biostudies-literatureGuo JMOST | National Key Research and Development Program of China (NKPs)MOST | National Key Research and Development Program of ChinaMOST | National Natural Science Foundation of China (NSFC)MOST | National Natural Science Foundation of Chinae2320572121https://www.ebi.ac.uk/biostudies/studies/S-EPMC11214047biostudies-literatureUnknown121(26)Although most known viruses infecting fungi pathogenic to higher eukaryotes are asymptomatic or reduce the virulence of their host fungi, those that confer hypervirulence to entomopathogenic fungus still need to be explored. Here, we identified and studied a novel mycovirus in <i>Metarhizium flavoviride</i>, isolated from small brown planthopper (<i>Laodelphax striatellus</i>). Based on molecular analysis, we tentatively designated the mycovirus as Metarhizium flavoviride partitivirus 1 (MfPV1), a species in genus <i>Gammapartitivirus</i>, family <i>Partitiviridae</i>. MfPV1 has two double-stranded RNAs as its genome, 1,775 and 1,575 bp in size respectively, encapsidated in isometric particles. When we transfected commercial strains of <i>Metarhizium anisopliae</i> and <i>Metarhizium pingsProceedings of the National Academy of Sciences of the United States of AmericaTransfection of entomopathogenic <i>Metarhizium</i> species with a mycovirus confers hypervirulence against two lepidopteran pests.PMC112140472023YFD140030032001873Liu YJin HGuo JWu NFrancis FWang XZhang PLiu WfalseTransfection of entomopathogenic <i>Metarhizium</i> species with a mycovirus confers hypervirulence against two lepidopteran pests.Although most known viruses infecting fungi pathogenic to higher eukaryotes are asymptomatic or reduce the virulence of their host fungi, those that confer hypervirulence to entomopathogenic fungus still need to be explored. Here, we identified and studied a novel mycovirus in <i>Metarhizium flavoviride</i>, isolated from small brown planthopper (<i>Laodelphax striatellus</i>). Based on molecular analysis, we tentatively designated the mycovirus as Metarhizium flavoviride partitivirus 1 (MfPV1), a species in genus <i>Gammapartitivirus</i>, family <i>Partitiviridae</i>. MfPV1 has two double-stranded RNAs as its genome, 1,775 and 1,575 bp in size respectively, encapsidated in isometric particles. When we transfected commercial strains of <i>Metarhizium anisopliae</i> and <i>Metarhizium pings2024-01-01T00:00:00Z2024 Jun2026-06-03T03:20:15.731Z2025-04-06T22:32:26.534ZS-EPMC112140473888538010.1073/pnas.2320572121