| Causal agent: |
Phoma betae (= Pleospora betae) |
| Symptoms: |
Large, bright, round lesions develop on the leaves with concentrically dark rings consisting of numerous pycnidia. Often the dead tissue becomes brittle. |
| Economic importance: |
The pathogen mainly attacks beet seed crops, but is rarely of economic importance in industrial beet cultivation. |
| Control: |
Due to the low losses caused by this disease, it is not worthwhile controlling. The disease can be seed borne and all beet seed is treated with Thiram as a protection. |
