ARS | Publication request: First report of Streptomyces stelliscabiei causing potato common scab in Michigan

Submitted to: Plant Disease
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: March 8, 2012
Publication Date: June 1, 2012
Citation: Jiang, H.H., Meng, Q.X., Hanson, L.E., Hao, J.J. 2012. First report of Streptomyces stelliscabiei causing potato common scab in Michigan. Plant Disease. 96(6):906.

Interpretive Summary: Common scab is an important potato disease. The pathogen also can affect other crops. In Michigan, the primary pathogen known to cause scab is Streptomyces scabies. Isolates were collected from diseased potato that did not fit this species. They were determined to be S. stelliscabiei, a species known to cause scab in other growing areas, but not previously found in Michigan potato. The Michigan isolates caused symptoms on potato and radish when tested for their ability to cause disease. It is important to know the species involved to make management decisions.

Technical Abstract: Streptomyces scabies has been reported as the predominant cause of potato scab in Michigan. In a 2007 survey of common scab in Michigan, however, isolates were collected from a field that did not fit the description for S. scabies. Tests using species-specific PCR primers indicated isolates were S. stelliscabiei. Identification was confirmed by sequencing the 16S rDNA, which showed 99-100% identity with S. stelliscabiei in Genbank. S. stelliscabiei isolates have been demonstrated to cause potato scab in other growing areas. Michigan isolates caused necrosis of potato tubers and produced scab lesions when inoculated onto radish. To the author’s knowledge, this is the first report of S. stelliscabiei causing potato scab in Michigan.