CIAT Colombia employs unique chamber with two independently controlled growth zones
Mar 28, 2017
The Center for Tropical Agriculture (CIAT) in Colombia uses a unique plant growth chamber design to enable experimentation with light quantity and quality for its large in vitro collection. Since researchers cannot experiment on the in vitro collection itself, they needed a way to study separate plant material so that changes in light spectrum or quantity may be contemplated for the whole collection.
CIAT’s solution was to use one plant growth chamber with two independently controlled growth areas. The growth chamber is a smaller reach in style unit with an internal capacity of 17 ft3 (480l) (Conviron, E7/2). One unique feature of CIAT’s chamber is that the top growth zone can be controlled and monitored independently from the bottom. Because the top and bottom zones function separately, the chamber can accommodate CIAT’s need to expose plants to different experimental conditions within the same chamber. CIAT’s chamber can then run consistent temperature, humidity, and airflow conditions on both the top and bottom zones while changing the light intensity (top and bottom tier) and spectrum (top tier) plants are exposed to.
To accommodate the different light intensities and spectrum the bottom half of the chamber is outfitted with T8 fluorescent and halogen incandescent lighting while the top shelf utilizes LED lighting (Heliopspectra, RX30). In order to not lose growth space within the top zone and remove heat from the growth area, engineers cut out recesses on the top of the chamber to optimally situate the LED lights.
| Parameters | Top Zone | Bottom Zone |
|---|---|---|
| Temperature | +4°C to +45°C lights OFF, +10°C to +45°C lights ON (Full fresh air) | +4°C to +45°C lights OFF, +10°C to +45°C lights ON (Full fresh air) |
| Humidity | Up to 90% RH lights OFF and 85% RH lights ON, limited by a +25°C maximum dew point (empty chamber) Additive humidity through use of spray nozzles | Up to 90% RH lights OFF and 85% RH lights ON, limited by a +25°C maximum dew point (empty chamber) Additive humidity through use of spray nozzles |
| Lighting | 400 micromoles/m²/s using two (2) RX30 Heliospectra grow lights | 400 micromoles/m²/s, Light measurement at 6" (150mm), chamber temperature of 25°C |
| Airflow | Uniform upward | Uniform upward |
The two zone solution employed by CIAT may be a suitable approach to other research programs requiring different growing environments but with limited space to do so.
