Cloning Of TEV CP, HC-Pro And Cross Protection Between Tobacco Etch Virus And Sugarcane Mosaic Virus

The tobacco etch virus disease is one of the most severe diseases of tobacco and spreaded recently in China. The article introduces cross protection between SCMV and TEV in potyvirus for the first time, which develops a new idea of plant virus control, our results showed:1. We cloned CP and HC-Pro (DQ365889) of TEV from Shaanxi province. The nucleotide and amino acid homologies were 97.34%, 96.66%, 99.2%, 99.78% as compared with the American TEV, and 50.64%, 53.2%, 69.65%,82.2% as compared with the SCMV from Shaanxi province, respectively.2. TEV CP was inserted into pET30a, we constructed the expression vector of pET30-TEVCP. The molecular size of expression product was approximately 37 ku induced by IPTG. The product was used as antigen to immunize the rabbit and the titer of antiserum was 1:128 with double diffusion. The protein was prepared for antiserum to increase the sensitivity of detection.3. We inserted TEV CP into pPIC9K and constructed the eukaryotic expression vector pPIC9K-TEVCP to get high activity protein. The molecular size of expression product was approximately 37ku induced with 1% methanol, and reacted to the antiserum immunized with expressed proteins from the BL21 strain of pET30a. The protein was prepared for antiserum to increase the sensitivity of TEV detection.4. In the greenhouse, tobaccos were coinoculated with the mixture of 10%SCMV and 1-2%TEV in treatingâ… ; tobaccos were chanllenged with 1-2%TEV at 7 days after protecting with 10%SCMV in treatingâ…¡; tobaccos were challenged with 1-2%TEV at 0.5, 1, 3, 5, 7, 9, 11, 15, 20 days following previous inoculation with 10%SCMV in treatingâ…¢; tobaccos in CK1 were protected but not challenged, those in CK2 were challenged but not protected, and those in CK3 were neither protected nor challenged but mock-inoculated with PBS and carborundum.The ratio of cross protection between SCMV and TEV in treatingâ… ,â…¡was 61.0% and 54.4% , respectively at 21 days after the challenge inoculation. When the interval of two inoculations was 1, 3, 5, 7, 9 days, the ratio of cross protection was 66.6% in treatingâ…¢; when interval was 0.5, 11, 15, 20 days, the ratio of cross protection was 60.0%.In the fields, two rows of maizes were planted around tobaccos in treating A; we grown five rows of tobaccos every other row of maizes in treating B; two rows of tobaccos...