Onderzoek bolblad chrysant: Resultaten praktijkonderzoek op bedrijven in De Lier en Hoek van Holland
Maaswinkel, R.H.M. ; Ieperen, W. van; Kersten, M. - \ 2011
Bleiswijk : Wageningen UR Glastuinbouw (Rapporten GTB 1079) - 32
chrysanthemum - bladeren - afwijkingen, planten - symptomen - daglicht - kunstmatige verlichting - verrood licht - aanvullend licht - schijnbaar positieve resultaten - glastuinbouw - nederland - leaves - plant disorders - symptoms - daylight - artificial lighting - far red light - supplementary light - false positive results - greenhouse horticulture - netherlands
During the growing season 2010-2011, on two nurseries, research was done on bulbous leaf by chrysanthemum. The amount of daylight is limited during the winter. It is common that the chrysanthemum-plants are lighted by SON-T lamps. The spectrum of these lamps (550 – 620 nanometres) is not corresponding to the daylight. Especially the far-red part of the spectrum is during the winter scarcely present. It supposed that caused by the shortage of far-red light the conversion of starch does not expired optimum at night for varieties which are sensitive for bulbous leaf. The natural shortage of far-red light in the spectrum can be supplemented by lightning with bulbs. On both nurseries standard cultivation is compared with cultivation in which, after a dark period of one hour light is given with bulbs during one hour. On both nurseries there were limited problems with bulbous leaf. Only one time (with the variety Anastasia Pink Star) it was possible to prevent bulbous leaf with given light by bulbs. Further on it appears that delaying of the bud formation was occurred by lighting with bulbs during the dark period.