Powdery Mildew on Thale Cress (IMAGE) Max-Planck-Gesellschaft Caption These are thale cress (Arabidopsis thaliana>I>) plants with powdery mildew infection. The white coating on the infected leaves, which originates from the mycelium on the leaf surface, is a typical feature of mildew infection. Credit Ralph Panstruga Usage Restrictions None 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.