Monitor And Analysis Of Virus Disease In Floating System Of Lijiang

Virus diseases are bottlenecks of tobacco production, there are more than 30 viruses in tobacco. The symptoms show mosaic and leaf curl in tobacco. In this study, we do something about virus species, route of transmission, detected methods, prevention and control methods in tobacco.In this paper, the nursery substrates, water in seedling production, root residues in the walls of float tray was detected by TMV TAS-ELISA kit. The results showed that TMV was detected in the nursery substrates, water and root residues. So we consider the condition as primary source of infection of TMV.Since 2007, we used TAS-ELISA to detected TMV in floating system of Lijiang and to make progress. The incidence of disease of TMV showed come down every year. In 2014, the positive rate was 1.02%, compare with positive rate of 2013 was decline.Use ELISA and microscope to detected TMV, CMV, PVY and PVX in Lijiang. The results showed all of these viruses can be detected in Lijiang. The positive rates of TMV, CMV, PVY and PVX is 85%,15%,10%,11%, respectively.The 144 disease samples of tobacco were collected from west of Yunnan province and detected TMV by DOT-ELISA. The results indicated there are samples show positively with TMV antiserum, the positive rate was. Choose 1 sample every area to amplicate the cp gene of TMV and to analysis the genetic diversity. Construct the phylogenetic tree of TMV cp, the 15 TMV isolations was get together with TMV-U1. So we conclude the 15 isolations of Yunnan province are TMV-U1 isolate.