Control measures

Currently, few, if any, cultivars have resistance to this disease. However, thin-skinned cultivars appear to be more susceptible than thicker-skinned. Consequently, the following measures are recommended for limiting black dot disease:

• use long rotations and leave at least 4 years between two potato crops;
• plant healthy seed tubers;
• seed or soil treatment can limit the disease if they are well applied and approved;
• avoid growth stress, ensure adequate water supply, with adapted fertilisation and appropriate manure and irrigation;
• limit the inoculum by destroying crop waste and infected haulms and by efficient weed control, especially for Solanum nigrum, Physalis peruviana and Datura stramonium;
• harvest no later than 3-4 weeks after haulm destruction;
• take basic precautions during storage: ensure thorough drying at harvesting and after washing; avoid condensation on tubers, especially after storage;
• maintain low storage temperature, below 5°C, as early as possible as the development of the fungus is significantly slowed down below this temperature.