Molecular characterization of wild tomato mosaic virus and chilli veinal mottle virus mix‐infecting chilli pepper in China

The present study described molecular characterization of two potyviruses: wild tomato mosaic virus Dehong isolate (WTMV-Dh) and chilli veinal mottle virus Dehong isolate (ChiVMV-Dh) mix-infection chilli pepper and assessed their mix-infection on chilli pepper. Transcriptome next-generation sequencing technology (NGS) and RT-PCR were used to obtain the complete genome sequences of the abovementioned two viruses. The results showed that the complete sequence of WTMV-Dh is 9675 nucleotides (nt) in length and encodes a complete polyprotein of 3075 amino acids (aa). The WTMV-Dh polyprotein shares 76.1%-82.6% nt and 85.3%-89.5% aa identities with three previously reported WTMV isolates. The complete sequence of ChiVMV-Dh is 9736 nt in length and encodes a complete polyprotein with 3, 089 aa. ChiVMV-Dh polyprotein shares 80.8%-92.2% nt and 85.3%-95.6% aa identities with previously reported ChiVMV isolates. Following phylogenetic analysis based on the polyprotein sequences of potyviruses revealed that WTMV-Dh clustered with the Vietnam strain WTMV-Laichau, while ChiVMV-Dh clustered with several ChiVMV Sichuan isolates. The mix-inoculation experiment showed that the mix-infection of these two viruses has more severe symptoms than single-infection.