How does UV and infra-red affect plants?

Question

Yes, It is that time again: the science fair.

I am working on how coloured lights affects plants, and sicne I already know light has infra-red and UV in it, I need to know exactly what it does to the plant.

(PLANTS USED: NASTURTIUMS)

Answer 1

Infrared (IR) light is probably more important than UV in terms of biological effects.  IR does not support photosynthesis but has effects on developmental processes like flowering.  UV can support photosynthesis but this type of light can cause damage to tissues and DNA.  So its liabilities may outweigh its benefits.  Indeed, to the extent that you observe any effect of light color on plant growth then it is most likely to be due to nonphotosynthetic effects of light on development processes rather than on photosynthesis.