Characterization of small RNAs originating from mitoviruses infecting the conifer pathogen Fusarium circinatum

Deep sequencing of small RNAs has proved effective in the diagnosis of mycovirus infections. In this study, the presence of mycoviruses in ten isolates of the phytopathogenic fungus Fusarium circinatum was investigated by high-throughput sequencing (HTS) of small RNAs. The contigs resulting from de novo assembly of the reads were aligned to viral genome sequences. The presence of each mycovirus detected in the isolates was confirmed by RT-PCR analysis with four previously described primer pairs and seven new pairs designed on the basis of sequencing data. The findings demonstrate the potential use of HTS for reconstructing previously identified mitoviruses infecting F. circinatum.