• Journal of Plant Biotechnology
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• v.30 no.1
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• pp.73-80
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• 2003

Useful Dianthus species were collected and selected from two native and seven foreign species distributed in Gangwon province. For in vitro breeding,. callus was induced from the explants of apical meristem, leaf, stem and the in vitro adventitious shoots on MS basal medium with 2.0 mg/L 2,4-D and 0.5 mg/L BA at 27$^{\circ}C$ under continuous light. After 3 weeks of culture, calli initiated the most highly from the leaf explants of D. chinensis Organogenic calli were able to be selected from the adventitious shoot-derived calli. For shoot regeneration, these organogenic calli were cultured on MS medium with the combination of 0.1 mg/L NAA＋1.0 mg/L BA under continuous light. Multiple shoots were proliferated with low frequency (about 30%) from those adventitious shootderived calli. Also, shoots initiated directly from the adventitious shoot explants without callus formation at high frequency of 52% when cultured on N6 medium containing 0.1 mg/L NAA and 1.0 mg/L BA in D. gratianopol. Multiple shoots and plantlets grew well and rooted on MS medium supplemented with 0.1 mg/L NAA. Regenerants with well-developed roots were transferred to 8-cm pots containing vermiculite at 85% relative humidity and 27$^{\circ}C$ These plantlets were acclimatized in artificial soil mixture and transferred to the greenhouse for flowering with normal phenotypes. M28 Mutant line was selected with white flowers from 0.03M EMS-treated organogenic calli derived from in vitro adventitious shoot explants of D. chinensis and set seeds.

• Journal of Plant Biotechnology
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• v.30 no.4
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• pp.381-385
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• 2003

An efficient method of plant regeneration from Acanthopanax chiisanensis somatic embryos was developed. Cotyledonary somatic embryos were obtained in liquid Murashige and Skoog (MS) medium from embryogenic cell suspension cultures. They were desiccated for 0 to 72 hr and then cultured on MS medium containing NAA, BA, GA$_3$, (0-0.5mg/L). The highest multiple shoots formation (100％) was obtained from 72 hr desiccated somatic embryos on ifs medium with 0.5mg/L NAA＋0.5mg/L BA or 0.5 mg/L NAA＋0.5mg/L BA＋0.5mg/L GA$_3$ after 6 weeks culture. Plant conversion from multiple shoots was not high. The highest plant conversion from multiple shoots was obtained on 1/3MS medium with 1.0mg/L GA$_3$. Converted plantlets were transferred to ex vitro condition and the highest survival rate (70％) of the plantlets was obtained on plastic pots containing vermiculite and sand. These results indicate that micropropagation procedure can be applied for an efficient mass propagation of Acanthopanax chiisanensis.

• Korean Journal of Weed Science
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• v.18 no.3
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• pp.191-196
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• 1998

This experiment was conducted to investigate the mulch effect of rice straw and dead water foxtail treated with herbicides on weed germination, seedling establishment, and early growth of rice under the no-till culture condition. The percent seedling establishment of rice straw + dead water foxtail mulch was decreased significantly compared to rice straw mulch and non-mulch. Rice straw mulch and rice straw + dead water foxtail mulch inhibited the early growth of no-till direct seeded rice remarkably. However, they promoted rice growth after active tillering stage. Rice straw mulch and rice straw+dead water foxtail mulch in no-till direct seeding decreased weed occurrence significantly. The control value of barnyardgrass, compared with non-mulch, was 96.5% in the rice straw mulch and 75.6% in the rice straw + dead water foxtail mulch, respectively. The pH and concentration of dissolved oxygen in irrigated water were reduced significantly by both rice straw mulch and rice straw+dead water foxtail mulch during early rice growth stage.

• Korean Journal of Environmental Agriculture
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• v.19 no.1
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• pp.1-5
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• 2000

This study was conducted to investigate the growth characteristics of four barley cultivars to NaCl stress of 100mM on 10 March (Tillering stage) and 10 April(Panicle formation stage). Plant grown in Wagner pot(1/5,000 a) with sand culture. Plant height, root length, leaf number and tillering number reduced by NaCl stress and tillering number was shorter than any other character. The reduction of those with NaCl treatment was more severe in 10 March treatment compared to in 10 April it. Leaf, root and straw weight were decreased with NaCl treatment and root weight was more sensitive than any others on 10 March and 10 April treatment. One hundred grain weight (g) in grain component was the most severe in 10 March treatment and panicle number per plant was the most severe in 10 April treatment. The result also varied depending on the cultivars and the time of NaCl stress. In terms of yield component, salt sensitivity was low in order of Bunong, Chalssalbori, Dongbori 1, and Neulssalbori in 10 March and Neulssalbori, Dongbori 1, Bunong and Chalssalbori in 10 April treatment by 100mM NaCl.

• Journal of Bio-Environment Control
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• v.12 no.3
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• pp.166-172
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• 2003

Rockwool slabs used for hydroponic cultures are expected to have potential to be reused after breakdown as a growing medium component for hydroponic culture of vegetables and cut flowers, pot plants, or plug plants. This study was conducted to test the feasibility of using particles of used rockwool slabs (PURS) mixed with woodchips for growing plug seedlings of ‘Nokkufang’ pepper. In the first experiment growth of pepper seedlings was tested in media of steam sterilized PURS mixed with chestnut woodchips (CW), which was weatherized for six months and screened through 2.8 mm or 5.6 mm sieves, at 100:0, 75:25, 50:50, 28:75 or 0:100 (%, v/v). In the second experiment growth of pepper seedlings was tested in 20 different media containing steam sterilized PURS mixed with 4 mm chestnut woodchips (CW), 4 mm pinc woodchips (PW), coir, peatmoss, or perlite. In the first experiment, there were no significant growth differences as affectcd by particle size of CW, while the overall best growth was achieved il1 the control and l00% PURS. In the second experiment, seedling growth was enhanced as compared to the control in 100% PURS or PURS mixed with peatmoss, coir, or perlite. In contrast, growth was suppressed as the proportion of peatmoss or coir mixed with PURS decreased and the proportion of CW increased. Growth was better in the PURS + peatmoss than in the 100% PURS or PURS + coir, and when woodchips were mixed with coir than peatmoss.

• Journal of Bio-Environment Control
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• v.11 no.4
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• pp.157-162
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• 2002

The efficient timer-controlled irrigation and the favorable fruiting position were investigated far highly quality melon fruits from Feb.18 to July Si 1999. The nutrient solution was supplied either at every hour from 6：00 to 18：00 (T-1) or at 6：00, 8：00, 10：00, 11：00, 12：00, 12：30, 13：00, 13：30, 14：00, 14：30, IS：00,16：00, and 17：00 (T-2). A fruit was set at the first node of the fruit bearing branch from the 10, 12, or 13th node of the main stem. Pot weight was maintained at almost n constant level, regardless of the daily integrated solar radiation in T-2. Soluble solids content (SSC) and fresh weight of fruit were not significantly different among the irrigation treatments at each harvesting time. At the first harvest, SSC and fresh weight of fruit were not significantly different between the fruiting positions within the irrigation treatment. At the second harvest, SSC was higher in T-2 than T-1. The SSC was low in the fruit of the loth node in T-1, while it was not significantly different between fruiting positions in T-2. Fruit fresh weight was the highest at the 12 and 13th nodes in T-1, and the 13th node in T-2. Fresh and dry weights of leaf except petiole, regardless of harvesting time, increased as the node position was higher, The higher the fruiting position was, the lower the leaf weight was. Therefore, it is recommended to irrigate more frequently during the mid-noon. Fruits can be harvested earlier at the lower nodes in the spring crop production.

• Journal of Ginseng Research
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• v.40 no.4
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• pp.315-324
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• 2016

Background: Biocontrol agents are regarded as promising and environmental friendly approaches as agrochemicals for phytodiseases that cause serious environmental and health problems. Trichoderma species have been widely used in suppression of soil-borne pathogens. In this study, an endophytic fungus, Trichoderma gamsii YIM PH30019, from healthy Panax notoginseng root was investigated for its biocontrol potential. Methods: In vitro detached healthy roots, and pot and field experiments were used to investigate the pathogenicity and biocontrol efficacy of T. gamsii YIM PH30019 to the host plant. The antagonistic mechanisms against test phytopathogens were analyzed using dual culture, scanning electron microscopy, and volatile organic compounds (VOCs). Tolerance to chemical fertilizers was also tested in a series of concentrations. Results: The results indicated that T. gamsii YIM PH30019 was nonpathogenic to the host, presented appreciable biocontrol efficacy, and could tolerate chemical fertilizer concentrations of up to 20%. T. gamsii YIM PH30019 displayed antagonistic activities against the pathogenic fungi of P. notoginseng via production of VOCs. On the basis of gas chromatography-mass spectrometry, VOCs were identified as dimethyl disulfide, dibenzofuran, methanethiol, ketones, etc., which are effective ingredients for antagonistic activity. T. gamsii YIM PH30019 was able to improve the seedlings' emergence and protect P. notoginseng plants from soil-borne disease in the continuous cropping field tests. Conclusion: The results suggest that the endophytic fungus T. gamsii YIM PH30019 may have a good potential as a biological control agent against notoginseng phytodiseases and can provide a clue to further illuminate the interactions between Trichoderma and phytopathogens.

• Journal of Life Science
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• v.6 no.1
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• pp.40-47
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• 1996

Experiments were conducted to determine the effects of plant growth regulators on in vitro flowering and micropropagation of Gentiana scabra Bunge which had been used the cut flower, pot flower ornamental and medicinal plants. Flower bud formation was affected by GA$_{3}$ and kinetin. The optimum concentrations for flower bud formation was observed at 0.5 mg/l kinetin and GA$_{3}$ , while kinetin was favorable. More flowerings result from the interaction of GA$_{3}$ and kinetin at in a combination of 0.1 mg/l kinetin + o.1 mg/l GA$_{3}$, but the optimum concentration of GA$_{3}$ and kinetin was decreased. All concentrations of kinetin with 0.1 mg/l GA$_{3}$ or O mg/l GA$_{3}$ + 0.5 mg/l kientin reduced t (weeks needed for 50% plantlets). The plantlet growth was affected by GA$_{3}$ and kinetin during plantlet culture. More lateral shots and better shoot length per plantlet were obtained as GA$_{3}$ and kinetin concentration were increased up to 1.0 mg/l. The number of per plantlet was greater increased in MS medium containing GA$_{3}$ than kinetin. Interaction was exhibited at lower concentration with 0.5mg/l GA$_{3}$ and kinetin, but not in higher concentration with 1.0 mg/l GA$_{3}$ and kinetin. Higher pod diameter increased seed germination, while lower pod diameter was obtained from abnormal plantlet. MA medium containing 0.5 mg/l GA$_{3}$ significantly increased germination without regard to pod diameter.

• Journal of Ginseng Research
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• v.40 no.1
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• pp.38-46
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• 2016

Background: Blind and excessive application of fertilizers was found during the cultivation of Panax notoginseng in fields, as well as increase in root rot disease incidence. Methods: Both "3414" application and orthogonal test designs were performed at Shilin county, Yunnan province, China, for NPK (nitrogen, phosphorus, and potassium) and mineral fertilizers, respectively. The data were used to construct the one-, two-, and three-factor quadratic regression models. The effect of fertilizer deficiency on root yield loss was also analyzed to confirm the result predicted by these models. A pot culture experiment was performed to observe the incidence rate of root rot disease and to obtain the best range in which the highest yield of root and saponins could be realized. Results: The best application strategy for NPK fertilizer was $0kg/667m^2$, $17.01kg/667m^2$, and $56.87kg/667m^2$, respectively, which can produce the highest root yield of 1,861.90 g (dried root of 100 plants). For mineral fertilizers, calcium and magnesium fertilizers had a significant and positive effect on root yield and the content of four active saponins, respectively. The severity of root rot disease increased with the increase in soil moisture. The best range of soil moisture varied from 0.56 FC (field capacity of water) to 0.59 FC, when the highest yield of root and saponins could be realized as well as the lower incidence rate of root disease. Conclusion: These results indicate that the amount of nitrogen fertilizer used in these fields is excessive and that of potassium fertilizer is deficient. Higher soil moisture is an important factor that increases the severity of the root rot disease.

• KOMUNHWA
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• no.70
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• pp.35-62
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• 2007

Songguk-ri site gained academic recognition by the excavation of stone coffin tomb with a bronze dagger in 1974. And it is confirmed that this site is epoch-making in Korean bronze age through the following excavation started in 1975. But the excavation reports published until now do not have even overall view of this site, thus it is difficult to get the whole picture of this site. Thus, in this paper the author reexamined all reports on this site and by making the map of overall view and distribution of archaeological features as a basic research. Moreover, I analyzed also artifacts from this site, and compared with the recent papers written by other researchers about the chronology and character. Songguk-ri site has livelihood domain which consists of dwelling pits, attached features, storage pits, pot-firing features, wood fence, abatises, buildings above ground, as well as cemetery which consists of stone-coffins, jar-coffins, pit tombs. Trace of making large terrace was also excavated. These features seem to belong to the same archaeological stage, dated about B.C.850-550, according to C14 dating. On the other hand, the intensification of wet-rice cultivation made this group more productive. Based on this financial strength, some influential group emerged they constructed defensive settlement to protect their products safely. Besides it seems that there were frequent occurrence of conflicts. However, we can know that they kept their stable life, through the expansion of living space. Consequently, Songguk-ri site played a role of the summit among some settlement in this area.