Beetles on Leaf (image) University of Illinois at Urbana-Champaign Caption Plant defenses go down as carbon dioxide levels go up, the researchers found. Soybeans grown at elevated CO2 levels attract many more adult Japanese beetles than plants grown at current atmospheric carbon dioxide levels. Credit Photo courtesy of Evan Delucia. Usage Restrictions Photo may be used only with stories about the research described in the news release. Photo courtesy of Evan Delucia. 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.