Our phytotron and growth chambers are equipped with different lighting systems
Discharge lamps
The FST and Bridoux sites are mainly equipped with metal halide lamps
DEL Systems
Since its renovation in 2018, the ENSAIA site has been equipped with DEL lighting systems: spotlights, rails and tubes. The lighting systems have been tested in close collaboration with the manufacturers “Froids et mesures” and “ColasseSA”. We have analyzed the light spectrum, tested the plant growth and then adapted the lights in order to obtain a unique and optimal quality for our crops.
Cartography and study of dimmability
We have made a fine mapping of the illumination of the cultivation tables and a study of the dimmability of the DEL system.
A homogeneity of more than 70% of the cultivation surface is guaranteed.
From 0% to 100% dimmability, the light intensity increases linearly, up to 1000 µmole.m².s-1 at 40 cm of the crops.
The analysis of variance shows that for the same type of light source, the illumination of the cultivation tables is identical in all phytotrons
Study of light spectra
The spectrum of our lighting systems was analyzed using a calibrated spectroradiometer and compared to the solar spectrum.
With the help of INRAE colleagues from Lusignan research institute, we analyzed the spectra and some wavelength intensity ratios in order to optimize the systems
In parallel and at each step, we grew tomatoes and studied the morphology of the plants.
With the addition of dark red DELs, the spectrum of our DELs is now close to the solar spectrum and is suitable for the harmonious growth of our plants.
Acknowledgements
The hub would like to thank the companies “Froids et Mesures” and “ColasseSA” for their support throughout the study.
We would also like to thank Vincent Dutreuil, from LIEC-Metz Research laboratory for his availability and the regular loan of the spectroradiometer.
Many thanks also to Didier Combes, Ela Frak, Cédric Perrot and Eric Roy, from the Ecophysiology Research team of the Prairies and Forage Plants Research Unit of Lusignan Research Institute.
