Chilling chamber (IMAGE) American Society of Agronomy Caption A chilling chamber at the North Carolina State University Phytotron used to study cold tolerance of stevia plants. Credit Todd Wehner Usage Restrictions For use with this story only. License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.