First Report of Cucumber mosaic virus Infecting Chinese Mallow in China

The virus in naturally infected, stunted Chinese mallow plants and mosaic leaves was identified as Cucumber mosaic virus (CMV). Six symptomatic plants and one symptomless plant were collected in Chongqing, China. DAS-ELISA suggested CMV was likely associated with the diseased Chinese mallow. Double-stranded RNA was extracted from the samples, analysed by RT-PCR, and the coding sequences of their coat proteins (CPs) were sequenced. The results further confirmed CMV was the pathogen causing Chinese mallow stunted, mosaic disease. The isolate was named CMV-DXC. The full sequence of CMV-DXC CP was determined, and it had the highest nucleotide identity (99.4%) of those of CMV-lily, CMV-WSJ and CMV-Hnt, respectively. Phylogenetic analysis shows that CMV-DXC belongs to CMV subgroup II. To our knowledge, this is the first report of CMV infecting Chinese mallow in China.