Archives of Virology

, 153:1263 | Cite as

Molecular characterization of Lolium latent virus, proposed type member of a new genus in the family Flexiviridae

  • Anna Maria Vaira
  • Clarissa J. Maroon-Lango
  • John Hammond
Original Article


Lolium latent virus (LoLV) was recently detected in the USA for the first time in ryegrass hybrids (Lolium perenne × Lolium multiflorum). The genome of one USA isolate, LoLV-US1, has now been fully sequenced. The positive strand genomic RNA is 7674 nucleotides (nt) long and is organized in five open reading frames (ORFs) encoding the replication-associated protein, the movement-associated triple gene block proteins and the coat protein (CP). The genome organization is similar to that of viruses in the genera Potexvirus and Foveavirus; however, analysis of the complete LoLV genomic sequence, phylogenetic analyses of the deduced amino acid (aa) sequences of the polymerase and the CP, presence of a putative ORF 6, and the in vivo detection of two CPs in equimolar amounts, highlight features peculiar to LoLV. These characteristics indicate that LoLV forms a monotypic group separate from existing genera and unassigned species within the family Flexiviridae, for which we propose the genus name Lolavirus. One-step RT-PCR was developed for quick and reliable LoLV detection.



We would like to thank Scott Warnke, Ruhui Li and Hyoun-Sub Lim for helpful discussions and Mike Reinsel for invaluable technical assistance.


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Copyright information

© Springer-Verlag 2008

Authors and Affiliations

  • Anna Maria Vaira
    • 1
    • 3
  • Clarissa J. Maroon-Lango
    • 2
  • John Hammond
    • 3
  1. 1.Istituto di Virologia Vegetale, CNRTorinoItaly
  2. 2.Plant Germplasm Quarantine Program, PPQ-PHP, USDA-APHISBeltsvilleUSA
  3. 3.Floral and Nursery Plants Research Unit, USDA-ARS, US National Arboretum, B-010ABeltsvilleUSA

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