Nod Factors (IMAGE) Aarhus University Caption The concentrations of Nod factor are controlled by CHIT5 and this is important for establishing functional symbiosis (red nodules) versus defect symbiosis (white nodules). Credit Kasper Røjkjær Andersen, Simon Kelly and Simona Radutoiu. Usage Restrictions Image may be used only to illustrate the research described in the accompanying release. 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.