Morpho-Physiological Responses of L. to the LED-Sourced CoeLux System.

The CoeLux lighting system reproduces the true effect of natural sunlight entering through an opening in the ceiling, with a realistic sun perceived at an infinite distance surrounded by a clear blue sky. It has already been demonstrated that this new lighting system generates long-term positive effects on human beings; however, there are no investigations so far concerning the plant responses to CoeLux lighting. To fill this gap, the model plant L. was grown at four different distances from the light source, corresponding to four different light intensities (120, 70, 30, 20 μmol m s). High-pressure sodium lamps were used as control light. Plant phenology and morpho-physiological traits were monitored to assess for the first time the ability of plants to grow and develop under the light spectrum and intensity of the CoeLux system. Plants grown at the lower light intensities showed a delayed life cycle and were significantly smaller than plants grown with more light. Furthermore, plants grown under the CoeLux light type showed an additional deficit when compared to control plants. Overall, our results show that both the light spectrum and intensity of the CoeLux system had a strong impact on growth performance.