Curing two predominant viruses occurring in Lentinula edodes by chemotherapy and mycelial fragmentation methods

Previous research has established that Lentinula edodes mycovirus HKB (LeV-HKB) and L. edodes partitivirus 1(LePV1) are major mycoviruses identified in L.edodes germplasm. In this paper, two different methods for curing these two dsRNA mycoviruses, ribavirin treatment and mycelial fragmentation, were evaluated for the first time. Mycelial fragmentation was found to resulted in LeV-HKB- and LePV1-cured fungal strains, whereas ribavirin treatment could eliminate LeV-HKB only. Although no LePV1-cured strain was obtained via ribavirin treatment by the end of the experiment, the relative LePV1 concentration in the eighth successive subcultures was lower than that of the untreated control. The culture features of several virus-cured strains had faster mycelial growth rate and higher colony density than the infected ones. It was also suggested that LeV-HKB infection may affect the pigmentation in plate- and bag-cultivated mycelia of L. edodes strain L135.