• Rapid Communication in Photoscience
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• 제3권3호
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• pp.53-55
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• 2014

The shade avoidance syndrome is a morphological and physiological response when plants are exposed to shade. Recent work in Arabidopsis had begun to define the molecular components of the shade avoidance syndrome in dicotyledonous model plant. However, little is known about the shade avoidance response networks in agriculturally important monocotyledon crops such as rice. Here, we found that the degree of bending at the lamina joint is inversely proportional to the R:FR ratio. To elucidate which phytochrome is involved in this response, we did lamina joint inclination assay with the rice phytochrome-deficient mutants (osphyA, osphyB, and osphyC) and the wild type plants. Whereas the osphyA and osphyC knockout mutants bent at the lamina joint in the far-red rich condition as the wild type plants, the osphyB knockout mutants no longer bent at the lamina joint in the far-red rich condition. These results suggest that PHYB acts as a sole photoreceptor in the lamina joint inclination response in rice.

• Plant Resources
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• 제7권1호
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• pp.77-86
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• 2004

The reduced ratio of red:far-red (R:FR) light acts as a measure of the proximity of competitors and plants can detect the potentially competing neighbor plants by perceiving reflected R:FR signals and initiate the response of “shade avoidance” before actual shading occurs. The phytochrome system is responsible for monitoring the changes in the R:FR and initiating the shade avoidance response. The response to low R:FR ratio was studied in a white aspen Populus alba clone ‘Bolleana’ using two filter systems: a clear plastic filter system that allows a R:FR ratio less than 1.0 to pass from adjacent border plant reflection; and a special commercial plastic that blocks FR light and creates a R:FR ratio above 3.0. The reduced R:FR signals enhanced the stem elongation in response to competition at the expense of relative stem diameter growth. Trees grown inside clear chambers were 27 ％ taller than trees grown inside the FR-blocking filter chambers. Stem taper of clear chamber trees was 16％ less than the FR-blocking filter trees. Low R:FR also induced 22％ more stem dry weight and 13％ greater petiole length per leaf compared to the FR-blocking filter trees. There were no statistically significant differences in leaf area, leaf number increment, and total dry weight between the two light filter treatments.

• Journal of Photoscience
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• 제10권1호
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• pp.157-164
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• 2003

Light exerts two primary roles in plant growth and development. Plants acquire all biochemical energy required for growth and propagation solely from light energy via photosynthesis. In addition, light serves as a medium through which plants recognize environmental fluctuations, such as photoperiod and presence of neighboring animals and plants. Plants therefore constantly monitor the direction, intensity, duration, and wavelength of environmental light and integrate these light signals into the intrinsic regulatory programs to achieve an optimized growth in a given light condition. Although light regulates all aspects of plant growth and developmental aspects, the molecular mechanisms and signaling cascades involved have not been well established until recently. However, recent advances in genetic tools and plant transformation techniques greatly facilitated the elucidation of molecular events in plant photomorphogenesis. This mini-review summarizes the gist of recent findings in deetiolation and suppression of shade avoidance response as classic examples of the phytochrome-mediated photomorphogenesis.

• 한국식물생명공학회:학술대회논문집
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• 한국식물생명공학회 2004년도 생명공학 실용화를 위한 비젼
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• pp.115-115
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• 2004

• 대한건축학회연합논문집
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• 제21권4호
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• pp.139-146
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• 2019

The purpose of this study is to propose the building design guideline considering photovoltaic panel installation through the analysis of relevant guidelines from home and abroad in terms of building design and solar panel installation. Conclusions can be summarized as followings; Considerations in building design : selection of the site with high solar accessibility, avoidance of the shade from the adjacent building & trees, south facing orientation of solar panel in building design, removal of shade on the solar panel from the part of building itself, load consideration of solar panel & fixing materials, safe passage securement for solar system maintenance, and planning of piping and mechanical room for solar system. Considerations in solar panel installation : harmonizing of solar panel with surrounding environment, unity of solar panel orientation & slope, regular maintenance of solar system, (in case of flat roof installation) solar panel installation afloat over the roof, installation area within the roof floor, and lower than parapet height, (in case of sloped roof installation) solar panel installation parallel with the roof slope, ventilation space securement below the panel, installation area within the roof surface, and similar material installation in empty space.

• 한국식물생명공학회:학술대회논문집
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• 한국식물생명공학회 2004년도 춘계학술대회
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• pp.61-61
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• 2004

• 한국산림과학회지
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• 제94권4호통권161호
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• pp.236-242
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• 2005

다양한 광조건에서 식물의 생장조절에 관여하는 광수용체인 phytochrome B(PhyB) 유전자를 교잡종 포플러 수항1호에서 분리하였다. 염기서열분석 결과, PhyB cDNA는 길이가 3,456bp 이었으며 1,156개의 아미노산으로 구성된 단백질을 암호화하고 있는 것으로 나타났다. PhyB 단백질은 아미노산 수준에서 Populus balsamfera PhyB1과 98%의 높은 상동성을 나타내었다. Northern blot 분석 결과, PhyB 유전자는 광조건에서는 높은 수준으로 발현되지만, 암조건에서는 발현되지 않는 것으로 나타났다. 본 연구의 결과들을 종합하여 볼 때 PhyB는 빛에 의하여 발현이 유도되며 광수용체 역할을 하는 것으로 여겨진다.

• 한국조경학회지
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• 제27권2호
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• pp.19-28
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• 1999

This study quantified shading, evapotranspiration and windspeed-reduction effects of trees on use and cost of heating and cooling energy in two residential neighborhoods of Chuncheon different in tree cover. Annual savings per residence of heating energy were approximately 1,210 MJ(1%) and those of cooling energy, 130 kWh(10%) in study district 1 having tree cover of about 10% . For district 2 with tree cover of about 20%, annual heating and cooling savings were 2,130 MJ(2%) and 180 kWh(19%) per residence, respectively. Trees annually saved energy costs by approximately ￦31,000 ($26, $1=￦1,200) per residence in district 1 and by ￦49,000($41) in district 2. One tree taller than 3 m resulted in annual energy savings of ￦8,000($7) in the study districts. Energy savings by trees in district 2, which had higher tree cover by 10% difference than district 1, were about 2 times greater than those in district 1. This implies that more tree plantings could enhance energy saving effects. Of the total costs saved, 58% was attributed to windspeed reduction and 47%, evapotranspiration. However, shading increased energy costs by 5% due to tree plantings at the wrong locations. Full tree plantings on the west and north of buildings and avoidance of shade-tree plantings of use of solar-friendly trees on the south are recommended to increase building energy savings efficiently.

• 한국광과학회:학술대회논문집
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• 한국광과학회 2003년도 학술대회지
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• pp.97-103
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• 2003

Phytochrome controls diverse aspects of plant development in response to the ambient light conditions. HFRl, a basic helix-loop-helix protein, is required for a subset of phytochrome A (phy A)-mediated photo-responses in Arabidopsis. Here, we show that overexpression of HFR1-N105, but not the one of the full-length HFR1, confers exaggerated photo-responses. The transgenic plants overexpressing HFR1- N105 exhibited light-independence in a subset of photo-responses, including germination, de-etiolation, gravitropic hypocotyl growth, and blocking of greening. Overexpression of HFR1-N105 also caused constitutive light-responses in the expression of some light-regulated genes. In addition, the HFR1-N105 overexpressor showed hypersensitive responses under R and FR light, dependently on phyB and phyA, respectively. End-of-day far-red light response and petiole elongation were suppressed in the HFR1-N105 overexpressor plants. Together these results imply that overexpression of HFR1-N105 activated a branch of light signaling, supporting the hypothesis that transcriptional regulation in the nucleus would be the primary mechanism of light signaling in Arabidopsis. We discuss the biotechnological potential of the mutant bHLH protein, HFR1-N105 in regard to suppressed shade avoidance syndrome.

• 한국조경학회지
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• 제26권3호
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• pp.104-117
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• 1998

Rising concern about climate change has evoked interest in the potential for urban vegetation to help reduce the level of atmospheric CO\sub 2\, a major heat-trapping gas. This study quantified the functio of home energy savings and carbon emission reduction by shading, evapotranspiration and windspeed reduction of urban vegetatioin in Chuncheon. Tree and shrub cover averaged approximately 13% in residential land. The effects of shading, evapotranspiration and windspeed reduction annually saved heating energy by 2.2% and cooling energy by 8.8%. The heating and cooling energy savings reduced carbon emissions by 3.0% annually. These avoided emissions equaled the amount of carbon emitted annually from fossil fuel consumption by a population of about 1,230. Carbon emission reduction per residential building was 55kg for detached buildings and 872 kg for multifamily buildings. Urban vegetation annually decreased heating and cooling energy cost by ￦1.1 billions, which were equivalent to annual savings of ￦10,000 savings and carbon emission reduction due to tree plantings in the wrong locations, while windspeed reduction had a great effect. Plantings fo large trees close to the west and east wall of buildings, full tree plantings on the north, and avoidance of shade-tree plantings or selection of solar-friendlytrees on the south were recommended to improve the function of building energy savings and carbon emission reduction by urban vegetation.