• Korean Journal of Environmental Agriculture
• /
• v.17 no.4
• /
• pp.346-351
• /
• 1998

To investigate the hormetic effects of the low dose ${\gamma}-ray$ radiation on the germination rate, Welsh onion (Allium fistulosum L. cv. Eunchun and cv. Sukchangwoidae) seeds were irradiated at the dose of $0.5\;{\sim}24.0$ Gy with the ${\gamma}-ray$ radiation (Co-60). The germination rate of 'Eunchun' cultivar increased about 10% in the low dose ${\gamma}-ray$ irradiation group compared with that of the control. In the 'Sukchangwoidae' cultivar, the germination rate of the 4 Gy irradiation group increased 40% more than that of the control. Broadly, it seemed that the hormetic effects of the low-dose ${\gamma}-ray$ radiation were taken more promisingly in the uncultivated soil than in the fertile soil. The germination rate from the paper towel and filter paper based cultivation increased 10% and 16% more, respectively, in the 1 Gy irradiation group than that in the control group. And the electric conductivities of the above groups supposed to be taken hormetic effects of the ${\gamma}-ray$ radiation were lower than those of the control group. From the above results, it is suggested that the low dose ${\gamma}-ray$ radiation ranged from 1 Gy to 10 Gy could have the hormetic effects on the germination rate related characters in Welsh onion seeds.

• Journal of Life Science
• /
• v.19 no.9
• /
• pp.1245-1250
• /
• 2009

Beimu (Fritillaria thunbergii Miquel), a bulbous plant of Liliaceae found in Korea, Japan and China, has been used as an antitussive and expectorant agent, and is also useful in alleviating stonsillitis and bronchiolitis. Most researches have been focused on micro-propagation and plant regeneration, component analysis, and dormancy relieving of beimu. Reports regarding the biological activity of beimu, such as anti-Helicobacter pyroli or platelet aggregation inhibition activity, are few and not widely available. In this study, methanol extract and its organic solvent fractions were prepared from Fritillaria thunbergii Miquel and their antimicrobial, antithrombin, and antioxidant activities were evaluated, respectively. The methanol extract contained lots of water-soluble materials (58.98%) and hexane-soluble oils (14.85%). The ethylacetate and butanol fraction at $500{\mu}g$/disc concentration showed strong antibacterial activity against tested bacteria, except Escherichia coli. Antifungal activity was not observed in methanol extract and its fractions. The hexane, ethylacetate and butanol fractions showed strong antithrombin activity at 4.8 mg/ml concentration. Especially, the ethylacetate fraction showed 95.4 sec of thrombin time at a concentration of 1.2 mg/ml, which is comparable to aspirin, a widely used antithrombosis agent. For antioxidation activity, the ethylacetate and butanol fraction showed good 1,1-diphenyl-2-picryl hydrazyl scavenging activity ($IC_{50}$ of $344{\sim}368{\mu}g$/ml). In superoxide dismutase-like activity and reducing power, the fractions showed $20{\sim}25%$ of vitamin C, and $51{\sim}54%$ of butyl hydroxytoluene, respectively.

• Journal of Korean Society of Forest Science
• /
• v.101 no.2
• /
• pp.291-296
• /
• 2012

Triploids are a useful tool for biomass production and molecular breeding of trees with a long life span. Triploids of the poplar 'Hyunsasi' (Populus alba ${\times}$ P. glandulosa) have been developed by crossing between female diploids and a male tetraploid. The tetraploid was developed around the 1970s at Korea Forest Research Institute by colchicine-induced chromosome doubling. Seedlings of the $F_1$ generation were analyzed using flow cytometry to verify their ploidy status. The mean relative fluorescence index of 3 F1 poplars, labeled as Line- 1, Line-17, Line-18, were approximately 1.5 times higher than those of diploid poplars, and the results clearly indicated that they were triploids. The phenotype of the F1 poplars included larger leaves and thicker stem than diploids, and abnormal leaf morphology, especially in the triploid 'Line-18'. Three triploid lines developed roots more slowly and had less roots than diploid. However, 3 poplar cytotypes (2x, Line-1, Line-17) rooted within 10 days on MS medium. In contrast, compared with the 3 cytotypes, the Line-18 showed about 80% and 70% in the rooting rate and the number of roots. The triploid poplars could be directly utilized for biomass production and with their sterility, they could serve as basic material for genetic transformation. In addition, flow cytometric analysis proved to be an effective and reliable method for screening forest trees for their ploidy level.

• Journal of Plant Biotechnology
• /
• v.46 no.4
• /
• pp.303-309
• /
• 2019

A protocol for the in vitro propagation of Chamaecyparis obtusa was established in the present study. Multi-shoots were initiated from apical shoot explants from germinants after 10 weeks of culture on Litvay medium (LM) supplemented with different concentrations of cytokinin. The effects of pre-treatment with high concentrations of cytokinin and varying concentrations (0.2 to 5.0 mg/L) of zeatin on in vitro shoot elongation and shoot multiplication were investigated. Optimal shoot growth was achieved on LM medium, with over 10-mm shoots after 10 weeks of culture. In the anti-browning tests, ethanesulfonic acid triggered the least browning in the shoot tips. The highest multi-shoot induction was observed in the 0.5-mg/L zeatin treatments, which yielded 80% induction of shoots after 10 weeks of culture, and maximum shoot elongation was observed in the LM basal medium without the hormone. The highest rooting rates were 65% under 0.2 mg/L indole-3-butyric acid.

• Horticultural Science & Technology
• /
• v.35 no.1
• /
• pp.131-141
• /
• 2017

This study was conducted to investigate in vitro mass propagation methods suitable for each growth stage of A. aristata (G. Forst.) Tindale, from spore germination to sporophyte formation. Among spores germinated in $1/8-1{\times}MS$ medium and Knop medium, Knop medium yielded the highest germination percentage (87.1%). We cultured prothalli obtained from germinating spores for 8 weeks on media with different concentrations of sucrose and active carbon, as well as different concentrations and ratios of nitrogen, to select a suitable growth medium. A. aristata (G. Forst.) Tindale prothalli grew most actively in MS medium with 3% sucrose and 20 : 40 mM of $NH_4Cl$ and $KNO_3$ (total concentration of 60 mM). We investigated sporophyte formation according to soil type, finding that bedding soil mixed with perlite at a 2 : 1(v / v) ratio yielded the highest number of sporophytes per pot ($73.8/7.5{\times}7.5cm\;pot$). By contrast, when peat moss was used alone or mixed with other substrates, prothallus development and sporophyte formation were suppressed. Therefore, the most effective propagation method for A. aristata (G. Forst.) Tindale is to grow prothalli in MS medium and to induce sporophyte formation in a mixture of bedding soil and perlite (v / v = 2 : 1).

• Current Research on Agriculture and Life Sciences
• /
• v.2
• /
• pp.15-22
• /
• 1984

This study was conducted to identify the enzyme treatment time, enzyme concentration and plant growth condition for isolation of potato mesopyll, it was also performed to determine the adquate sucrose molarity on purification of protoplasts and to investigate the incubation time, PEG concentration and DMSO effect for potato-petunia protoplast fusion. The results were summarized as follows: The optimal time of incubation in enzyme solution was 3 - 4 hours and high humidity and low light intensity made plants more effective to protoplast releasing enzymes. Our experimental results showed that the pectolyase Y-23 was an ideal agent for isolation from mesophyll cultured in vitro compared with macerozyme. The enzyme solution with 0.5 % macerozyme and 2 % cellulase was very effective and the purity of healthy protoplast was better in 0.4 and 0.5 M sucrose than in others. It was revealed that the rate of potato-petunia fusion according to the incubation time with PEG was effective at 30 min incubation and percentage of protoplast aggregation was increased by high molecular weight and concentration of PEG. Percentage of potato-petunia protoplast heteroplasmic aggregation was increased by 4 to 16 % in PEG 6000 compared with PEG 4000 and PEG 1500. Addition of 5 to 10 % DMSO to the PEG solution increased to the heteroplasmic aggregation of potato-petunia from 2 to 4 %.

• Korean Journal of Breeding Science
• /
• v.42 no.5
• /
• pp.534-539
• /
• 2010

'Hongro' is early-mid maturing cultivar with good quality like 'Tsugaru' and it has not preharvest drop. The CAX1 gene was introduced into Korean apple cultivar 'Hongro' by Agrobacterium tumefaciens LBA4404 harboring pBI121 to obtain transgenic apple with enhanced Ca level. The CAX1 gene playing the role of $H^+/Ca^{2+}$ transporter from Arabidopsis thaliana increases Ca concentration in several plants. Regenerated transgenic lines were confirmed by polymerase chain reaction (PCR) analysis and Southern blot analysis of genomic DNA for the existence of CAX1 gene. Southern blot analysis of 'Hongro' transformants showed that two putative transgenic lines were integrated with CAX1 gene in genomic DNA. The CAX1 comparative expression levels of two transgenic lines were higher than that of non-transformant evaluated by comparative quantification analysis using a real-time PCR. These two lines were multiplied in vitro, and micro-grafted on apple rootstocks 'M.9' in the isolated greenhouse. Since two years after micro-grafting, the fruits came into bearing. Compared to Ca level of the non-transgenic 'Hongro', that of the CAX1 transgenic 'Hongro' in the flesh and leaves was higher.

• Reproductive and Developmental Biology
• /
• v.28 no.1
• /
• pp.21-27
• /
• 2004

This study was conducted to investigate the developmental ability of caprine embryos after somatic cell interspecies nuclear transfer. Recipient bovine and porcine oocytes were obtained from slaughterhouse and were matured in vitro according to established protocols. Donor cells were obtained from an ear-skin biopsy of a caprine, digested with 0.25% trypsin-EDTA in PBS and primary fibroblast cultures were established in TCM-199 with 10% FBS. The matured oocytes were dipped in D-PBS plus 10% FBS ＋ 7.5 $\mu$ g/ml cytochalasin B and 0.05M sucrose. Enucleation were accomplished by aspirating the first polar body and partial cytoplasm which containing metaphase II chromosomes using a micropipette with an out diameter of 20∼30 $\mu$m. A Single donor cell was individually transferred into the perivitelline space of each enucleated oocyte. The reconstructed oocytes were electric fusion with 0.3M mannitol fusion medium. After the electrofusion, embryos were activated by electric stimulation. Interspecies nuclear transfer embryos with bovine cytoplasts were cultured in TCM-199 medium supplemented with 10% FBS including bovine oviduct epithelial cells for 7∼9 day. And porcine cytoplasts were cultured in NCSU-23 medium supplemented with 10% FBS for 6 ∼8 day at $39^{\circ}C, 5% CO_2 $in air. Interspecies nuclear transfer by recipient bovine oocytes were fused with electric length 1.95 kv/cm and 2.10 kv/cm. There was no significant difference between two electric length in fusion rate(47.7 and 44.6%) and in cleavage rate(41.9 and 54.5%). Using electric length 1.95 kv/cm and 2.10 kv/cm in caprine-porcine NT oocytes, there was also no significant difference between two treatments in fusion rate(51.3 and 46.1%) and in cleavage rate(75.0 and 84.9%). The caprine-bovine NT oocytes fusion rate was lower(P＜0.05) in 1 pulse for 60 $\mu$sec(19.3%), than those from 1 pulse for 30 $\mu$sec(50.8%) and 2 pulse for 30 $\mu$sec(31.0%). The cleavage rate was higher(P＜0.05) in 1 pulse for 30 $\mu$sec(53.3%) and 2 pulse for 30 $\mu$sec(50.0%), than in 1 pulse for 60 $\mu$sec(18.2%). The caprine-porcine NT oocytes fusion rate was 48.1% in 1 pulse for 30 $\mu$sec, 45.2% in 2 pulse for 30 $\mu$sec and 48.6% in 1 pulse for 60 $\mu$sec. The cleavage rate was higher(P＜0.05) in 1 pulse for 30 $\mu$sec(78.4%) and 1 pulse for 60 $\mu$sec(79.4%), than in 2 pulse for 30 $\mu$sec(53.6%). In caprine-bovine NT embryos, the developmental rate of morula and blastocyst stage embryos were 22.6% in interspecies nuclear transfer and 30.6% in parthenotes, which was no significant differed. The developmental rate of morula and blastocyst stage embryos with caprine-porcine NT embryos were lower(P＜0.05) in interspecies nuclear transfer(5.1%) than parthenotes(37.4%).

• Journal of the Society of Disaster Information
• /
• v.8 no.1
• /
• pp.10-17
• /
• 2012

The purpose of this study is to make people acknowledge the danger of the air terror and provide measures to prevent a recurrence of the accident and find required security. Also, the air terror is categorized into aircraft and airport and take steps to come up with preventive measures against the air terror by finding a countermeasure and precaution. The following steps should be checked to take precautionary measures against the air terror. major security crackdown and the need for a further security check should be conducted to prevent terrorists from boarding the aircraft, security around the airport needs to be tightened up by training the airport workers and promoting emergency situations, airport sheriffs and armed guards should be on patrol for the safety of the cabin, new measures of efficient security for in and around the airport and its facilities should be set up to tighten up security of baggage.

• KSBB Journal
• /
• v.14 no.1
• /
• pp.51-57
• /
• 1999

The immobilization of nitrifier consortium was carried out for the application to recirculating aquaculture system(RAS). The abilities of $NH_4^+$-N removal by immobilized nitrifier consortia prepared with boric acid treated, ethanol treated, ad freezing-thawing treated PVA beads at the concentration 15% were examined. To identify the possibility of applying the beads in the fluidized bed reactor, characteristics of beads were evaluated. The suitable bead was boric acid treated beads which had highest ammonia removal rate of 16.09 g/$m^3$/day. It took 12 days for nitrifier consortium immobilized beads to be stable for the removal of $NH_4^+$-N. Life spans of the beads were more than three months with aggressive aeration in the fluidized ed reactor when nitrifier consortia immobilized in PVA beads were used. In order to apply the nitrifier consortium immobilized beads to aquaculture facility, the continuous reactor was used for 49 days with synthetic aquacultural water containing 2 mg/L ammonia. The highest ammonia removal rate of 31.87 g/$m^3$/day was observed when hydraulic residence time was 0.6 hour(36min.).