For classification of Cucumber mosaic virus (CMV) isolates from ornamental crops of different geographical areas, these were characterized by comparing the nucleotide sequences of RNAs 4 and the encoded coat proteins. Within the ornamental-infecting CMV viruses both subgroups were represented. CMV isolates of Alstroemeria and crocus were classified as subgroup II isolates, whereas 8 other isolates, from lily, gladiolus, amaranthus, larkspur, and lisianthus, were identified as subgroup I members. In general, nucleotide sequence comparisons correlated well with geographic distribution, with one notable exception: the analyzed nucleotide sequences of 5 lily isolates showed remarkably high homology despite different origins.
Chen, Y. K., Derks, A. F. L. M., Langeveld, S., Goldbach, R., & Prins, M. (2001). High sequence conservation among cucumber mosaic virus isolates from Lily. Archives of Virology, 146, 1631-1636. https://doi.org/10.1007/s007050170085