High-Throughput Sequencing Reveals Cyclamen persicum Mill. as a Natural Host for Fig Mosaic Virus.

Toufic Elbeaino (1) , Armelle Marais (2) , Chantal Faure (2) , Elisa Trioano (3) , Thierry T. Candresse (2) , Giuseppe Parrella (3)

1 CIHEAM-IAMB - Centre International de Hautes Etudes Agronomiques Méditerranéennes - Institut Agronomique Méditerranéen de Bari
2 BFP - Biologie du fruit et pathologie
3 CNR - National Research Council of Italy | Consiglio Nazionale delle Ricerche

In a search for viral infections, double-stranded RNA (dsRNA) were recovered from a diseased cyclamen (Cyclamen persicum Mill.) accession (Cic) and analyzed by high-throughput sequencing (HTS) technology. Analysis of the HTS data showed the presence of Fig mosaic emaravirus (FMV) in this accession. The complete sequences of six FMV-Cic RNA genomic segments were determined from the HTS data and using Sanger sequencing. All FMV-Cic RNA segments are similar in size to those of FMV from fig (FMV-Gr10), with the exception of RNA-6 that is one nucleotide longer. The occurrence of FMV in cyclamen was investigated through a small-scale survey, from which four plants (out of 18 tested) were found RT-PCR positive. To study sequence variations of cyclamen isolates of FMV, RT-PCR products generated through the amplification of the partially RNA-dependent RNA polymerase (RdRp, RNA-1), glycoprotein (GP, RNA-2), and nucleocapsid (NCP, RNA-3) genes were explored. The nucleotide sequence identities for cyclamen isolates ranged between 86% and 99% in RNA-1, 93% and 99% in RNA-2, and 98% and 99% in RNA-3, while lower identity levels were observed with the sequences of fig isolates. Based on the phylogenetic tree obtained with a 304-nt fragment of RNA3, all FMV isolates from cyclamens were assigned to a single cluster close to fig isolates from the Mediterranean. FMV was graft-transmitted to healthy cyclamens eliciting symptoms similar to those observed in the Cic accession, thus suggesting a causal role of FMV in the symptoms that prompted the investigation. This is the first report of FMV in a non-fig host, Cyclamen persicum, a finding that may help in the control of the mosaic and mosaic-like diseases of fig and cyclamen, respectively.

Mots clés: Fig mosaic emaravirus; high-throughput sequencing

Mots clés: cyclamen

Domaines: Phytopathologie et phytopharmacie; Virologie

Toufic Elbeaino, Armelle Marais, Chantal Faure, Elisa Trioano, Thierry T. Candresse, et al.. High-Throughput Sequencing Reveals Cyclamen persicum Mill. as a Natural Host for Fig Mosaic Virus.. Viruses, 2018, 10 (12), pp.684. ⟨10.3390/v10120684⟩. ⟨hal-02621862⟩