Ampeloviruses Associated with Grapevine Leafroll Disease: A New Group of Viruses in India

Ampeloviruses (family Closteroviridae) are filamentous monopartite, single-stranded, positive-sense RNA genome. They are transmitted by mealybugs in semi-persistent manner and vegetative propagating material remains the major route of spread. Ampeloviruses are recent addition to the plant viruses in India. Grapevine leafroll-associated virus 3 (GLRaV-3) was first ampelovirus to be recorded from India in the year 2012. Of the nine distinct species of the genus Ampelovirus, only three, Grapevine leafroll-associated virus 1 (GLRaV-1), GLRaV-3, GLRaV-4 infecting grapevine have been reported from India. The isolates of GLRaV-3 and GLRaV-4 are diverse, a few being the recombinant ones. This chapter describes the grapevine leafroll disease caused by different ampeloviruses, their geographical distribution, characterization, diversity, management strategies and also discusses about the future course of works to be taken.