Supplementary files for "Diversity and impact of single-stranded RNA viruses in Czech <i>Heterobasidion</i> populations" https://doi.org/10.1128/msystems.00506-24

<i>Heterobasidion annosum</i> sensu lato comprises some of the most devastating pathogens of conifers. Exploring virocontrol as a potential strategy to mitigate economic losses caused by these fungi holds promise for the future. In this study, we conducted a comprehensive screening for viruses in 98 <i>H. annosum</i> s.l. specimens from different regions of Czechia aiming to identify viruses inducing hypovirulence. Initial examination for dsRNA presence was followed by RNA-seq analyses using pooled RNA libraries constructed from <i>H. annosum</i> and<i> Heterobasidion parviporum</i>, with diverse bioinformatic pipelines employed for virus discovery. Our study uncovered 25 distinct ssRNA viruses, including two ourmia-like viruses, one mitovirus, one fusarivirus, one tobamo-like virus, one cogu-like virus, one bisegmented narna-like virus and one segment of another narna-like virus, and 17 ambi-like viruses, for which hairpin and hammerhead ribozymes were detected. Coinfections of up to 10 viruses were observed in six Heterobasidion isolates, whereas another six harbored a single virus. Seventy-three percent of the isolates analyzed by RNA-seq were virus-free. These findings show that the virome of Heterobasidion populations in Czechia is highly diverse and differs from that in the boreal region. We further investigated the host effects of certain identified viruses through comparisons of the mycelial growth rate and proteomic analyses and found that certain tested viruses caused growth reductions of up to 22% and significant alterations in the host proteome profile. Their intraspecific transmission rates ranged from 0% to 33%. Further studies are needed to fully understand the biocontrol potential of these viruses in planta.多年异担子菌复合群（Heterobasidion annosum sensu lato）是针叶树最具破坏性的病原菌类群之一。将病毒防治（virocontrol）作为缓解这类真菌引发经济损失的潜在策略，展现出良好的应用前景。本研究对来自捷克不同地区的98份多年异担子菌复合群（H. annosum s.l.）标本开展了全面的病毒筛查，旨在筛选出可诱导宿主弱毒力的病毒。研究首先对双链RNA（dsRNA）的存在情况进行初步检测，随后利用针对多年异担子菌（H. annosum）和细极异担子菌（Heterobasidion parviporum）构建的混合RNA文库开展转录组测序（RNA-seq）分析，并采用多套生物信息学流程进行病毒发掘。本研究共发现25种不同的单链RNA（ssRNA）病毒，包括2株奥米亚病毒属相关病毒（ourmia-like viruses）、1株线粒体病毒（mitovirus）、1株镰孢病毒属病毒（fusarivirus）、1株烟草花叶病毒样病毒（tobamo-like virus）、1株科古病毒样病毒（cogu-like virus）、1株双节段纳达病毒样病毒（bisegmented narna-like virus）以及1株其他纳达病毒样病毒的基因组片段，另有17株双分病毒样病毒（ambi-like viruses），并在这些双分病毒样病毒中检测到发夹状核酶与锤头状核酶。6株异担子菌分离物可同时感染多达10种病毒，另有6株分离物仅携带单一种病毒。经转录组测序分析的分离物中，73%未携带任何病毒。上述结果表明，捷克地区异担子菌种群的病毒组（virome）具有极高的多样性，且与北方地区的病毒组存在显著差异。本研究还通过菌丝生长速率测定与蛋白质组学分析，对部分已鉴定病毒的宿主效应展开了研究，结果显示部分受试病毒可使宿主菌丝生长速率降低最高达22%，并显著改变宿主的蛋白质组图谱。这些病毒的种内传播率介于0%至33%之间。未来仍需开展进一步研究，以全面阐明这些病毒在植株体内的生物防治应用潜力。