Grapevine leafroll disease is caused by grapevine leafroll associated viruses (GLRaVs). Several GLRaVs have been shown to be transmitted from vine to vine by mealybugs. Within this virus complex, GLRaV-3 is the most predominant species in the world. The invasion of the vine mealybug (Planococcus ficus) in California may result in increased disease incidence of established GLRaV-3 throughout the state. We studied characteristics of GLRaV-3 transmission [effect of acquisition and inoculation access period (AAP and IAP, respectively), latent period, virus retention, and persistence of infectivity] by the vine mealybug. Our results indicate that the vine mealybug transmits GLRaV-3 in a semi-persistent manner. First instar mealybugs were more efficient vectors than adult mealybugs. Virus transmission occurred with a 1-hour AAP and peaked with a 24-hour AAP. Vine mealybugs inoculated GLRaV-3 with a 1-hour IAP, and transmission efficiency increased with longer plant access period up to 24 hours, after which transmission rate remained constant. In addition, vine mealybugs transmitted GLRaV-3 with a short latent period. After an AAP of 48 hours, vine mealybugs lost GLRaV-3 and infectivity four days post-acquisition feeding. In summary, we systematically analyzed the transmission parameters of GLRaV-3 by the vine mealybug. This information will be valuable for the development of leafroll disease management practices.
/wp-content/uploads/2017/09/AFV-Header-Logo.png 0 0 AVF /wp-content/uploads/2017/09/AFV-Header-Logo.png AVF2007-10-16 12:18:362017-10-16 12:19:47Mealybug transmission of grapevine-leafroll associated viruses