While it produces several phytotoxins, the most prevalent in the disease cycle is brefeldin A. Brefeldin A is capable of inhibiting phytoalexin synthesis used in the safflower’s chemical defense against pathogens.
The pathogen produces various toxic compounds, but one of the most significant is brefeldin A. This toxin interferes with the production of phytoalexins in safflower, which are chemicals that help protect the plant from pathogens.