A novel putative member of the family Benyviridae is associated with soilborne wheat mosaic disease in Brazil

Abstract

Soilborne wheat mosaic disease (SBWMD), originally attributed to infections by Soilborne wheat mosaic virus (SBWMV) and Wheat spindle streak mosaic virus (WSSMV), is one of the most frequent virus diseases and causes economic losses in wheat in southern Brazil. This study aimed to characterize molecularly the viral species associated with wheat plants showing mosaic symptoms in Brazil. Wheat leaves and stems displaying mosaic symptoms were collected from different wheat cultivars in Passo Fundo municipality, Rio Grande do Sul State, southern Brazil. Double‐stranded RNA was extracted and submitted to cDNA library synthesis and next‐generation sequencing. No sequences of SBWMV and WSSMV were detected but the complete genome sequence of a putative new member of the family Benyviridae was determined, for which the name wheat stripe mosaic virus (WhSMV) is proposed. WhSMV has a bipartite genome with RNA 1 and RNA 2 organization similar to that of viruses belonging to Benyviridae. WhSMV RNA 1 has a single open reading frame (ORF) encoding a polyprotein with putative viral replicase function. WhSMV RNA 2 has six ORFs encoding the coat protein, the major protein (read‐through), triple gene block movement proteins (TGB 1, 2 and 3) and ORF 6 (hypothetical protein). In addition to the genomic organization and nucleotide and amino acid sequence identities, phylogenetic analyses also corroborated that WhSMV is a virus species of the Benyviridae. However, isolates of WhSMV formed a clade distinct from members of the genus Benyvirus. It was also demonstrated that the plasmodiophorid Polymyxa graminis is associated with wheat roots showing SBWMD symptoms and infected by WhSMV.

Transcriptome Mining Reveals a Spectrum of RNA Viruses in Primitive Plants

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Viroses em trigo no brasil: uma visão histórica

“…Os primeiros relatos da doença são do final da década de 1960de , sendo etiologia viral reportada em 1978de (CAETANO et al 1978. Ao longo dos anos, distintas espécies de vírus foram associadas à doença culminando na identificação de uma nova espécie em 2019 (VALENTE et al 2019).…”

Identification of a Novel Quinvirus in the Family Betaflexiviridae That Infects Winter Wheat

“…In recent years, the RNA sequencing (RNA-seq) analyses of field-grown crops, using next-generation sequencing (NGS) techniques, have enabled a more-detailed view on viral communities in the agroecosystem, often leading to new virus discoveries ( Roossinck et al, 2015 ). Several studies have investigated the virome of wheat and barley plants using deep RNA-seq ( Jo et al, 2018 ; Golyaev et al, 2019 ; Albrecht et al, 2020 ; Hodge et al, 2020 ; Singh et al, 2020 ), and some have identified the novel or uncharacterized wheat-infecting viruses, such as wheat stripe mosaic virus (a tentative benyvirus in the Benyviridae ), wheat yellow striate virus (an alphanucleorhabdovirus in the family Rhabdoviridae ), and European wheat striate mosaic virus (a putative tenuivirus in the family Phenuiviridae ; Liu et al, 2018 ; Valente et al, 2019 ; Somera et al, 2020 ). Nevertheless, there is still very limited information concerning virome or viral agents in the wheat plants that are associated with yellow mosaic disease.…”