Meten en sturen van plantbelasting in sierteeltgewassen: Onderzoeksproject in opdracht van het programma Kas als Energiebron

On behalf of ‘Kas als Energiebron’, WUR has made good definitions and plant physiological interpretation of the terms plant load, assimilate balance and plant balance for ornamental crops: Plant load is the total sink/m2 greenhouse / week and is determined by the number of harvestable organs per m2 per week, the developmental stage of these organs and the assimilate requirement of other plant parts. Assimilate balance is a certain relationship between the demand for assimilates (= sink demand) and the supply of assimilates (= source) in such a way that the plant can grow and deliver the desired product quality as needed. Plant balance is a certain balance in the production and growth of harvestable and non-harvestable plant parts, in such a way that the plant can grow and deliver the product quality the grower wants. This is broader than the assimilate balance and also relates to, among other things, control in the energy balance, water balance, hormone balance and nutrient balance. Controlling plant load, assimilate balance and plant balance has been described for Gerbera,Chrysanthemum, Rose and Freesia and a classification has been made for floricultural crops based on crop characteristics for controlling plant load. By adjusting the plant load to the expected light sum, growth can be adjusted according the amount of natural light in winter and savings van be made on heat and electricity input. Monitoring the plant balance is also an aid in the implementation of new (energy saving) measures to quickly and consciously adjust changes in crop growth to the desired plant quality.