Occurrence of Cucumber mosaic virus in oleander (Nerium oleander) in Hungary.
In June 2016, mosaic symptoms characteristic of viral infection were observed in a 10-year-old potted oleander (Nerium oleander) maintained in Velence (Hungary). Inoculation of test plants (Chenopodium, Cucumis and Nicotiana spp.) with extracts of diseased oleander leaves demonstrated the presence of a mechanically transmitted plant virus marked Nol. The Nol isolate caused local lesions on Chenopodium quinoa, mosaic on Cucumis sativus and local etched ring pattern followed by vein clearing and recovery on the top leaves of Nicotiana tabacum cv. Xanthi-nc. These symptoms suggested the presence of B pathotype (subgroup II strain) of Cucumber mosaic virus (CMV). Based on the results of RT-polymerase chain reaction assay and nucleotide sequence analysis, the causal agent was confirmed as CMV. This is thought to be the first record on the natural occurrence of CMV in oleander in Hungary.