Botrytis cinerea is the fungus responsible for grey mould on a wide range of plant species, both in the field and postharvest, resulting in heavy yield losses. Several mycoviruses are known to infect fungal plant pathogens and they might represent a source of variation in the fungal populations. In this study, a metagenomic approach was applied to obtain a comprehensive characterization of the mycovirome in a collection of 60 B. cinerea isolates. High-throughput Illumina sequencing of double-stranded (ds)RNAs extracted from 12 pools of isolates generated about 64 million of high-quality short sequence single reads (50 bp). Contigs obtained through de novo assembly were analysed by sequence similarity to identify putative mycoviral sequences. A great abundance and diversity of mycoviruses was found. A total of 22 different viruses were identified, at different frequencies, in one or more of the analysed pools. These mostly included dsRNA and positive-sense (+) single-stranded (ss) RNA viruses. Among dsRNA viruses, two viruses in the family Partitiviridae, a victorivirus in the family Totiviridae, a virus in the family Quadriviridae, and three unclassified viruses were identified. (+)ssRNA viruses included seven mitoviruses in the family Mitoviridae, three hypoviruses in the f amily Hypoviridae, a fusarivirus in the proposed family Fusariviridae, Botrytis virus F in the family Gammaflexiviridae, a virus in the family Endornaviridae, and an umbra-like mycovirus in the family Tombusviridae. Botrytis cinerea mymonavirus 1 in the family Mymonaviridae was the only negative-sense (-)ssRNA virus found in the analysed isolates. For eight mycoviruses selected as putatively associated to host hypovirulence, the presence of the viral sequences was checked by RT-PCR in 28 individual B. cinerea isolates, revealing single or multiple viral infections. These findings will serve as a basis for further studies aimed at investigating the complex virus–host and virus–virus interactions and at exploring the potential use of mycoviruses as biocontrol agents against grey mould.
The mycovirome of the grey mould fungus Botrytis cinerea
De Miccolis Angelini R. M.
;Rotolo C.;Distante S.;Rotondo P. R.;Pollastro S.;Faretra F.
2023-01-01
Abstract
Botrytis cinerea is the fungus responsible for grey mould on a wide range of plant species, both in the field and postharvest, resulting in heavy yield losses. Several mycoviruses are known to infect fungal plant pathogens and they might represent a source of variation in the fungal populations. In this study, a metagenomic approach was applied to obtain a comprehensive characterization of the mycovirome in a collection of 60 B. cinerea isolates. High-throughput Illumina sequencing of double-stranded (ds)RNAs extracted from 12 pools of isolates generated about 64 million of high-quality short sequence single reads (50 bp). Contigs obtained through de novo assembly were analysed by sequence similarity to identify putative mycoviral sequences. A great abundance and diversity of mycoviruses was found. A total of 22 different viruses were identified, at different frequencies, in one or more of the analysed pools. These mostly included dsRNA and positive-sense (+) single-stranded (ss) RNA viruses. Among dsRNA viruses, two viruses in the family Partitiviridae, a victorivirus in the family Totiviridae, a virus in the family Quadriviridae, and three unclassified viruses were identified. (+)ssRNA viruses included seven mitoviruses in the family Mitoviridae, three hypoviruses in the f amily Hypoviridae, a fusarivirus in the proposed family Fusariviridae, Botrytis virus F in the family Gammaflexiviridae, a virus in the family Endornaviridae, and an umbra-like mycovirus in the family Tombusviridae. Botrytis cinerea mymonavirus 1 in the family Mymonaviridae was the only negative-sense (-)ssRNA virus found in the analysed isolates. For eight mycoviruses selected as putatively associated to host hypovirulence, the presence of the viral sequences was checked by RT-PCR in 28 individual B. cinerea isolates, revealing single or multiple viral infections. These findings will serve as a basis for further studies aimed at investigating the complex virus–host and virus–virus interactions and at exploring the potential use of mycoviruses as biocontrol agents against grey mould.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
