2005 Volume 43 Issue 2 Pages 113-119
The objectives of this study were to investigate the effect of short-term changes in the spectral environment on photosynthesis. Lettuce (Lactuca sativa) plant were grown under red-greenblue (RGB) light-emitting diodes (LEDs) for 23 d and then given 24-h exposure to red (R), redgreen (RG), or red-blue (RB) LEDs. Photosynthetic rates (Pn) were measured before the 24-h exposure, after 24-h exposure, and 24 h after returning to the original RGB lighting. Temporary changes in spectral quality affectedPn. The effects of the different light treatments onPnreversed after returning to the initial light source. This study showed thatPnwas responsive to spectral quality in the short-term and is not directly coupled to stomatal conductance.