DESIGN ISSUES FOR MICROPROPAGATION LIGHTING SYSTEMS

Issues related to design of micropropagation lighting systems are inve stigated. Average photosynthetic photon pur (PPF) and mean relative de viation (MRD) are calculated using a previously developed model. A com parison of aisle versus aisle-free benching shows that the aisle-free configuration can deliver 60% higher PPF with the same energy input an d without increasing the MRD. When compared to the presence of only on e vessel, the presence of a full complement of micropropagation vessel s on a shelf is shown to reduce PPF at the vessel lid level by 5.1% an d at the plant level by 25.0%. Vessels were also found to attenuate ra diation preferentially in the 300 to 400 will range. Measurements of s pectral power distribution along the lengths of fluorescent lamps show radiation output increases above 700 nm near the ends of the lamps. T he implication that one can model and design for PPI; uniformity, and spectral quality is discussed.