Detection of RNA Mycoviruses in Wild Strains of Lentinula edodes in Korea

Kim Eunjin¹ Park Mi-Jeong ¹ Jang Yeongseon^1,* Ryoo Rhim ¹ Kang-Hyeon Ka¹

¹Forest Microbiology Division, Forest Bioresources Department, National Institute of Forest Science, Suwon, 16631, Korea

Abstract

In general, mycoviruses remain latent and rarely cause visible symptoms in fungal hosts; however, some viral infections have demonstrated abnormal mycelial growth and fruiting body development in commercial macrofungi, including Lentinula edodes. Compared to other cultivated mushrooms, L. edodes is more vulnerable to viral infections as it is still widely cultivated under near-natural conditions. In this study, we investigated whether Korean wild strains of L. edodes were infected by RNA mycoviruses that have previously been reported in other parts of the world (LeSV, LePV1, LeV-HKB, LeNSRV1, and LeNSRV2). Using specific primer sets that target the RNA-dependent RNA polymerase genes of each of the RNA mycovirus, reverse transcription-polymerase chain reaction (RT-PCR) was used to detect viral infection. Viral infection was detected in about 90% of the 112 wild strains that were collected in Korea between 1983 and 2020. Moreover, multiple infections with RNA mycoviruses were detected in strains that had normal fruiting bodies. This work contributes to our understanding of the distribution of RNA mycoviruses in Korea and the impact of multiple viral infections in a single strain of L. edodes.

Figures & Tables

Fig. 1. Reverse transcription-polymerase chain reaction (RT-PCR) detection of viral infection from 112 wild strains of . Specific primer sets targeting RNAdependent RNA polymerase genes of each RNA mycovirus were adopted for RT-PCR. Numbers represent each of the wild strains. Amplification of the β -tubulin gene was used as the positive control to confirm the RNA extraction.