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What happens to bean plants grown under red, blue, and green light?

If you have five lima bean plants, one grown under natural light, one under red light, one under blue light, and one under green light, how would each plant grow? And which color of light is most effective for bean plant growth: red, blue, or green light?

Plants need the full spectrum to grow well. With any limit in the spectrum they will suffer a drop in growth rate as all parts of the visible range can contribute to plant growth but if light is limited they will struggle.

Plants respond most to light in two peak ranges for photosynthesis. The first peak is in the blue range (430 to 450nm) and the second peak, is in the red range (680 to 700nm) but they respond across the spectrum even in ranges beyond the visible. In between these two peaks, in the green spectra, the absorbance rate dips.

Photosynthesis and growth regulation spans 300-800nm. Plants use light and changing light duration to keep themselves regulated to the changing seasons.
Graph of light wavelength and a plant's relative growth.

http://www.clovis.co.uk/horticultural/images/graph_lwpg.jpg

http://www.clovis.co.uk/horticultural/polythene_film_facts.htm

http://www.sankey.ws/plantlumen.html

Chlorophyll absorption spectra

http://www.botany.uwc.ac.za/ecotree/photosynthesis/spectrum.htm

http://users.rcn.com/jkimball.ma.ultranet/BiologyPages/A/ActionSpectrum.html

Wavelength and Multi-Pigment Absorption image

http://www.estrellamountain.edu/faculty/farabee/biobk/pigment.gif

http://www.uic.edu/classes/bios/bios100/lecturesf04am/lect10.htm

Vegetation or foliage plants grow best under bulbs emitting blue spectrum light. Blue is 400-475nm because chlorophyll peaks at 430 - 470nm plants use this part of the spectra.

Flowering plants require light from a red-orange emitting grow light. Red visible spectra is 580-700nm but plants also need the near infrared (~730nm) to regulate them to flower & fruit properly.

Green light is reflected so is not critical for growth.

http://www.gardeners.com/Gardening-Under-Lights/5080,default,pg.html

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