Plant Resources
- 제7권1호
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- Pages.77-86
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- 2004
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- 1226-8771(pISSN)
Competition Responses of Populus alba Clone ‘Bolleana’ to red:far-red light
- Bae, Han-hong (USDA-ARS, Plant Sciences Institute, Beltsville Agricultural Research Center) ;
- Kang, Ho-duck (Department of Forest Resources, Dongguk University) ;
- Richard B. Hall (Department of Natural Resource Ecology & Management and Interdepartmental Genetics)
- 발행 : 2004.04.01
초록
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.