NORTHEAST: Two men with flashlights stand on top of 10 million pounds of chip potatoes in Exeter, ME evaluating tubers and looking for silver scurf, a potato disease caused by the fungus Helminthosporium solani. This fungus causes blemishes and lesions on the skin of the tuber, reducing tuber quality and marketable yield.
Managing silver scurf is challenging because it attacks potatoes at multiple points in the production cycle. The disease can be first introduced on the farm from infected seed. From there it can survive and overwinter in the soil, and even survives and spread into storage.
The maximum spread and infection to new potatoes takes place during the harvest handling and within the first three weeks of storage. This fungus can penetrate through natural openings of the potato skin, which starts the infection process. Symptoms from these new infections do not appear on the tubers for four to five months, which explains why the two men in this picture are on top of a potato pile in March.
To help manage this disease, use a complete crop protection program that:
- Starts with a seed treatment like CruiserMaxx® Potato Extreme insecticide/fungicide
- Follows up with an application of a fungicide like Quadris® in furrow during planting
- Treats your potatoes with a fungicide like Stadium™ as they go into storage
All photos are the property of Syngenta unless otherwise noted.
Reporting from Exeter, ME