Characterization of a Novel Mycovirus from the Phytopathogenic Fungus Botryosphaeria dothidea

Abstract

<i>Botryosphaeria dothidea</i> is, globally, one of the most economically important phytopathogenic fungi worldwide, causing the canker and dieback of fruit trees. An increasing number of viruses infecting <i>B. dothidea</i> have lately been reported, several of which could confer hypovirulence. In this study, isolated from strain ZM170285-1 of <i>B. dothidea</i>, a novel double-stranded RNA (dsRNA) mycovirus, tentatively named Botryosphaeria dothidea partitivirus 2 (BdPV2), was identified well. The BdPV2 harbored three dsRNA segments (1-3) with lengths of 1751, 1568, and 1198 bp, which encoded an RNA-dependent RNA polymerase (RdRp), a capsid protein (CP), and a hypothetical protein of unknown function, respectively. BLASTp searches revealed that the predicted protein sequences of dsRNA1 and dsRNA2 had the highest identities (74.95% and 61.01%) with the corresponding dsRNAs of Penicillium stoloniferum virus S (PsV-S), whereas dsRNA3 shared the highest identity (32.95%) with the dsRNA3 of Aspergillus ochraceous virus 1 (AoV1). Phylogenetic analysis indicated that BdPV2 belonged to the <i>Gammapartitivirus</i> genus and <i>Partitiviridae</i> family. To our knowledge, this is the first report of a <i>Gammapartitivirus</i> in <i>B. dothidea</i>.