Identification of Fusarium proliferatum chrysovirus 1 and its biocontrol activity of phytopathogenic Fusarium species

Fusarium proliferatum , a pathogenic fungus that causes root rot, poses a significant threat to the yield and quality of Salvia miltiorrhiza . This study introduces Fusarium proliferatum Chrysovirus 1 (FpCV1), a novel mycovirus isolated from strain RZJJ28. FpCV1 consists four double-stranded RNA segments (FpCV1-1 to FpCV1-4), each encoding an open reading frame (ORF). Phylogenetic analysis, corroborated by BLASTp comparison and multiple sequence alignment, identified FpCV1 as a novel member of the genus Betachrysovirus within the family Chrysoviridae . Pathogenicity assays revealed that FpCV1 attenuates the virulence of F. proliferatum . Notably, FpCV1 can be horizontally transmitted to other Fusarium pathogens of S. miltiorrhiza root rot, reducing their virulence. Furthermore, FpCV1-carrying strain RZJJ28 has good potential as a biocontrol agent for the control of S. miltiorrhiza root rot. Additionally, FpCV1 can be also transferred to the pathogen F. oxysporum , which causes Fusarium wilt, thereby inducing hypovirulent effect. This report provides new insights and resources for the ecofriendly management of root rot disease in S. miltiorrhiza and potentially other Chinese medicinal plants. It also opens up the possibility of using one mycovirus (such as FpCV1) to control a variety of plant diseases caused by Fusarium species.