Alexandra Weisberg (Jeff Chang lab, in collaboration with Dr. Christopher Clarke at USDA-ARS in Beltsville MD) is lead author on a new paper published in MPMI, currently viewable as a “First Look”.

The Streptomyces genus includes several species that cause common scab to tuber crops. One crop in particular, is potato. Common scab causes lesions on the surface of tubers and makes them unmarketable. The Streptomyces genus is extremely diverse, and the identities of plant pathogenic species have not been sufficiently resolved. Doing so is critically important to inform on disease management.

In this study, the authors combined use of whole genome sequencing and disease testing to uncover a new species of pathogens within the Streptomyces genus. Surprisingly, despite each sequenced member carrying all genes necessary for causing common scab, not all members produced the toxin necessary for disease and not all caused disease to potato. Hence, even within a single pathogenic species of Streptomyces, there can be diversity in aggressiveness on potatoes. Findings from this work provide a new framework for understanding the pathology of Streptomyces on potato. 

View First Look at Molecular Plant-Microbe Interactions.