#$%^&*AU2014202160B220170713.pdf#####- 27 ABSTRACT [Object] To provide a plant growth apparatus of multistage rack type, which can efficiently dissipate heat from an artificial lighting unit to the atmosphere, and which can prevent a rise of temperature of a nutrient solution flowing on a tray disposed just above the artificial lighting unit and a rise of temperature of rhizospheric portions of plants put on the tray, and a plant growth system including the plant growth apparatus of multistage rack type. [Solution] In plant growth apparatuses 3 to 6 of multistage rack type including artificial lighting units 13 disposed at lower surfaces of racks, each artificial lighting unit 13 includes a box 13a disposed on the lower surface side of the rack, a fluorescent lamp 13c, and a power supply unit 13g. The power supply unit 13g is disposed on a bottom plate 13e of the box 13a, and the power supply unit 13g and a top plate 13d are spaced from each other. The bottom plate 13e serves also as a reflecting plate for the fluorescent lamp 13c. [Selected Figure] Fig. 7
