Symptom database
It is obvious that powdery scab can have many different types of symptoms on tubers. This can make proper identification difficult. For instance the raised form of Streptomyces can be mistaken for powdery scab or vice versa, especially when unwashed potatoes are inspected.
It was therefore suggested to establish a picture database. T h i s i dae has not been realized. But in the meantime, there was a usefull website estalished to help with symptoms recognition and cause identification: