• Journal of Korean Society of Forest Science
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• 제89권1호
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• pp.105-115
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• 2000

This study was conducted to test a hypothesis that sensitivity of trees to ozone exposure was related to their growth rates. Two cultivars of Populus alba ${\times}$ P. glandulosa with different genetic growth potential were used for the comparison. Two clones(72-30, 72-16) of cultivar No. 4 with fast growing potential and three clones(71-28, 72-27, 72-19) of cultivar No. 2 with slow growing potential were propagated in early spring by cutting in $2-{\ell}$ plastic pots. They were grown outdoor for 5 months and exposed in late August for 30 days to 70 and 130ppb ozone in a open-top chambers(2.5m in diameter and 2m in height). Ozone concentration in a control chamber was maintained below 30ppb by filtering with activated charcoal. Each treatment was replicated twenty times. In a control chamber, cultivar No. 4 grew 73%, 64%, and 38% faster than cultivar No. 2 in leaf weight, root weight, and total dry weight, respectively. Visible injury was observed only in cultivar No. 4 in 130ppb treatment. Ozone treatment at both 70 and 130ppb decreased height growth, dry weight of leaf, root, and entire plants in all five clones. Particularly root growth was reduced by 39.7% and 13.8% in cultivar No. 4 and No. 2, respectively, in 70ppb treatment. Consequently, shoot/root ratio of cultivar No.4 was increased by 63.4%, while that of cultivar No.2 was increased by 22.1%. Stomatal conductance decreased more in cultivar No.4 than in cultivar No.2. Net photosynthesis of cultivar No.4 at 130ppb ozone decreased by 69.5%, while that of cultivar No.2 decreased by 31.5%. Above mentioned physiological responses of two cultivars to ozone strongly suggested that fast growing cultivar No.4 was more sensitive to ozone than slow growing cultivar No.2. It was concluded that sensitivity of trees to ozone exposure was closely related to their growth rates.

• Journal of Food Hygiene and Safety
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• 제16권2호
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• pp.89-95
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• 2001

This study was conducted to find material having antibacterial activity. The effects of preservatives, antibiotics and oriental medicines on growth of teated microorganisms were investigated. The growth of all tested bacteria was inhibited by water extract of Schizandra chinensis. Antibacterial activity on the concentration of Schizandra chinensis extract was tested. The growth of Escherichia coli W3110, Enterobacter colacae MG82 and Salmonella typhimurium was extraordinarily inhibited by more than 0.2% concentration of Schizandra chinensis extract. The specific growth rate of Escherichia coli W3110, Enterobacter cloacae ME82 and Salmonella typhimurium under control conditin had mean values of 0.514(hr￣), 0.381(hr￣) and 0.489(hr￣), respectively. When 0.2% of Schizandra chinensis extract was added, specific growth rates of Escherichia coli W3110, Enterobacter colacae MG82 and Salmonella typhimurium wre decreased, compared to contorl, in 1.26, 2.23 and 1.50 fold, respectivley. Minimal inhibiotory concentration of Schizandra chinensis extract was 0.25% on the tested microorganisms The growth of Enterobacter cloacae MG82 was more inhibited by Schizandra chinensis extract than other tested microorganisms.

• Applied Biological Chemistry
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• 제35권6호
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• pp.443-448
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• 1992

To investigate the production of monoterpenoids by Mentha pipperita cells in suspension culture, effects of media formulation, plant growth hormones, initial pH of the media, and cold stress on the production of essential oil and menthol were analyzed. Among the media employed, Lin-Staba medium resulted in the best essential oil production. Addition of 100 mg/l of yeast extract to the Lin-Staba medium induced the cells to produce large amount of essential oil and high content of menthol (0.39 g/l and 19.6%, respectively). In the effect of plant growth hormone, auxine were more effective than cytokinins. At initial pH of 4.7, oil production was good but menthol content was low. However at pH 5.7 the trend was reversed. When the culture temperature was lowered from $27^{\circ}$ to $10^{\circ}$ during 6 hour-dark period, growth was not changed much but essential oil production and menthol content was increased and reached to 528 mg/l and 21%, respectively.

• Journal of the Korean Society of Tobacco Science
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• 제3권2호
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• pp.109-114
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• 1981

This experiment was conducted with three varieties (Hicks, Burley 21, Sohyang) and cropping systems (Improved mulching, Mulching, Non mulching) of NC 2326 to analyze growth kinetics by means of growth function involving its velocity and accelerated velocity. The basic growth data were obtained by harvest method at interval of ten days from transplanting to hundred days and analyzed by , regression equation, determinant of matrix, and differentiation. The plot of total dry weight of leaves, stalk and roots per a plant vs. time forms a sigmoid curve and its function fitted logistic satisfactorily. Tobacco plant grows at an accelerated velocity. And growth velocity, symmetric about an inflection point, is proportional to biomass attained and to the difference between biomass attained and the maximum, and to the decrease according to the biomass. Of varieties and cropping systems, the most maximum velocity was 9.58g per day per plant in mulching cultivation of NC 2326 and maximum accelerated velocity was 264mg per $day^2$ per plant in Burley 21.

• KOREAN JOURNAL OF CROP SCIENCE
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• 제39권3호
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• pp.262-269
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• 1994

This study was conducted to clarify high yielding factors of F$_1$ hybrids in terms of the growth characteristics, canopy structure, nitrogen content and nitrogen profile in the canopy. Varieties used in this study were four hybrid rices showing different heterosis in grain yield and their parents. Varieties of Japonica were Reimei (maintainer), TP 681 and TP 1278(restorers), and F$_1$ (Reimei ms ${\times}$ TP 681, Reimei ms ${\times}$ TP 1278) hybrid rices. Those of Indica type were 1378 (maintainer), Milyang 46 and Suweon 287(restorers), and F$_1$ (1378 ms ${\times}$ Milyang 46, 1378 ms ${\times}$ Suweon 287) hybrid rices. High heterosis in F$_1$ hybrid rices were shown in panicles per hill and spikelets per panicle, being greatest in spikelets per panicle. Spikelets per square meter expressed even greater heterosis than those two yield components because of multiplicative effect of them. Heterosisof ripened concentration of leaf nitrogen and steeper gradient of leaf nitrogen in canopy strata but also better productive structure in favor of light interception seemed to have led to higher canopy photosynthesis of F$_1$ hybrids and subsequent higher partition of assimilates for leaf area expantion especially during vegetative growth stage. Higher dry matter production, resulting from these factors, during vegetative stage would have contributed to the production of greater number of spikelets per square meter, and consequently to higher grain yield in F$_1$ hybrids.

• Journal of Korean Society of Forest Science
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• 제89권3호
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• pp.452-460
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• 2000

This study was to investigate the growth characteristics, physiological adaptation of Pinus densiflora(Japanese Red Pine) seedlings at the artificial canopy gap in the Quercus acutissima plantation and to analyze its natural regeneration mechanism. Photosynthetic and transpiration rates were analyzed by different levels of photosynthetically active radiation and by seedling growth. Comparing to seedlings at the open area, those at the canopy gap showed more growth in height than in diameter with different levels of light quality and low light intensity, and the increase rate of dry weight was higher in the aboveground than in the underground, maintaining relatively high T/R rate. The C/F(the ratio of non-photosynthetic organs to photosynthetic organs in dry weight) of the aboveground at the canopy gap was higher than that at the open area by 0.1~0.2, while light saturation and light compensation points at the canopy gap were lower than that at the open area by $300{\mu}mol\;m^{-2}s^{-1}$ and 40%, respectively. The seedlings appeared to have shade tolerance to a certain extent at the young growth stage despite Pinus densiflora is typically classified shade-intolerant species. With light intensity lower than $400{\sim}450{\mu}mol\;m^{-2}s^{-1}$, photosynthetic rate and water use efficiency relatively increased by effective use of light energy.

• KOREAN JOURNAL OF CROP SCIENCE
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• 제33권1호
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• pp.59-63
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• 1988

Freshly harvested and depulped Korean ginseng seeds were subjected to the seed treatment of removing endocarp plus surface sterilization with sodium hypocloride, surface sterilization only, and nontreated control. These seeds were stratified at temperatures of 5$^{\circ}$, 10$^{\circ}$, 15$^{\circ}$ and 20$^{\circ}C$ for 20, 40, 60, 80 and 100 days. Embryo growth of the ginseng seeds of which endocarp was removed was most rapid in each stratification temperature and that of sterilized seeds was slower than unsterilized seeds after 80 days stratification at 15$^{\circ}$ and 20$^{\circ}C$. About 15$^{\circ}C$ was an optimal stratification temperature for embry growth in ginseng seeds. Chilling treatment at 5$^{\circ}C$ for 100 days was needed for better germination of dehisced ginseng seeds. An optimal germination temperature for the ginseng seed following chilling treatment was about 15$^{\circ}C$.

• Proceedings of the Korean Society for Bio-Environment Control Conference
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• 한국생물환경조절학회 1998년도 임시총회 및 학술논문발표요지
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• pp.103-106
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• 1998

카네이션에서 적심은 분지수를 늘려 종묘비를 절감하고 개화기를 조절하는데 많이 이용되고 있다. 적심횟수는 1회, 1.5회, 2회의 방법이 있으며 농가에서는 주로 1.5회를 이용하고 있다. 양액재배는 토경재배에 비해 생장속도가 빨라 개화가 빠른 것으로 일반적으로 알려져 있고 양액재배에 적합한 품종 역시 숙기가 빨라 2회 채화가 가능하거나 숙기가 늦은 품종, 절화장이 짧은 품종, 분지력이 좋은 품종이 유리한 것으로 알려지고 있다. (중략)

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 한국농업기계학회 1999년도 하계 학술대회 논문집
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• pp.118-123
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• 1999

화석연료의 연소에 의해 발생되는 질소산화물(NOx)은 가스상의 대기오염물질로서 인류의 생활환경에 유해함은 물론 식물의 생장속도에도 막대한 영향을 미치고 있으며, 질소산화물은 햇빛의 존재 하에서 탄화수소와 광화학 반응을 하여 광화학적 산화물과 오존 등을 생성하는 광화학적 스모그 생성에 관여하고, 이러한 광화학 스모그는 사람에게 만성의 호흡기 질환을 유발하거나 시정거리의 감소를 가져온다. (중략)

• Landscaping Tree
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• 통권108호
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• pp.31-33
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• 2009

화단이나 정원. 공원 등 외부 생활공간의 그늘이나 반 그늘진 곳에 심는 종으로 수호초(秀好草)가 많이 쓰이고 있다. 맥문동과 함께 상록성이면서 키가 크지 않고 심어두면 생장속도가 꽤 빨라 조기에 지면을 덮어주기 때문이다. 특히 우리나라 전역에서 겨울에도 상록으로 월동함으로 사계절 볼거리를 주어 활용범위가 넓은 식물이다. 문헌상 한국에 자생한다고 되어있으나 아직 자생지에서 확인된 경우는 없는 듯 하며 우리나라에 심겨진 것은 대부분 일본에서 들어온 종이 아닌가 싶다. 영명이 Japanese spurge이다. 키가 작아 분화용으로 가능할 것으로 보이지만 반덩굴성으로 옆으로 깔리며 자라기 때문에 나무 밑이나 건물 그늘진 곳의 화단용으로 적합하다. 요즘 점차 수요가 늘고 있는 옥상정원용으로 우수할 것으로 생각된다.