T. Schwend, M. Beck, D. Prucker, S. Peisl and H. Mempel
Institut für Gartenbau, University of Applied Sciences Weihenstephan-Triesdorf, Freising, Germany

SUMMARY The intensity, and consequently the energy consumption, of light emitting diodes (LEDs) can be regu-lated. Therefore, LEDs can be implemented in new, dynamic energy saving strategies. Recently it has been shown that a program, which adjusts the intensity of a LED to the current solar PAR, reduced its energy consumption by 20%. The effect of a dynamic LED lighting on ornamental crops has not been tested. In this study we compared the growth of the model plant Helianthus annuus under a dynamic versus a static, control LED lighting. The data of this study show that the dynamic LED consumed 21% less energy than a control LED. However, there was no difference in crop quality or time to anthesis. Keywords energy conservation, light intensity, light quality, photosynthetically active radiation

Significance of this study What is already known on this subject? A recent study has shown that application of a dynamic LED lighting reduced energy consumption, but also reduced vegetable yield. What are the new findings? The dynamic LED lighting reduced energy consumption without affecting the quality or yield of sunflowers. What is the expected impact on horticulture? This study provides a proof of principle that a dynamic LED lighting is applicable to floriculture.

E-mail: heike.mempel@hswt.de  

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Received: 26 February 2016 | Revised: 15 April 2016 | Accepted: 23 May 2016 | Published: 20 June 2016 | Available online: 20 June 2016