Powdery scab is a disease cause by Spongospora subterranean f. sp. Subterranean that produces small lesions on the surface of tubers. As a consequence, it reduces the marketability of the potatoes due to undesirable cosmetic features, similar to pimples, on the tuber surface (Figure 1). These lesions can be easily removed by hand, but industrial potato peeling machines have far more difficulty removing them. This can lead to large financial losses for the seed producers because the potatoes they send to the factories often have more lesions than the machines are capable of removing. Moreover, powdery scab infected seed tubers can lead to reduced weight and yield of potatoes and render the plant more susceptible for other pathogens. Awareness of this disease has increased over the last 30 years in many countries and now known to be found worldwide where potatoes are cultivated.
At A&L Biologicals, we are developing specific techniques to reduce Spongospora subterranean f. sp. Subterranean populations on potato tubers using biological control products. We have developed a rapid diagnostic test to accurately detect and quantify the presence of Spongospora subterranean F. sp. DNA on infected tubers. This this test can be used to verify the effectiveness of the treatments and determine if they are reducing disease incidence.