• Journal of Plant Biotechnology
• /
• v.32 no.1
• /
• pp.45-50
• /
• 2005

Virus-free stocks was produced by the combination of the heat treatment of virus infected plant and shoot-tip grafting (STS). To produce virus-free stocks, the plants infected with citrus viruses were used for virus-free stock production using the modified method of STG in thermotherapy at $40^{\circ}C$ for 16 hours in the light, and at $30^{\circ}C$ for 8 hours of darkness for 4 weeks. Trifoliate orange (P. trifoliata) were used as rootstock seedling for STG. Percentages of virus-free stocks against citrus tristeza virus (CTV), satsuma dwarf virus (SDV) and citrus tatter leaf virus (CTLV) were $75.7\%,\;100.0,\%\;82.6\%$ respectively. Shoot tip size for successful STG were as small as possible. Less than $0.3\;\cal{mm}$ of shoot tips gave the hight efficiency of virus free plants but survival rates were low. And, survival rate after shoot-tip culture was analyzed and the rates were dependant on the cultivars; Yuzu cultivar showed the hight survival rate ($74.6\%$) and early satsuma mandarin (Iwasagi) was $13.3\%$ as the lowest cultivar. But citrus trees were not succeed to grown, turned brown, and died.

• Journal of Aquaculture
• /
• v.6 no.3
• /
• pp.159-171
• /
• 1993

The effects of environmental factors (density, light, temperature) and live food on growth and survival rate of zoea and mysis of fleshy shrimp, Penaeus chinensis, were examined. The percent survival rates at the culture densities of 200 and 300 larvae per liter were significantly higher than that of 500 larvae per liter (p< 0.05). The percent survival rates at the culture densities of 100, 200, 300 and 500 larvae per liter were $90.3^{ab},\;95.2^a,\;94.3^a\;and\;86.7^b\%$ (p< 0.05). The effects of light conditions with diatom premix diet showed that continuous light was the best for the survival rate, $96.5\%$. Natural light and continuous darkness showed the survival rates $79.0\%\;and\;4.3\%$, respectively. On the rearing temperature, the survival rates were $97.3\%\;at\;19^{\circ}C\;and\;96.7\%\;at\;22^{\circ}C$ with little difference but the higher temperature resulted in faster growth. The survival rate was $51.6\%;at\;25^{\circ}C$ thus showing significant decrease compared to $19^{\circ}C\;and\;22^{\circ}C$. At this temperature the growth was also suffered. With regard to dietary value of live food, both the best survival rate and the fastest growth were obtained when 6 mixed species of diatom (A. normaii, C. simplex, N closterium, P. tricornutum, S. costatum and T. weissflogii) were provided. When single species was supplied the best survival rate $(82.1\%)$ was obtained with S. costatum, but the other species resulted in much inferior survival rates $(below\;80.0\%)$ and poor growth.

• Korean Journal of Plant Tissue Culture
• /
• v.21 no.2
• /
• pp.85-90
• /
• 1994

Attempts were made to regenerate plants from petiole explane of Forest Pimpinella barchycarpa via repetitive somatic embryogenesis. Effective induction of somatic emb교ogenesis was achieved on both MS and modified $B_{5}\;(mB_{5})$ media containing BA + 2,4-D or BA + 2,4-D + NAA under light condition (16-h photoperiod/day) cultures. The explants exposed to the ligt produced numerous somatic embryos while those kept under the dark did not form any on the same medium. Somatic embryos at different developmental stages were observed to arise within a individual explants. Plantlets could be regenerated on $mB_{5}$ basal medium or $mB_{5}$ containing 0.1 mg/L NAA Secondary adventive embryos were formed on the surface of the somatic embryos. Therefore, repetitive somatic embryogenesis could be achieved by secondary embryogenesis. Although the treatment of 2,4-D or NAA alone was effective in callus formation and growth, but not in induction of somatic embryogenesis. Some explants, cultured on NAA-containing media in darkness, produced only adventive roots. The embryogenic potential was maintained for two years when subcultured to BA and 2,4-D containing media with 5 weeks inteval. Regenerated plantlets were maintained on $mB_{5}$ or MS basal media for 4 to 6 more weeks and transferred to soil of an artificial mixture for acclimation. Most plantlets (more than 97%) survived, and grew without any deformity.

• Korean Journal of Medicinal Crop Science
• /
• v.7 no.3
• /
• pp.155-161
• /
• 1999

This study was carried out to develop the propagation system using in vitro induced- microtubers of yams (Dioscorea alata L.). Effects of kinds of media, mineral composition, sucrose concentration (0, 2, 4, 6, 8, 10%), photoperiod (0, 8, 12, 16, 24h), and growth regulators (NAA, IAA, ZR, JA-Me, ABA) on the development of microtubers, roots, and shoots in nodal stem segment cultures of D. alata L. were evaluated. Microtuberization in nodal stem segment occurred on all the media supplemented with growth regulator and sucrose. Among basic media, 1/2MS medium was the best in microtuber induction. NAA was shown to be the most effective among the growth regulators. Optimal NAA concentration was 1mg/l. The microtuberization was the highest at the concentration of 6% sucrose. When the nodal stem segment were cultured under darkness, the tuberization was increased markedly compared to those cultured under light condition. It was also noticeable that the culture in medium with NAA produced only microtubers and roots, but no shoots, in nodal segments. In this study, the optimal medium composition for microtuberization in nodal stem segment was found to be 1/2MS medium supplemented with 1mg/l NAA and 6% sucrose under dark condition at $25^{\circ}C$.

• Applied Biological Chemistry
• /
• v.27 no.1
• /
• pp.34-39
• /
• 1984

Environmental effects of light. temperature, and pH of culture media on mycelial growth and fruit-body formation of Flammulina velutipes in synthetic media were investigated. Illumination inhibited mycelial growth, but illumination during the latter part of vegetative growth induced primordia formation. The optimum light intensity and exposure time were $100{\sim}1000$ lux and $4{\sim}8$ hours per day, respectively. High intensity of light was injurous, and in darkness primordia developed into very poor fruit-bodies. The optimum temperature was $25^{\circ}C for mycelial growth and $15^{\circ}C$ for fruit-body formation. The optimum pH range for mycelial growth was found to be from 5.0 to 7.0 and for fruit-body formation from 5.0 to 6.0. In low temperature treatments, a temperature of $15^{\circ}C$ was more effective than $5^{\circ}C\;or\;10^{\circ}C$, it took about 12 hours for primordium formation, but at $5^{\circ}C\;or\;10^{\circ}C$ about 48 hours. The most excellent fruit-body formation were produced from the mycelium growth for 7 to 10 days.

• Korean Journal of Plant Tissue Culture
• /
• v.28 no.6
• /
• pp.297-304
• /
• 2001

Scrophularia buergeriana Misrule has been contaminated with various pathogens in condition of field and storage period. This study was carried out for production of multiple stress resistance plant containing disease resistance that CGST gene expressed in transgenic Scrophularia buergeriana Misrule genome. Glutathione S-Transferases (GSTs) detoxify endobiotic and xenobiotic compounds by covalent linking of tripeptide glutathione to hydrophobic substrate. GST enzymes have been identified and characterized in insects, bacteria, and many plant species. A cDNA clone of GST was introduced into Scrophularia buergeriana Miquel by transformation with Agrobacterium tumefaciences. In coporation of the CGST gene into S. buergeriana Misrule was confirmed by PCR analysis of genomic DNA. Influence of exposure to darkness on the regeneration potential and transformation frequence were assessed. The activity of GST in transgenic plants was two times higher than that of non-transgenic plants. As a result of anti-microbe assays, the crude extract protein of transgenic plants showed the antimicrobial effects higher than control plants.

• Journal of Life Science
• /
• v.15 no.3 s.70
• /
• pp.468-473
• /
• 2005

The coastal regions of Yeosu, the South Sea of Korea, has occurred annually the red tide which is caused by potentially ichthyotoxic dinoflagellate C. polykrikoides, with a wide avenue for exchange with oceanic waters and freshwater runoff from Sumjin river. We attempted to examine the variability in response to vertical migration and concentration of extracted DNA/RNA of C. polykrikoides exposed to salinity-stratified waters. The experimental aquarium of the 60 liter was employed to culture C. polykrikoides. One aquarium was supplied with only sea water, the other was consisted of sea water and freshwater. Experiment was conducted for 5 days. In experimental column (mixture of freshwater and sea water), salinity was maintained to 20 at upper and approximately 30 at bottom during the period of this study. The fluctuation with related to dissolved oxygen and pH was similar pattern to both columns. Chlorophyll a was significantly higher value at upper than bottom. During 24h, chlorphyll a on experimental column was extremely high on the top as soon as lighting, compared with control. With elapsed time, the gap between experimental and control columns was a little. In darkness, chlorophyll a was not significantly different between upper and bottom, most cells appeared to randomly distribute on column regardless of water layer. Fluctuation with related to concentration of extracted DNA and RNA based on ratio of absorbance of 260 and 280 nm in experimental column was higher at final day or diel migration than control. These results implied that a large volume of freshwater could be associated with influence of concentration of DNA and RNA, in particular, rapid upward movement caused massive fish kills as soon as sunset.

• Journal of Plant Biotechnology
• /
• v.31 no.3
• /
• pp.239-248
• /
• 2004

This experiment was carried out to confirm that phytochrome regulates anthocyanin bio-synthesis during cell suspension culture system of grape or not. In suspension culture of grape, maximum accumulation of anthocyanin was observed at the stationary phase under continuous white light condition. From mono-chromatic light interruption for 24h at the 4th or 7th day on the suspension cultured cells, the anthocyanin accumulation was highly enhanced at the light interruption at 7th day than 4th day under all monochromatic light treatment. However, the cell growth patterns were not affected by any light treatment. In the darkness, the anthocyanin synthesis was very low but remarkably increased by blue light or red light irradiation. However, the increase of anthocyanin accumulation by blue or red light was suppressed by far-red light in the suspension cells of grape. This suppression by far-red light on the anthocyanin synthesis also observed on the cells treated red or far-red light alternatively. These results implied that phytochrome regulation system may be involved in the anthocyanin biosynthesis of the suspension grape cells. By RNA expression analysis, chalcone synthase (CHS) gene was expressed highly by blue and red light but low by far-red light. The synergistic increase of CHS gene expression was also observed at the treatment of blue light followed by red for 24h. This result may explain the increase of anthocyanin accumulation in B/R treatment. Although the expression of phytochrome gene (PHYA or PHYB) was not highly increased by all light treatment (blue, red, and far-red light) the expression of both PHYA gene and PHYB gene was increased a little in cells treated red or far-red light. In grape suspension cells, the red light enhanced the anthocyanin synthesis, whereas the far-red light was suppressed. Although it was not confirmed whether or not phytochrome gene is activated in anthocyanin accumulating grape cells, we believed that anthocyanin biosynthesis in grape cells may be regulated under phytochrome signal transduction system.

• Korean Journal of Agricultural Science
• /
• v.9 no.2
• /
• pp.467-483
• /
• 1982

Leaflets of Allium sativum L. (garlic) and leaf scales Allium cepa L. (onion) were cultured on the Murashige and Skoog(MS) medium to study the effects of plant growth regulators, temperature and light on the formation of shoot and root. And also, the potentiality of shoot or root formation of tissues in accordance with the leaf age and the region was discussed. In the experiment with garlic, the formation of shoot and root was more effective on the medium containing $BA\;2mg/{\ell}$ and $NAA\;1mg/{\ell}$ and it occured on the basal region of outer leaflets. The shoot formation was more effective at $20^{\circ}C$ than $28^{\circ}C$ under 16-hour daylength, and it was more effective in darkness than light condition at $28^{\circ}C$. The results of shoot and root formation on the new cloves of garlic harvested in 1982 were similar to those the old cloves of garlic harvested in 1981. In the experiment with leaf seales of onion, when the tissues of dormant leaf scales of onions harvested in 1981 were explanted on the MS medium, a few shoots were formed on the medium containing $BA\;2mg/{\ell}$ and $NAA\;1mg/{\ell}$. In this case,there were no differences on the shoot formation among the age and region of leaflets. On the culture of leaf scales, the shoot was not formed on the leaf scales located at outer or middle region, but it was formed on the medium containing BA accompanied with NAA at inner scales. On the medium complemented with BA alone, the tissues were not differentiated, but on the medium complemented with NAA, the callus was formed from tissues and then the root was formed through the callus.

• Journal of the Korean Institute of Traditional Landscape Architecture
• /
• v.28 no.4
• /
• pp.127-143
• /
• 2010

This research was made on the interpretation of cultural landscape elements which is shown at nature management around Gyeongcheondae managed by Udam Chae Deug-gi, scholar in Joseon dynasty. Naming the nature management and natural features not only reflected on the formation toward the view of nature by the contemporary intellectuals, but influenced on the fashion of garden culture. Udam Chae Deug-gi dwelt in the riverside of Sangju, Kyungbuk as the characteristics of hermitage and managed landscape and had a willing to live a life free from worldly cares. The Gyeongchundae 28 landscapes, which was managed by himself, represent that natural features are named on the basis of neo-confucian principle and loyalty and he imposed symbolic meaning on landscape management by practically translating his aesthetic consciousness to reality; the name of detailed landscape is largely 'loyalty to Ming dynasty and to king's order and loyalty', 'Taoism' and 'Management will of landscape' by the life of metaphor and enjoyment, and symbolizes 'Searching for learning'. In addition, by selecting 10 out of 28 landscapes around Gyeongcheondae, lyrically describing the landscape by representing the change of time, season and the climate which is the scenic term of Great 8 Sosang views in fashion at that time focusing on the place he strolled or enjoyed watching himself; it can be seen that such moves are related with the landscape management in fashion in order to understand microcosmic providence with the change of natural environment. Therefore, Udam Chaedeug-gi is regarded as the neo-confucian view of nature for which any value scholars in Joseon dynasty have to own - 'loyalty' and 'integrity' - he usually emphasized himself to name the natural features and overcome the darkness of society comparing the landscape management around Gyeongchundae he lived a life free from worldly cares to the situation of Joseon dynasty when a transition times between Ming and Chung comes from China.