Yellowish-white twisted inner petioles on celery plant due to infection by aster yellows phytoplasma.

Celery plant with twisted, yellowish-white inner petioles. Credit: Blair Janson, The Ohio State University, Bugwood.org<br />Licensed under a <a href="https://creativecommons.org/licenses/by-nc/3.0/us/">Creative Commons Attribution-Noncommercial 3.0 License</a>
Credit: Blair Janson, The Ohio State University, Bugwood.org
Licensed under a Creative Commons Attribution-Noncommercial 3.0 License