A sunlight phytotron unit as a practical research tool

Since 1953 a Phytotron Committee at Davis has been concerned with various means of controlling the environment of plants. A glass block-roofed phytotron unit which combined the best features of the greenhouse (sunlight) and the conventional growth chamber (insulation) was built and tested as a possible research tool. The present study reports details of the phytotron unit’s construction, operation, and maintenance; energy exchanges and operating costs; efficiency of the glass blocks as a light-transmitting medium; and preliminary experiments with plants. Incandescent lighting was investigated. Other devices, including reflectors and rotation of a room to face the sun, were studied. Some of the detailed information gathered during the course of this study has been omitted from this publication. The information is available, however, on microfilm for anyone having need for further details. Directions for obtaining a microfilm of this supplementary material will be found on the inside back cover.