Location: Horticultural Crops Research UnitTitle: A novel genetic variant of grapevine leafroll-associated virus-3 (GLRaV-3) from Idaho grapevines
|DAHAN, JENNIFER - University Of Idaho
|THOMPSON, BRANDON - University Of Idaho
|MARTIN, ROBERT - Collaborator
|KARASEV, ALEXANDER - University Of Idaho
Submitted to: American Phytopathological Society Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: 7/17/2020
Publication Date: 7/17/2020
Citation: Dahan, J., Thompson, B., Lee, J., Martin, R.R., Karasev, A.V. 2020. A novel genetic variant of grapevine leafroll-associated virus-3 (GLRaV-3) from Idaho grapevines. American Phytopathological Society Abstracts. August 10-14,2020, virtually.
Technical Abstract: Grapevine leafroll-associated virus-3 (GLRaV-3) is transmitted by mealybugs and soft scale insects, or through vegetative propagation by cuttings, and is present worldwide, wherever grapevines are grown. This virus exists as a complex of genetic variants currently classified in several phylogenetic groups, and represents a major constraint on the profitable grapevine cultivation. In the course of the GLRaV-3 testing of wine grapes in southern Idaho, plants of two grapevine cultivars were found to harbor a novel genetic variant of GLRaV-3, named ID45. The ID45 variant caused no foliar symptoms in ‘Cabernet Sauvignon’ in the fall, and was demonstrated to have poor reactivity to commercial virus-specific antibodies. The entire 18,478-nt genome sequence of the GLRaV-3-ID45 was determined using a combination of high-throughput and conventional Sanger sequencing, and demonstrated to have typical organization for the genus Ampelovirus (family Closteroviridae), with only 70 to 77% identity level to the GLRaV-3 genomes from other established phylogroups. We concluded that ID45 represented a new phylogenetic group IX of GLRaV-3. Database search using ID45 nucleotide sequence as a query suggested that this novel ID45 variant is present in at least one other grape-growing state in the U.S., in California, and in Brazil. An RT-PCR based test was developed to distinguish ID45 from the predominant, GLRaV-3 phylogroup I found in Idaho in single and mixed infections.