• Journal of Korean Society of Forest Science
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• v.100 no.2
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• pp.172-177
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• 2011

This study was conducted to establish the optimal condition for in vitro propagation of wild Cynanchum wilfordii. The highest in vitro seed germination rate of 91.6% was obtained from the seed treated with gibberellic acid ($GA_{3}$) (100 ppm) for 24 hours followed by cultured on Woody Plant Medium (WPM) media supplemented with 1.0 mg/L 6-benzyl adenine (BA). The best shoot height obtained (5.2 cm) in medium with 1.0 mg/L $GA_{3}$, but the plants was grown abnormally and eventually died. The highest number (2.4) was shown when shoot were in cultured on the media including 0.1 mg/L BA after 4 weeks. Root induction from shoot obtained in vitro culture was effective on ventilation and without plant growth regulators (PGRs) and root length was highly developed (2 cm) at 0.1 mg/L naphthalene acetic acid (NAA). The highest survival rate (70%) was when plantlet grew pre-ventilation of in vitro condition.

• Journal of Plant Biotechnology
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• v.2 no.1
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• pp.21-24
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• 2000

An efficient method of shoot regeneration of peanut is described. In vitro shoot organogenesis from the callus of cotyledon explants of Arachis hypogaea L. was stimulated by addition of Adenine sulphate (Ads) along with 6 - benzylaminopurine (BAP) and - napthalene acetic acid (NAA). Ads (13 ${\mu}{\textrm}{m}$) had a stimulatory effect on shoot bud differentiation when combined with BAP (13 ${\mu}{\textrm}{m}$) and NAA (2 ${\mu}{\textrm}{m}$). Shoot organogenesis was markedly higher (92%) from callus induced on Ads, BAP and NAA combined media than from those formed by the individual supplementation of Ads or BAP with NAA. The shoots elongated on the media with GA$_3$ (1 ${\mu}{\textrm}{m}$). Elongated plantlets rooted with MS media containing IBA (9 ${\mu}{\textrm}{m}$).

• Preventive Nutrition and Food Science
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• v.16 no.4
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• pp.328-332
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• 2011

After preparation of acetone, ethanol, methanol, and water extracts (10 g/300 mL) of dried persimmon (Diospyros kaki cv. Fuyu) flower-buds, total phenolic contents (TPC), 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity (RSA), 2,2-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) RSA, reducing power (RP), and tyrosinase inhibitory activity of the extracts were evaluated. The methanol extracts produced the highest TPC (113.39 mg gallic acid equivalents/g), DPPH RSA ($IC_{50}=40.25\;{\mu}g/mL$), ABTS RSA ($IC_{50}=58.17\;{\mu}g/mL$) and RP ($IC_{50}=69.43\;{\mu}g/mL$) activities while the water extracts generated the lowest values. The ethanol extract showed the highest tyrosinase inhibitor activity (88.90%) at a concentration of 1 mg/mL. These results indicated that persimmon flower-buds may be a useful source of natural antioxidants.

• Korean Journal Plant Pathology
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• v.14 no.6
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• pp.738-740
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• 1998

Bacterial soft rot was occurred on fruit of pepper that was grown in Chunceon, Kangwon province, Korea. The symptoms began as a small hole at 5 mm diameter, which made injury by a tobacco bud worm (Heliothis assulta). The affected fruit became soft and produced offensive odor. The causal organism was isolated from the diseased fruit and was identified as Erwinia carotovora subsp. carotovora based on the morphological, physiological and biochemical characteristics, and on the results of the Biolog program (Biolog Inc., U. S. A.). E. carotovora subsp. carotovora is the first described bacterium which causes bacterial soft rot on pepper in Korea.

• Journal of Plant Biology
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• v.37 no.1
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• pp.17-25
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• 1994

Two potato (Solanum tuberosum L.) cultivars were transformed by Agrobacterium tumefaciens harboring cauliflower mosaic virus (CaMV) 35S promoter and $\beta$-glucuronidase (GUS) gene. Expression patterns of the CaMV 35S promoter according to tissue types and developmental stages, and genetic stability of GUS gene were investigated in the clonal progenies of transgenic potatoes. Kanamycin-resistant shoot emerged from tuber disc after 4 weeks of culture, and root was induced 6 weeks after culture on the selection medium. Shooting frequency of cvs. Superior and Dejima were 43% and 27%, respectively. Mature transformants and their clonal progenies showed no phenotypical abnormality. GUS activity was expressed primarily at parenchymatous cells of phloem tissue around the vascular cambium in the stem and root, and higher activity was found at the apical meristem of shoot, root and adventious shoot bud. GUS activity was higher at tubers of young explants than at stored tubers. These facts indicate that expression level of the CaMV 35S promoter differed according to tissue types and developmental stages of the organs. The GUS gene was stably inherited to each clonal progeny and normally expressed.

• Journal of Korean Society of Forest Science
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• v.76 no.4
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• pp.370-375
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• 1987

This study was conducted to examine the position effect of axillary buds on shoot multiplication and rooting with 1-year-old seedlings of Quercus acutissima. Shoot multiplication was greatly affected by axillary bud position: Productivity of multiple shoots were decreased in the order of top, mid and basal explants respectively. The best shoot multiplication (mean 6.1 shoots per explant) was obtained on WPM medium containing $1.0mg/{\ell}$ BAP and $0.1mg/{\ell}$ NAA using basal explant after 4-week-culture. Rooting was also greatly influenced by position. Its percentage was increased in the order of top, mid and basal explant respectively. Root initiation was better and more rapid on 1/2MS medium than GD medium. High rooting percentage (100%) was obtained on 1/2MS medium containing $0.2mg/{\ell}$ IBA after 15 days culture. Sucrose concentrations did not effect on rooting. However root development and shoot growth were greatly affected by them. Root was developed shortly on 1-2% levels and shoot growth was getting retarded, whereas both of them did not show significant difference at 3-6% levels. Rotting was decreased on 7-8% levels gradually, but shoot and leaf condition was better than any other concentrations. Survival rate of rooted explants in pot was varied according to the position of explants. Seedlings of top part were survived up to about 50% but most of mid and basal part seedlings did not survive over 4 weeks even in high humidity condition. Seedlings in pots showed normal growth over 10 months but most of them showed the condition of premature leaf shedding.

• Korean Journal of Agricultural Science
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• v.15 no.1
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• pp.15-22
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• 1988

Factors affecting the regeneration, reversion of protoplasts from mycelium of F. velutipes were investigated and the selection of auxotrophic mutants from protoplasts of F. velutipes was performed. PDP medium stabilized with 0.6M sucrose was suitable for the regeneration of protoplasts, and regeneration frequency was 0.47-1.32. The regeneration frequency of protoplasts was increased when nutrients were added to the regeneration medium. Especially, yeast extract was the most effective to regeneration of protoplasts. Regeneration pattern of protoplasts was formation of germ tubes from bud-like cells. 13-18% of monokaryotic strains was appeared from reverted protoplasts. Five of auxotrophic mutants were isolated from strains showed survival frequency of 1.9-16.

• Korean Journal of Medicinal Crop Science
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• v.4 no.3
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• pp.187-192
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• 1996

This study was investigated to know about the stages of flower bud development and the effects of natural and artificial cold treatment on flowering of herbaceous peony. Developing buds of Paeonja lactㅑflora Pall. var. Taebaek were observed since Jun. 17 and peony plants were forced since Nov. 27 in the green house with two weeks interval, and other plants were forced after cold treatment in $5^{\circ}C$ for 1, 2, 4, 6weeks. Differentiation of vegetable part in peony buds was started in early June, and floral part was differentiated in September and their differentiation was continued to shooting in early spring. Buds of peony were sprouted and flowered when it was forced on Dec. 4. Days to shooting were decreased with delay of forcing time from early to late of December, significantly. Two weeks for cold treatment were enough to break dormancy of peony and days to shooting of the cold treated were significantly shorter than the untreated in the same forcing times

• Journal of Korean Society of Forest Science
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• v.66 no.1
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• pp.1-7
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• 1984

This study was undertaken to find out the effects of three kinds of potting media and two sources of explants on the survival and early growth of new plantlets of Poputus alba ${\times}$ P. grandidentata in the greenhouse. The results obtained can be summarized as follows; 1) Among three potting media, Terralite was best for early growth and survival of plantlets. 2) Like humidifier, an intermittent misting system can be effective in keeping relative humidity high for the plantlets. 3) Survival rates over 80% could be obtained if humidity was kept high during the hardening period. 4) During hardening period, the plantlets showed the juvenile characteristics such as smaller leaves, thinner stems, and shorter internodes. 5) There were no differences on morphological characteristics between the plantlets originating from axillary buds and the plantlets originating from multiple shoots while they were growing at the greenhouse. 6) The plantlets originating from bud culture grew normally comparing to regular cuttings.

• Korean Journal of Medicinal Crop Science
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• v.1 no.1
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• pp.63-69
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• 1993

Present experiment were attempted to examine in vitro multiplication throughbud culture of Cornus officinalis. Bud derived shoot formation was established successfully on Murashige and Skoog's medium supplemented with $0.5mg\;/\;{\ell}$ BAP(N-benzyl amino purine). The shoot proliferation increased on the Driver Kuniyuki Walnut medium containing $0.5mg\;/\;{\ell}$ NAA(Napthalene acetic acid) and $0.5mg\;/\;{\ell}$ BAP. Addition of 2,4-D(2,4-Dichlorophenoxy acetic acid) to the media produced excessive callus inducton. IAA(Indole-3-acetic acid) and IBA (Indole-3-bu-tyric acid) enhanced multple shooting, and NAA showed callus induction and multiple shooting. Shoot growth was enhanced supplemented with 3% sucrose, $2g\;/\;{\ell}$ activated charcoal, and 1 / 4MS in organic salts. However, root formation of proliferated shoots was low about 5%