A putative new ampelovirus associated with grapevine leafroll disease

Area of Science:

• Plant Virology
• Molecular Biology
• Grapevine Diseases

Background:

• Grapevine leafroll disease is a significant threat to viticulture worldwide.
• Ampeloviruses, particularly Grapevine Leafroll-Associated Viruses (GLRaVs), are major causal agents.
• Continuous monitoring and characterization of new viral strains are crucial for disease management.

Purpose of the Study:

• To detect and molecularly characterize a putative new ampelovirus in Vitis vinifera cv. Carnelian.
• To determine the phylogenetic position of the newly identified virus within the Ampelovirus genus.
• To propose a name for the newly discovered grapevine virus.

Main Methods:

• Detection of the virus in symptomatic Carnelian grapevines.
• Complete genome sequencing (13,625 nt) of the putative new ampelovirus.
• Phylogenetic analysis based on complete genome sequences to compare with known ampeloviruses.

Main Results:

• A novel ampelovirus was identified in Vitis vinifera cv. Carnelian exhibiting mild leafroll symptoms.
• The virus genome structure is similar to subgroup I members of the genus Ampelovirus (family Closteroviridae).
• Phylogenetic analyses position this virus as the most distinct member of the GLRaV-4 lineage, separate from GLRaV-4, -5, -6, -9, GLRaV-Pr, and GLRaV-De.

Conclusions:

• The findings indicate the presence of a new ampelovirus species within the family Closteroviridae.
• The proposed provisional name is grapevine leafroll-associated Carnelian virus.
• This discovery expands our understanding of grapevine leafroll-associated virus diversity and evolution.