Detection and Analysis of Tobacco Viruses and Infection Type in Henan Province

To further clarify the main virus species and infection type in Henan Province,407 samples were collected from nine tobacco-growing areas in Henan Province in 2020.The samples were suspicious of being infected by Tobacco mosaic virus (TMV), Cucumber mosaic virus (CMV),Potato virus Y (PVY) and Tobacco etch virus (TEV) respectively.Then four pairs of specific primers were used to detect viruses that infected tobacco samples by single RT-PCR.The results showed that the infection percentage of virus diseases in Henan tobacco-planting areas was 98.28%,in which CMV (89.19%) took the top spot followed by TMV (63.88%),PVY (28.99%) and TEV (24.32%).It also suggested that infection type included single infection and co-infection.What's more,single infection rate was 23.34%,in which CMV had the highest infection percentage with 16.71%.And co-infection percentage was 74.94% which was much higher than the single infection rate.Furthermore,there were three main co-infection types,including CMV+TMV with the highest infection percentage 36.86%,followed by CMV+TMV+PVY and CMV+TEV+PVY which both had an infection percentage of 7.62%.Therefore,CMV was the dominant virus in Henan Province in 2020.And the infection types were CMV+TMV, CMV+TMV+PVY and CMV+TEV+PVY,which indicated that co-infection types occurred seriously in tobacco field.