Submitted to: Plant Disease
Publication Type: Peer reviewed journal
Publication Acceptance Date: 11/4/2003
Publication Date: 1/1/2003
Citation: Meng, B., Credi, R., Petrovic, N., Tomazic, I., Gonsalves, D. 2003. Antiserum to recombinanat virus coat protein detects Rupestris stem pitting associated virus in grapevines. Plant Disease. 87:515-522. Interpretive Summary: Movement of grapevines to countries worldwide is generally governed by quarantine regulations, which require testing of imported grapevines for viral diseases. Although inoculation to grapevine indicator plants is the standard method for testing imported grapevines, faster techniques such as serology, herbaceous indicators, and nucleic acid based tests would be of practical value. Rupestris stem pitting is a widespread virus disease that manifests itself when infected material is graft-inoculated to the grapevine indicator 'St. George'. This test takes about two years to complete and thus a more rapid test is desirable. In this article, we produced antibodies to the coat protein of the causal agent Rupestris stem pitting associated virus and successfully used the antibody to serologically detect the virus in grapevines. The tests took only several days to complete and matched with those obtained on 'St. George'. These results show that serology is a promising, practical and rapid alternative that can be used to index imported grapevines for Ruepstris stem pitting associated virus.
Technical Abstract: Rupestris stem pitting (RSP) is the most widespread virus disease of grapevines. The genome of Rupestris stem pitting associated virus (RSPaV), the putative causal agent of RSP, was recently sequenced. Until recently, the only method to diagnose RSP was biological indexing on woody indicator plants, a process that takes two to three years to complete. This study reports on the production of a polyclonal antiserum to a recombinant coat protein of RSPaV. The antiserum was used effectively to detect RSPaV from various genotypes and tissues of grapevines by Western blot and indirect enzyme-linked immunosorbent assay. Virus antigens were consistently detected in the cambium of dormant canes and in actively growing leaves of grapevines. Moreover, plants of Vitis rupestris 'St. George', the standard biological indicator for RSP, tested positive for RSPaV. The serological methods developed in this study are advantageous as compared with biological indexing because they are more rapid, less expensive, as reliable, and more suitable for assays of a large number of samples.