First Report of Rupestris stem pitting associated virus in Argentina.

Rupestris stem pitting associated virus (RSPaV), a component of the rugose wood complex (RWC), is a worldwide graft transmissible disease of grapevines (Vitis vinifera L.). RSPaV has a single-stranded 8,726-nt RNA genome, belongs to the genus Foveavirus, and is often associated with Rupestris stem pitting (RSP) disease (2). In 1995, a grapevine sanitary selection program was implemented in Mendoza to investigate this and other grapevine viral diseases. RSP can be diagnosed when V. rupestris cv. St. George is used as a woody indicator for biological indexing. Chip-bud inoculated St. George plants developed a row of small pits and grooves on the wood cylinder below the graft or around and below the inoculated point (1,2). After three seasons in the field, 15 accessions with RSP wood markings were observed. Mature leaves and bark shavings were extracted, partially purified, and analyzed by a onestep reverse transcription polymerase chain reaction method. The expected 339-bp band was found in only six of the positively indexed samples using the specific 13/14 primer pair (2). Other viruses associated with RWC have been detected in Argentina, but to our knowledge, this is the first report of RSPaV. References: (1) A. C. Goheen. Page 53 in: Compendium of Grape Diseases, R. C. Pearson and A. C. Goheen, eds. American Phytopatological Society, St. Paul, MN, 1988. (2) B. Meng. Rupestris stem pitting: Insights on etiology and development of reverse transcription-polymerase chain reaction and immunoassays for diagnosis. Ph.D. Diss. Cornell University, Ithaca, NY, 1999.