Molecular characterization of a new badnavirus infecting green Sichuan pepper (Zanthoxylum schinifolium).

A new virus with a circular double-stranded DNA genome was discovered in green Sichuan pepper with vein clearing symptoms. Its complete genome of 8,014 bp contains three open reading frames (ORF) on the plus strand, which is typical of members of the genus Badnavirus in the family Caulimoviridae. Sequence comparisons revealed that the new virus has the highest nucleotide sequence identity with grapevine vein-clearing virus (GVCV). In particular, the identity of the two viruses in the ORF3 RT-RNase H region is 71.9%, which is below the species demarcation cutoff of 80% for badnaviruses. Phylogenetic analysis also placed the new virus with GVCV in a cluster. The virus was tentatively named "green Sichuan pepper vein clearing-associated virus" (GSPVCaV). The geographical distribution and genetic diversity of GSPVCaV were studied. Another isolate was found to be highly divergent.