Molecular Identification and Pathogenicity of a Chilli Veinal Mottle Virus Isolate from Sichuan, China

Chilli veinal mottle virus (ChiVMV) is an important potyvirus that poses a serious threat to crop production. In this study, small RNA sequencing and molecular cloning were used to obtain the complete genome sequence of a ChiVMV isolate identified in pepper plants in Sichuan (SC1 isolate). Molecular evolutionary and phylogenetic analysis of SC1 and 35 ChiVMV isolates revealed four clades of ChiVMV isolates. Recombination analysis found 23 recombinant events and 28 recombinants, with the SC1 isolate arising from the recombination of the PK isolate from Pakistan and the YNpe isolate from Yunnan, China. A full-length infectious cDNA clone of ChiVMV was constructed and demonstrated to be infectious in both Nicotiana benthamiana and pepper plants. Moreover, a Myc-tag was inserted after NIb, and the derived infectious clone of ChiVMV remained infectious, and NIb-Myc was readily expressed in infected host plants. These reverse genetic tools will promote the study of the function of ChiVMV-encoded proteins, especially the NIb protein, and facilitate basic and translational studies of ChiVMV.