First Report and Molecular Characterization of Umbra-like Virus on Ficus carica Caprifig Trees in Crimea.

Fig mosaic is the most serious viral disease affecting figs. A fig germplasm collection from the Nikita Botanical Garden on the Crimean Peninsula was surveyed for viruses using high-throughput sequencing and RT-PCR with primers specific to known fig viruses. Reads related to fig umbra-like virus (FULV) were generated in samples from Ficus carica caprifig (pollinator) trees of the cultivar Belle dure. F. carica trees of other cultivars, as well as F. afghanistanica , F. palmata , and F. virgata trees, tested negative for FULV. Near-complete genomes of five Crimean fig umbra-like virus (FULV-CR) isolates shared 99.4% to 99.9% identity and were most closely related (85.2% identity) to the Hawaiian FULV isolate Oahu1 (MW480892). Based on their genome structure and a phylogenetic analysis, the FULV-CR isolates were determined to be dicot-infecting Class 2 umbra-like viruses and seem to be highly divergent forms of the same virus found recently in Hawaii, USA. This is the first report of an umbra-like virus found on figs in Crimea and outside of Hawaii, expanding information on the geographical distribution and genetic diversity of FULV. All of the Crimean FULV-positive plants were also co-infected with fig mosaic virus, fig badnavirus 1, and grapevine badna FI virus.