title: Prevalence and diversity of mycoviruses infecting the plant pathogen Ustilaginoidea virens.
abstract: Rice false smut caused by Ustilaginoidea virens is a destructive disease in many rice-growing areas. Mycoviruses have been described in many fungal species, but there is little information regarding mycoviruses in U. virens. In this study, double-stranded (ds) RNA banding patterns were assessed in 198 wild-type isolates of U. virens obtained from different geographical regions in China. The presence of viral infections was unusually common in U. virens: 188 of the 198 isolates contained dsRNA elements with viral characteristics, and the presence of mixed infections with two or more related or unrelated mycoviruses was commonly detected. The GX-1 isolate contained four dsRNA mycoviruses: Ustilaginoidea virens RNA virus 1 (UvRV1) belonging to Totiviridae, Ustilaginoidea virens RNA virus 4 (UvRV4) belonging to an unclassified family which includes the Curvularia thermal tolerance virus, and the last two probably belonging to Partitiviridae. Biological comparisons of virus-free and infected fungal isolates revealed that UvRV1 strain GX-1 and UvRV4 were likely cryptic, since the infected strains did not show apparent symptoms or debilitation. Northern blotting experiments revealed that UvRV1 strain GX-1 and UvRV4 were frequently found in U. virens, irrespective of the place of origin, and similarly sized dsRNA bands were not always of similar sequence. Thus, our findings suggest that mycoviruses infecting U. virens in China are widespread and highly diverse.
authors.affiliation: The Key Lab of Crop Disease Monitoring and Safety Control in Hubei Province, Huazhong Agricultural University, Wuhan, Hubei 430070, China.
authors.forename: Yinhui
authors.initials: Y
authors.lastname: Jiang
authors.affiliation: The Key Lab of Crop Disease Monitoring and Safety Control in Hubei Province, Huazhong Agricultural University, Wuhan, Hubei 430070, China.
authors.forename: Tingting
authors.initials: T
authors.lastname: Zhang
authors.affiliation: The Key Lab of Crop Disease Monitoring and Safety Control in Hubei Province, Huazhong Agricultural University, Wuhan, Hubei 430070, China.
authors.forename: Chaoxi
authors.initials: C
authors.lastname: Luo
authors.affiliation: The Key Lab of Crop Disease Monitoring and Safety Control in Hubei Province, Huazhong Agricultural University, Wuhan, Hubei 430070, China.
authors.forename: Daohong
authors.initials: D
authors.lastname: Jiang
authors.affiliation: The Key Lab of Crop Disease Monitoring and Safety Control in Hubei Province, Huazhong Agricultural University, Wuhan, Hubei 430070, China.
authors.forename: Guoqing
authors.initials: G
authors.lastname: Li
authors.affiliation: Institute of Plant Protection, Guangxi Academy of Agricultural Sciences, Nanning, Guangxi 530007, China.
authors.forename: Qili
authors.initials: Q
authors.lastname: Li
authors.affiliation: School of Environmental Sciences, University of Guelph, Guelph, ON N1G 2W1, Canada.
authors.forename: Tom
authors.initials: T
authors.lastname: Hsiang
authors.affiliation: The Key Lab of Crop Disease Monitoring and Safety Control in Hubei Province, Huazhong Agricultural University, Wuhan, Hubei 430070, China. Electronic address: junbinhuang@mail.hzau.edu.cn.
authors.forename: Junbin
authors.initials: J
authors.lastname: Huang
mesh_terms: D002681:China; D016000:Cluster Analysis; D006999:Hypocreales / Q000302:isolation & purification / Q000821:virology*; D008958:Models, Molecular; D008969:Molecular Sequence Data; D009690:Nucleic Acid Conformation; D012275:Oryza / Q000382:microbiology; D010802:Phylogeny; D010935:Plant Diseases / Q000382:microbiology; D015995:Prevalence; D012328:RNA Viruses / Q000145:classification* / Q000302:isolation & purification*; D012367:RNA, Viral / Q000235:genetics; D017422:Sequence Analysis, DNA; D017385:Sequence Homology
chemical_list: D012367:RNA, Viral
keywords: Diversity; Mycovirus; Prevalence; Ustilaginoidea virens; dsRNA