The Enviratron is an automated plant growth and imaging facility that is used to assess plant performance under a variety of environmental scenarios.  The Enviratron consists of eight custom-made plant growth chambers that can support the growth of crop and model plants under up to eight different environmental conditions in a single experiment. The environmental parameters that can be adjusted are: carbon dioxide concentration, day length, light intensity, light quality, temperature, humidity, and soil water content. The most unique aspect of the growth chambers is that a robotic rover can enter them on-demand without disrupting the plant growth conditions. The rover operates autonomously and carries an array of cameras and sensors that collect data according to user-specified schedules. The robotic imaging enables cameras and sensors to be deployed at the optimal angles and distances from the plant canopy, and it also enables the use of a fluorometric probe that measures chlorophyll fluorescence, which must be oriented to the target leaf surface at a specific distance and angle. The data are uploaded from the robot to a local server and then transferred to the NSF CYVERSE Data Store for long-term storage and community access once released to the public. An experimental scheduler was developed that captures key information about the phenotyping experiments so that they can be repeated and the data are useful to other scientists over the long-term. The scheduler provides an interface between the user and the Enviratron system so that the Enviratron is programmed with the environmental settings of each growth chamber, the numbers and locations of plants in each chamber, and activities of the robot.

The interdisciplinary team met together monthly during the first four years of this project to plan, problem-solve, and evaluate progress.  One group of engineers designed and constructed the plant growth chambers, while another group of engineers developed the robotic rover.  One group of bioinformaticists and data analysts developed the software and the data collection pipeline, while another group developed the image analysis.  A group of facilities personnel designed and built the building and developed the utilities to serve the Enviratron.  A group of statisticians developed experimental designs for conducting experiments and another group of plant scientists evaluated the plant physiological parameters for different species of plants grown in the facility.  These scientists and engineers devoted part of their careers to this project and would not have had the chance to work together under other circumstances.  We have a team of people who are willing, able, and interested to work together across disciplines in the future.  For the young scientists - the undergraduates and graduate students in particular - this was an extraordinary learning experience that they would not have had if they had been working on their own or in their own independent lab groups.

Another important outcome was the close and productive interaction between the Iowa State researchers and the engineering team at Percival Scientific, which was an important learning experience for both the academic and industrial scientists and engineers.  The partnership went far beyond the usual contractual relationship of acquiring goods or materials from a company.  The engineers at Percival helped to develop the concept, design the components, and met with the team to come up with solutions to challenges in building this unique facility.

Finally, the Enviratron is performing as envisioned by supporting cutting-edge science related to environmental effects on the growth, development, and physiology of crop plants. We have demonstrated that physiological processes that occur in nature also occur in the controlled growth conditions.  One example is the research recently published in The Plant Cell concerning the effects of diurnal temperature cycles on the induction of stress in maize.  The research could not have been done without the Enviratron, because it required the use of all eight chambers in the Enviratron to simulate different daily temperature cycles and robotics to monitor the performances of plants under those conditions.  The Enviratron is one of the few facilities in the world that can grow crop plants, such as maize and soybean, under controlled conditions in many different environmental regimes that simulate past, current, and future climate scenarios. 

Last Modified: 11/27/2020
Modified by: Steven A Whitham