Partial genomic sequence of a new Tobamovirus from Piper

Several Piper spec. of tropical origin are of economic importance. Besides those grown for agricultural black pepper production, some are used as ornamental plants. In spring 2014, several plants of an ornamental Piper cultivar were observed showing severe chlorosis. Electron microscopical examinations revealed the presence of rod-shaped particles resembling those of tobamoviruses. Following mechanical inoculation, dsRNA of ca. 6.5 kbp could be extracted from systemically infected Nicotiana benthamiana plants exhibiting crinkling and mottling symptoms, which is within the size range of assigned Tobamovirus species. Extracted dsRNA served as a template for a random RT-PCR and cloning approach. Obtained sequences were assembled into a contiguous sequence, containing four putative open reading frames in an arrangement characteristic of members of the genus Tobamovirus. An almost complete coding region of the genome was obtained, lacking ca. 140 N-terminal amino acids of the replicase. The sequence showed the highest overall nucleotide (nt) sequence identity with 67.4% to an isolate of Odontoglossum ringspot virus. Even though the entire sequence is not yet available, this virus can be regarded as an isolate of a new Tobamovirus species based on the molecular ICTV species demarcation criteria (<90% overall nt identity). The name Piper chlorosis virus (PChV) is suggested for this isolate which is available at the DSMZ Plant Virus Collection under accession no. PV-1126.