Fig. 4
Phylogenetic tree based on the complete nucleotide sequences of genomic segment S of previously reported TSWV isolates and ten segments sequenced herein from tobacco plant (denoted by symbolâ–²). The tree was constructed using the Maximum likelihood (ML) method using the MEGAX program. Bootstrap analysis was set at 1000 replicates.All the inoculated tobacco plants showed symptoms ten days post-inoculation (dpi). The plants inoculated with inoculum sources from Changsha showed severe symptoms compared to the ones inoculated with inoculum sources from Kunming. TSWV infection was re-confirmed through RT-PCR in all the inoculated plants. The positively detected plants were maintained as the virus source in the greenhouse. Tomato plants were then inoculated using the inoculum source multiplied in tobacco plants in the greenhouse to preserve the TSWV source in the primary host plant for long-term usage. As the tobacco plants died after a few days of showing TSWV symptoms (personal observation). While all the inoculated tomato plants showed TSWV symptoms. All the tested samples showed amplicons of the expected size in 1% agarose gel