Phytochrome-mediated detection of changes in reflected light
1Department of Biological Sciences, Columbia University, New York, New York 10027.
Plant Physiology
|January 1, 1991
Summary
Plants can detect nearby plants by sensing changes in reflected light. This phytochrome-mediated perception occurs before shading, allowing early detection of neighbors.
Area of Science:
- Plant biology
- Photomorphogenesis
- Plant physiology
Background:
- Phytochrome is a key photoreceptor regulating plant growth and development.
- Light quality and quantity influence phytochrome states and plant responses.
- Plants may perceive environmental cues through light perception.
Purpose of the Study:
- To investigate if Cucurbita pepo L. seedlings can detect changes in reflected light.
- To determine if phytochrome mediates the perception of reflected light.
- To test the hypothesis that plants can sense neighbors via reflected light before shading.
Main Methods:
- Seedlings of Cucurbita pepo L. were grown in controlled light environments (growth chambers).
- Measurements of phytochrome photoequilibria and photoconversion rates in vivo were conducted.
- Simulations approximated natural sunlight conditions, including direct and reflected light.
Main Results:
- Changes in reflected light quality and quantity significantly altered phytochrome states in seedlings.
- These alterations occurred even when reflected light constituted a small fraction of total radiation.
- The observed changes were consistent with phytochrome-mediated light perception.
Conclusions:
- Cucurbita pepo L. seedlings exhibit phytochrome-mediated responses to changes in reflected light.
- Plants may perceive the presence of nearby vegetation through altered light reflectance.
- This mechanism could enable plants to detect neighbors before physical shading occurs.
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