17 Mahmoud E. Khalifa Eldessoky S. Dessoky Atef S. Sadik Journal of Animal and Plant Sciences JAPS 20222022/07/30 32 4 1101-1109 1018-7081 NA <p>Several mycoviruses have potential to induce hypovirulence on their fungal pathogens and therefore the interest in mycoviruses has increased in recent years. In the current study, a single double-stranded RNA (dsRNA) molecule of 2531 nts was detected, sequenced and characterized from an Egyptian isolate (D7) of&nbsp;<em>Sclerotinia sclerotiorum</em>&nbsp;fungus. The dsRNA has one open reading frame (ORF), in its positive strand, encoding a protein with conserved motifs characteristic of viral RNA-dependent RNA-polymerases (RdRps). The RdRp encoded by the ORF shares 91.84% identity with that of isolate HC025 of sclerotinia sclerotiorum mitovirus 1 (SsMV1) and consequently it was tentatively named SsMV1-D7. As for previously described mitoviruses, the termini of the (+) strand of SsMV1-D7 RNA could potentially fold into stable secondary structures. Horizontal transmission and virulence experiments showed that SsMV1-D7 is probably responsible for the altered growth and virulence of&nbsp;<em>S. sclerotiorum</em>.</p> dsRNA; Mycovirus; Mitoviridae; Mitovirus; Sclerotinia sclerotiorum; Hypovirulence Pakistan Agricultural Scientists Forum https://thejaps.org.pk/AbstractView.aspx?mid=Biot-20-0065