For decades, two different viruses were believed to be responsible for a common, untreatable disease in dahlias, a colorful, high-value flower grown worldwide. Virologists at Washington State University have now learned that the two viruses, known as dahlia mosaic virus and the dahlia common mosaic virus, are variants of the same viral species. Based on the sequencing and comparison of the viruses' genomes, the discovery was published in the journal Archives of Virology.