Prevalence and species diversity of dsRNA mycoviruses from Beauveria bassiana strains in the China's Guniujiang nature

We investigated the prevalence and species diversity of dsRNA mycoviruses in Beauveria bassiana isolates from the China's Guniujiang Nature Preserve. Among the 28 isolates analyzed, electropherotyping revealed viral infections in 28.6 % (8 out of 28) of the isolates. Metatranscriptomic identification and RT-PCR confirmed the presence of six putative virus species, including two novel species: Beauveria bassiana victorivirus 2 (BbV-2) and Beauveria bassiana bipartite mycovirus 2 (BbBV-2). Four previously characterized mycoviruses were also identified: Beauveria bassiana polymycovirus 4 (BbPmV4), Beauveria bassiana partitivirus 1 (BbPV-1), Beauveria bassiana bipartite mycovirus 1 (BbBV-1), and Beauveria bassiana chrysovirus 2 (BbCV-2). BbPmV4 was found to be the prevailing mycovirus among the infected isolates, and three isolates showed co-infection with both BbPmV4 and BbBV-2. This study enhances our understanding of fungal viral taxonomy and diversity, providing insights into mycovirus infections in B. bassiana populations in China's Guniujiang Nature Preserve. Furthermore, the study on the diversity of B. bassiana viruses lays the foundation for recognizing fungal viruses as potential enhancers of biocontrol agents.