Four distinct isolates of Helminthosporium victoriae virus 190S identified from Bipolaris maydis.

Abstract Helminthosporium victoriae virus 190S (HvV190S) is the type species of the genus Victorivirus under the family Totiviridae. To date, HvV190S has never been found in places outside the USA and has Helminthosporium victoriae as its only know natural host fungus in the field. Here, we report the identification of 4 double-stranded RNA (dsRNA) viruses from Bipolaris maydis in Hubei province of China. Interestingly, the genomes of the 4 viruses show 81.2%-85.5% sequence identities to HvV190S. Their capsid protein (CP) and RNA-dependent RNA polymerase (RdRp) share 95.5-97.9% and 94.6-96.6% amino acid sequence identities to corresponding proteins of HvV190S. Therefore, the 4 viruses, which show 81.8-87.3% pairwise genome sequence identities, should be considered as distinct isolates of HvV190S. Our finding suggests that HvV190S is widely distributed in the world and may infect fungal species other than H. victoriae.