Take the 2-minute tour ×
Biology Stack Exchange is a question and answer site for biology researchers, academics, and students. It's 100% free, no registration required.

I'm trying to do some rough figuring to calculating efficiencies of various light sources for growing plants. I'm hampered, however, by the lack of a curve to multiply by the spectrum of light sources to determine the amount of photosynthetically active radiation that a typical plant will absorb and use.

I can find curves like below all over, but I can't get numerical data in the form of tables. Is there some source from where I can get such data?

PAR curve

share|improve this question
plantphysiol.org/content/early/2013/06/28/… is a starting point. He cites a paper of Mcree which may have what you're looking for (pay wall for me). Evans says that photosynthesis for 400-700nm drops off quickly as function of temperature. Red/blue encourage flowering/growth, a gardening truism which may be based on Mcree's paper. –  daniel May 19 '14 at 20:56
@daniel your link was cut off –  Nick T May 19 '14 at 21:16
This is it---plantphysiol.org/content/early/2013/06/28/… for the standard characters at the beginning ending with the three w's. –  daniel May 19 '14 at 21:32
@daniel a safer way to provide links in comments is using markdown, e.g. [Google](http://www.google.com/) = Google. The second link you pasted has a "--except" appended on the end that I had to manually remove. –  Nick T May 19 '14 at 22:37
@NickT sorry for the late comment but what do you mean here, by "numerical" –  WYSIWYG Nov 21 '14 at 18:16

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.

Browse other questions tagged or ask your own question.