Novel and diverse mycoviruses co-infecting a single strain of the phytopathogenic fungus Alternaria dianthicola.

Alternaria dianthicola is a pathogenic fungus that causes serious leaf or flower blight on some medicinal plants worldwide. In this study, multiple dsRNA bands in the range of 1.2-10 kbp were found in a Alternaria dianthus strain HNSZ-1, and eleven full-length cDNA sequences of these dsRNA were obtained by high-throughput sequencing, RT-PCR detection and conventional Sanger sequencing. Homology search and phylogenetic analyses indicated that the strain HNSZ-1 was infected by at least nine mycoviruses. Among the nine, five viruses were confirmed to represent novel viruses in the families Hypoviridae, Totiviridae, Mymonaviridae and a provisional family Ambiguiviridae. Virus elimination and horizontal transmission indicated that the (-) ssRNA virus, AdNSRV1, might be associated with the slow growth and irregular colony phenotype of the host fungus. As far as we know, this is the first report for virome characterization of A. dianthus, which might provide important insights for screening of mycovirus for biological control and for studying of the interactions between viruses or viruses and their host.

[Detection of two viruses infecting Pinellia ternata in China].

OBJECTIVE: To study viruses infecting Pinellia ternata in China. METHOD: Symptom observation, DAS-ELISA and RT-PCR detection were applied. RESULT AND CONCLUSION: During a survey in early spring, SMV and CMV were both commonly distributed as main viruses infecting P. ternata collected from different areas in China. But DsMV was the virus which infected P. ternate in natural condition. The infection ratio of cultivated P. ternate by SMV and CMV were 71.4% and 14.3% respectively for 21 samples collected from Ningbo, Zhejiang province; 100% and 44.4% for 18 samples from Xiaoshan, Zhejiang province; 61.9% and 33.3% for 21 samples from Hebei province; 50.0% and 41.7% for 12 samples from Anhui province; 16.7% and 16.7% for 12 samples from Sichuan province; 31.3% and none for 16 samples from Beijing. And the infection ratio of 25 wild samples from different areas of China infected by SMV and CMV were both 20.0%.