Bahder, B.W., Poojari, S., Alabi, O.J., Rayapati, N., & Walsh, D.B. 2013 Pseudococcus maritimus (Hemiptera: Pseudococcidae) and Parthenolecanium corni (Hemiptera: Coccidae) are Capable of Transmitting Grapevine Leafroll-Associated Virus 3 between Vitis x labruscana and Vitis vinifera. Environmental Entomology 42(6):1292-1298

Notes: The grape mealybug, Pseudococcus maritimus (Ehrhorn), and European fruit lecanium scale, Parthenolecanium corni (Bouche´), are the predominant species of Coccoidea in Washington State vineyards. The grape mealybug has been established as a vector of Grapevine leafroll-associated virus 3 (GLRaV-3) between wine grape (Vitis vinifera L.) cultivars, elevating its pest status. The objective of this study was to determine if GLRaV-3 could be transmitted between Vitis x labruscana L. and V. vinifera by the grape mealybug and scale insects. Three transmission experiments were conducted with regard to direction; from V. vinifera to V. x labruscana L., from V. x labruscana L. to V. x labruscana L., and from V. x labruscana L. to V. vinifera. Each experiment was replicated 15 times for each vector species. Crawlers (first-instars) of each vector species were allowed 1-wk acquisition and inoculation access periods. The identities of viral and vector species were conÞrmed by reverse transcription-polymerase chain reaction, cloning, and sequencing of species-specific DNA fragments.GLRaV-3 was successfully transmitted by both species in all experiments, although Ps. maritimus was a more efficient vector under our experimental conditions.To the best of our knowledge, this study represents the first documented evidence of interspecific transmission of GLRaV-3 between two disparate Vitis species. It also highlights the potential role of V. x labruscana L. in the epidemiology of grapevine leafroll disease as a symptomless source of GLRaV-3 inoculum.