Towards the Forest Virome: High-Throughput Sequencing Drastically Expands Our Understanding on Virosphere in Temperate Forest Ecosystems

Abstract

Thanks to the development of HTS technologies, a vast amount of genetic information on the virosphere of temperate forests has been gained in the last seven years. To estimate the qualitative/quantitative impact of HTS on forest virology, we have summarized viruses affecting major tree/shrub species and their fungal associates, including fungal plant pathogens, mutualists and saprotrophs. The contribution of HTS methods is extremely significant for forest virology. Reviewed data on viral presence in holobionts allowed us a first attempt to address the role of virome in holobionts. Forest health is dependent on the variability of microorganisms interacting with the host tree/holobiont; symbiotic microbiota and pathogens engage in a permanent interplay, which influences the host. Through virus–virus interplays synergistic or antagonistic relations may evolve, which may drastically affect the health of the holobiont. Novel insights of these interplays may allow practical applications for forest plant protection based on endophytes and mycovirus biocontrol agents. The current analysis is conceived in light of the prospect that novel viruses may initiate an emergent infectious disease and that measures for the avoidance of future outbreaks in forests should be considered.

Expanding the environmental virome: Infection profile in a native rainforest tree species

“…Therefore, this can impact the amplification effects arising from increased transmissibility among hosts or dilution effects of infections in agricultural environments or in natural ecosystems ( Keesing et al, 2006 ; Keesing and Ostfeld, 2021 ; Susi and Laine, 2021 ). Interestingly, we identified C. brasiliensis putative viruses related to two different families that have species described to infect different plant hosts of forest trees or crops, i.e., Ilarvirus and Mitovirus ( Pallas et al, 2013 ; Rumbou et al, 2021 ). Of note, the highest diversity of these virus sequences was observed in reproductive organs.…”

“…Understanding how evolutionary forces act in distinct environments, together with the anthropic influence on the emergence of diseases, can provide knowledge to forecast and avert alterations in natural ecosystems that cause crop damage ( Lefeuvre et al, 2019 ). The advances in plant virology are needed mainly for forest tree species that have a current few viral diversity data in their respective forest ecosystems ( Rumbou et al, 2021 ).…”

New Insights on the Integrated Management of Plant Diseases by RNA Strategies: Mycoviruses and RNA Interference

“…In recent years, the emergence of high-throughput sequencing technologies has made possible the identification of an unexpected number of new mycoviruses among fungi ( Table 1 ), a trend expected to continue in the future [ 5 , 36 , 37 , 38 ]. This stream of new findings is improving our understanding of the evolution and diversity of viruses.…”

Multiplex Detection of Pleurotus ostreatus Mycoviruses

“…It is very difficult to identify and characterize new mycoviruses using traditional methods. In recent years, high-throughput sequencing technologies were gradually used for exploration and identification new mycoviruses among fungi [ 5 , 6 ]. The mycovirus was first found and isolated in the diseased mushrooms of Agaricus bisporus [ 7 ].…”