A good supply of antisera to two isolates (type II and type III) of the long clostroviruses associated with grapevine leafroll (GLRV) has been produced as well as a low tittered antiserum to the type IV GLRV. Monoclonal antibodies are produced to type III of GLRV and the titer of the antibody is quite high when evaluated in ELISA tests. A clostrovirus was mechanically transmitted from leafroll (type III) infected pinot noir to Nicotiana occidentalis. Investigations revealed that this virus is not associated with grapevine leafroll disease. A high-tittered antiserum to grapevine fanleaf virus (GFLV) has been produced and quantities have been increased. A low-tittered antiserum to tomato ringspot virus (TmRV, causal agent of grapevine yellow vein disease) has been produced and efforts are underway to produce a high-tittered antiserum to this virus. The antisera conditions have been optimized for GFLV and GYW detection in ELISA tests and they are routinely being used to test the foundation stocks at FPMS. The same GFLV antiserum also being used by California Department of Food and Agriculture (CDFA), Pest Exclusion branch for testing the registered grapevine material in their registration and certification program. An antiserum to grapevine corky bark virus (GCBV) has also been produced and conditions for optimizing the reactivity of the antiserum in ELISA tests were done. Another polyclonal antiserum to GCBV has been produced. The reason for producing another antiserum for GCBV was to get a cleaner antiserum (with lower healthy background in ELISA test) by doing more rigorous purification of the virus particles. Evaluation of this antiserum is underway. Some monoclonal antibody lines were produced for GCBV but subsequently lost their ability to produce specific antibodies. Our attempt has failed to purify enough rupestris stempitting associated virus for the production of antiserum. Double stranded RNA has been consistently extracted from a grapevine infected with rupestris stempitting and we are planning to make a cDNA clone from the dsRNA and use it in a cDNA hybridization system as a diagnostic tool. A source for GLRV-type I has been identified. Amounts of virus has been purified and within next few weeks we will start immunizing a rabbit to produce specific polyclonal antibody to this virus.
/wp-content/uploads/2017/09/AFV-Header-Logo.png 0 0 AVF /wp-content/uploads/2017/09/AFV-Header-Logo.png AVF1991-11-17 07:44:152017-11-17 07:44:59Production of Antisera to Grapevine Viruses