Detection And Control Of Tobacco Viral Diseases In Mengyin

The incidences of tobacco viral diseases in Mengyin have been increased significantly and severely reduced the quality and yield of tobacco leaves in recent years.In this research,the author investigated the species and distribution pattern of tobacco viruses,effects on PGPR strain on tobacco viruses' control.The main results were as follows:1 The 714 bp coat protein gene of Potato virus X(PVX) Feixian isolate was cloned with RT-PCR and sequenced.High quality antiserum to PVX with titer of 1/1600 was prepared with coat protein expressed in E.coli.2 In the late growing stage of 2005,the incidence and index of tobacco viral diseases in Mengyin were 44%and 27,respectively.Those for the year 2006 were 68.6%and 24.9,respectively.Two year's serological detection indicated that PVY and TMV were the most prevalent viruses in Mengyin. The high incidence of PVY and frequent mixed infection of PVY and other viruses like PVX and CMV might be the major reason responsible for huge loses of tobacco production in Mengyin.3 The distribution pattern of tobacco virus diseases in Menyin was investigated.It was uniform and aggregation distribution,respectively,in the early and late tobacco-growing stage.The aggregation distribution in the late stage might be associated with spread of TMV in the field.4 Primary tests on the role of PGPR strain,Lyc2 and TC6,to control tobacco viruses were conducted both in the greenhouse and the field.Lyc2 and TC6 showed efficiencies of 67.2%and 42.6%to TMV in Nicotiana tabacum cv samsun in greenhouse,and 26.6%and 33.7%to viral diseases in N. tabacum cv Zhongyan 100 in the field.The PGPR strains can also promote the growth of tobacco and hava great potential in the future.These results will be helpful to the control of tobacco viral disease in Mengyin.