Onderzoek stuurlicht Freesia winter 2012-2013 : praktijkonderzoek met lage intensiteit LED belichting tijdens de donkerperiode

Low intensity red or far-red LED light (4 µmol.m-2.s-1) during the dark period was tested in a commercial greenhouse (Akerboom Freesia). During the day assimilation lighting was used. The trial showed no clear effect on production. At the first planting date, plants showed symptoms of virus, so no production counts were carried out. At the second planting date, only small differences in production were observed (max. 6% difference in production) and there was no clear correlation with the treatments. This might be a result of low intensities of red and far-red light reaching the control plots and/or the variety used in this experiment (Ambassador). The production increase varied from 5% for the variety Albatros to 22% for the variety Red Beauty in a previous experiment with red and far-red LED light on Freesia. Ambassador maybe less sensitive to low intensity LED light during the dark period than the other cultivars.