BRIEF REPORT Rubus canadensis virus 1, a novel betaflexivirus identified in blackberry Nina Abou Ghanem-Sabanadzovic • Ioannis E. Tzanetakis • Sead Sabanadzovic Received: 8 July 2012 / Accepted: 9 August 2012 / Published online: 6 October 2012 Ó Springer-Verlag Wien 2012 Abstract Flexuous filaments, resembling flexivirus viri- ons, were observed in partially purified blackberry prepa- rations showing mild virus-like symptoms. Further tests revealed the presence of a novel betaflexivirus that is phylogenetically related to foveaviruses. The putative virus-encoded proteins shared limited similarity with orthologs of known members of the genus, indicating that the virus, provisionally named Rubus canadensis virus 1 (RuCV-1), represents a novel member of the taxon. Results of a survey in several U.S. states suggest that RuCV-1 is not widespread in the blackberry germplasm. Keywords Rubus canadensis Á Blackberry Á Virus Á Betaflexiviridae Blackberries and related berry fruit species in the genus Rubus are susceptible to more than 30 known viruses and several virus-like agents, many of which are associated with a new disorder referred to as blackberry yellow vein disease (BYVD) [10]. Members of several novel virus species have been identified recently in plants displaying BYVD symptoms (Sabanadzovic and Tzanetakis, unpub- lished), including a new foveavirus, the subject of this communication. Flexiviruses (members of the families Alpha-, Beta- and Gammaflexiviridae) from many plants and fungi have been reported [1]. Members of the genus Foveavirus (family Betaflexiviridae) are characterized by flexuous particles that are 800 nm to over 1,000 nm long and 12-15 nm in diameter, have narrow host ranges, and infect dicotyle- donous woody plants [1, 9]. No vector is known for members of any of the currently recognized species of this genus. A new blackberry virus, referred to as Rubus canadensis virus 1 (RuCV-1) was characterized at the biological and molecular level. In addition, detection pro- tocols have been developed and used to access the presence of the virus in all major fresh-blackberry-producing areas in the United States. A smooth blackberry (Rubus canadensis) plant displaying BYVD-like symptoms (transient mild mottling and vein chlorosis) was used as the source for RuCV-1 characteriza- tion. The sample, collected at Balsam Mountain in the Great Smoky Mountains National Park, North Carolina, was des- ignated as BM-01 and tested by DAS-ELISA using anti- bodies specific for raspberry bushy dwarf virus (RBDV), tobacco ringspot virus (TRSV), tomato ringspot virus (ToRSV), tomato spotted wilt virus (TSWV), impatiens necrotic spot virus (INSV), arabis mosaic virus (ArMV), and cucumber mosaic virus (CMV), and it was also analyzed using the ‘‘general’’ potyvirus test (Agdia Inc.). The nucleotide sequence presented in this paper has been deposited in the GenBank database under accession number JX277553. Electronic supplementary material The online version of this article (doi:10.1007/s00705-012-1484-7) contains supplementary material, which is available to authorized users. N. Abou Ghanem-Sabanadzovic Institute for Genomics, Biocomputing and Biotechnology, Mississippi State University, Mississippi State, MS 39762, USA I. E. Tzanetakis Division of Agriculture, Department of Plant Pathology and Cell and Molecular Biology Program, University of Arkansas, Fayetteville, AR, USA S. Sabanadzovic (&) Department of Biochemistry, Molecular Biology, Entomology and Plant Pathology, Mississippi State University, Mississippi State, MS 39762, USA e-mail: ssabanadzovic@entomology.msstate.edu; ss501@msstate.edu 123 Arch Virol (2013) 158:445–449 DOI 10.1007/s00705-012-1484-7