in vitro grown shoot tips of broad range of strawberry germplasm (105).