First Report Regarding Potato Scab Caused by Streptomyces acidiscabies in Uruguay

Potato scab disease is caused by gram-positive filamentous bacteria in the genus Streptomyces. A great variety of species cause this disease, but Streptomyces scabies is the most ancient of these pathogens and can be found in a worldwide distribution, whereas S. turgidiscabies and S. acidiscabies are newly emerged pathogens (2). During the autumn of 2010, potato (Solanum tuberosum) crops had large economic losses by common scab, corresponding to 29% of the total potato-cultivation area (according to our survey), which was unusual in Uruguay. Specifically, the disease was very aggressive and the tubers showed particularly deep scab lesions. We isolated the Streptomyces species present in these particular scab lesions of tubers collected in July 2010 from one of the three potato cultivation areas (San Jose). A total of 19 Streptomyces spp. strains were isolated and identified using classical and molecular techniques. Morphological characteristics of colonies and microscopic structure of the mycelium were ob...