• 한국환경복원기술학회지
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• 제16권2호
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• pp.105-114
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• 2013

This study was carried out to find growth increasing methods of Rhododendron mucronulatum in Mt. Biseul. 4 treatments(heavy pruning, light pruning, non-pruning+fertilization, non-pruning(control)) were used in the study area with different pruning methods. Growth characteristics of new shoot, number of creation of flower buds and leaf buds in new shoot were analysed. Significant differences were observed among the treatments and stem diameter degree. Diameter, length of new shoots and the number of flower buds, leaf buds per new shoots increased in the pruning treatments. But heavy pruning showed more effective growth increasing way than light pruning. Non-pruning and fertilization treatments were not effective to increase growth of Rhododendron mucronulatum. And pruning at the end of May was the most effective way for growth of new shoot.

• Journal of Life Science
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• 제9권1호
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• pp.50-53
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• 1999

Effects of growth regulators and medium components were tested for shoot multiplication and callus growth from shoot explants of black locust. During shoot multiplication, callus growth at the cut end of shoot explants proceeded shoot development. The basal callus growth seemed to be a function of both mineral components and cytokinin supplemented in the medium. Maximum callus growth was induced by 0.5${\mu}$M BAP and the callus growth decreased as the level of BAP increased. Positive correlations were found between basal callus growth, and shoot multiplication and growth. Shoot multiplication was greatest on BSM medium (black locust shoot culture medium) supplemented with 1 $\mu$M BAP. With medium containing high nitrogen content, both shoot multiplication and growth were significantly enhanced. A new BRM medium was the most effective for rooting of black locust among three rooting media tested.

• Journal of Ginseng Research
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• 제6권1호
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• pp.11-16
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• 1982

New shoot growth of Panax ginseng root was investigated comparing with burley and soybean from l0$^{\circ}C$ to 30$^{\circ}C$ under dark. Shoot growth ceased by 12days at 30$^{\circ}C$ and optimum temperature appeared to be 15$^{\circ}C$/20$^{\circ}C$ (15hrs/9 hrs) , and 15$^{\circ}C$/15$^{\circ}C$ for ginseng. Shoot growth seems to be Poor below l0$^{\circ}C$. Temperature for maximum growth 20$^{\circ}C$/20$^{\circ}C$ for barley and 20$^{\circ}C$ /25$^{\circ}C$ for soybean. Barley did not germinate above 25$^{\circ}C$/25$^{\circ}C$, but grow better than soybean below 15$^{\circ}C$/25$^{\circ}C$. Fresh weight of 2 weeks suggesting cessation of water uptake at higher temporal use. Ginseng showed greater root ply s shoot of ginseng was linearly increased at 15$^{\circ}C$ but did not increased at 25$^{\circ}C$ after occurence of die-back of new shoot or root rot above 25$^{\circ}C$.

• 한국작물학회지
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• 제43권4호
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• pp.234-238
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• 1998

To select new germplasm for salinity tolerance from new plant type (NPT) breeding lines, the sixty F$_4$ lines selected from the crosses between Korean cultivars and IRRI's NPT lines were evaluated for salinity tolerance at the seedling stage with salinized culture solution (EC=12 dS/m) in the controlled conditions. Two NTP lines derived from a cross between 'Ilmibyeo' and 'IR66152-AC5-1', 'HR15258-7-1' and 'HR15258-27-1', were found to have good tolerance. The salinity tolerance of the lines was compared to their parents and the sensitive ('IR29') and tolerant ('Pokkali') checks in three salinity levels, no salinity (control) and an EC of 12 and 16 dS/m. Visual salinity score, shoot Na+ and Na-K ratio in two NPT lines was significantly low compared with the parents and IR29. Indicating that salinity tolerance of the lines might be derived from a transgressive segregation. The relative water content of the lines was higher than Pokkali, and the dry weight of shoot and root was proportionally decreased to salinity score and salinizing concentration. The visual salinity scores were significantly correlated with shoot Na concentration, Na-K ratio, relative water content, and reduction of dry weight (P<0.01). Their tolerance was attributed to root and shoot characteristics that led to high shoot water content, thus diluting the toxic effect of salts.

• Journal of Ecology and Environment
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• 제29권2호
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• pp.105-111
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• 2006

A natural, tidal-flat clone of Zoysia sinica was studied to compare ramet growth properties in central area with in peripheral area. In new stolon and rhizome, internode length, weight, shoot height and weight, and spike production were monitored on July 25, 2004. The weight/height rate of shoot between stolon and rhizome, the shoot/stolon (or rhizome) rate in weight between central and peripheral area were not different. However, other properties differed in stolon from rhizome or between central and peripheral area significantly differed: 1. The rhizome in central area had a larger node number, shorter internode length, higher shoot height, larger shoot biomass, and higher rate of non-shoot nodes than that in peripheral area. 2. The stolon in central area had a smaller node number, shorter internode length, and smaller biomass than that in peripheral area. 3. In the same area, the rhizome had a larger node number (except for central area), shorter internode, higher shoot height, larger shoot biomass, higher rate of non-shoot node, and higher rate of node having over two shoots than the stolon. No relationship could be found between shoot size and spike production in shoot on vertical rhizome (lower node of old shoot).

• ALGAE
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• 제25권1호
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• pp.27-35
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• 2010

Marked declines in seagrass meadows are increasingly being reported from coasts around Korea and many regions of the world. The transplantation of seagrasses has been attempted to mitigate and control their degradation from a range of anthropogenic factors. In this study, Zostera marina shoots, which were collected from a donor bed in Koje Bay, were transplanted in Jindong Bay in December 2004. In 2008, a comparative investigation of shoot morphology, growth, and reproduction strategy of Z. marina was carried out between the donor and transplant sites to assess their adaptation success. Shoot height, individual shoot weight, and leaf productivity at the transplant site were significantly greater than those at the donor site. However, below-/aboveground tissue ratio was significantly lower at the transplant site compared to the donor site. Z. marina survival was maintained through vegetative reproduction, while peak season for lateral shoot recruitment was late winter for both donor and transplant site populations. However, vegetative reproduction mainly occurred during late winter and spring at the transplant site, whereas lateral shoots were evident across all seasons except late spring in the donor site. More pronounced seasonal variations were found at the transplant site compared to the donor site. These results indicate that Z. marina populations at the two sites possess distinct phenotypic variations induced by different environmental conditions, and Z. marina transplants have adapted well to the new transplant environment.

• 원예과학기술지
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• 제32권1호
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• pp.1-9
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• 2014

This study investigated the effects of temperature on the shoot growth and flowering of potted kumquat [Fortunella margarita ( Lour.) Swingle] trees grown in subtropical conditions of I-Lan County in Taiwan. Temperature treatments included T 25-32, T 17-25, T 22, and T 18. The T 25-32 treatment trees were to the day/night temperatures of $25/18^{\circ}C$ for 2 weeks, followed by 28 weeks at $32/25^{\circ}C$. T 17-25 was exposed for 4 weeks to $17/10^{\circ}C$ followed by 26 weeks at $25/18^{\circ}C$. T 22 and T 18 were exposed at $22/18^{\circ}C$ and $18/13^{\circ}C$, respectively, for the entire duration of the experiment. Control trees were placed in a plastic greenhouse under conditions similar to the natural environment. The kumquat trees exposed to high-temperature environment of $32/25^{\circ}C$ showed more frequent and speedy sprouting of new buds, but induced the earlier termination of shoot elongation growth, resulting in decreased vegetative growth. The temperature treatments lower than $22^{\circ}C$ suppressed the new shoot production but increased the shoot growth period, resulting in increased shoot length and diameter. Temperatures higher than $25/18^{\circ}C$ readily induced flowering, with flowering being advanced under the higher temperature conditions such as $32/25^{\circ}C$. However, flowering was substantially inhibited under temperature conditions lower than $22/18^{\circ}C$, indicating the negative role of relatively lower temperatures on flowering of kumquat trees.

• 한국작물학회지
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• 제27권3호
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• pp.193-197
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• 1982

수도의 동일요소에 형성된 각 관근의 신장량은 다음과 같은 관계에 있음을 알았다. 1. 분벽아를 제거하여 각 관근만을 sink로 하였을 경우에는 중륵의 가까운 곳에 형성된 관근이 분벽아쪽에 형성된 관근보다 신장량이 좋았다. 2. 분벽아가 관근과 같이 sink로서 존재할 경우, 전출엽요소에서 출근한 관근이 가장 길었으며 또 분벽경 부근에 형성된 관근이 그 다음이었고 중륵 쪽에 형성된 관근이 가장 짧았다.

• Journal of Power Electronics
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• 제15권2호
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• pp.299-308
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• 2015

This study proposes four novel pulse width modulation (PWM) shoot-through control methods for impedance source (IS) galvanically isolated DC-DC converters. These methods are derived from a PWM control method with shifted shoot-through introduced by the authors in 2012. In contrast to the baseline solution, where the shoot-through states are generated by the simultaneous conduction of all transistors in the inverter bridge, our new approach is based on the shoot-through generation by one inverter leg. The idea is to increase the number of soft-switched transients and, therefore, decrease the dynamic losses of the front-end inverter. All the proposed approaches are experimentally verified through an insulated-gate bipolar transistor-based IS DC-DC converter. Conclusions are drawn in accordance with the results of the switching loss analysis.

• Molecules and Cells
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• 제27권6호
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• pp.615-620
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• 2009

The plant shoot meristem maintains a group of stem cells that remain active throughout the plant life. They continuously generate new cells that are then recruited for organ initiation in the peripheral zone. Stem cell proliferation and daughter cell differentiation has to be integrated with overall growth and development of the diverse functional domains within the shoot apex. Several studies have revealed extensive communication between these domains. The signaling mechanisms employed comprise diffusible peptides, directional transport of plant hormones, but also complex interactions between transcription factors, that together establish a panoply of regulatory inputs that fine-tune stem cell behavior in the shoot meristem.