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

Abstract

Yellow mosaic disease in winter wheat is usually attributed to the infection by bymoviruses or furoviruses; however, there is still limited information on whether other viral agents are also associated with this disease. To investigate the wheat viromes associated with yellow mosaic disease, we carried out de novo RNA sequencing (RNA-seq) analyses of symptomatic and asymptomatic wheat-leaf samples obtained from a field in Hokkaido, Japan, in 2018 and 2019. The analyses revealed the infection by a novel betaflexivirus, which tentatively named wheat virus Q (WVQ), together with wheat yellow mosaic virus (WYMV, a bymovirus) and northern cereal mosaic virus (a cytorhabdovirus). Basic local alignment search tool (BLAST) analyses showed that the WVQ strains (of which there are at least three) were related to the members of the genus Foveavirus in the subfamily Quinvirinae (family Betaflexiviridae). In the phylogenetic tree, they form a clade distant from that of the foveaviruses, suggesting that WVQ is a member of a novel genus in the Quinvirinae. Laboratory tests confirmed that WVQ, like WYMV, is potentially transmitted through the soil to wheat plants. WVQ was also found to infect rye plants grown in the same field. Moreover, WVQ-derived small interfering RNAs accumulated in the infected wheat plants, indicating that WVQ infection induces antiviral RNA silencing responses. Given its common coexistence with WYMV, the impact of WVQ infection on yellow mosaic disease in the field warrants detailed investigation.

Discovery and Genome Characterization of a Closterovirus from Wheat Plants with Yellowing Leaf Symptoms in Japan

“…When a small RNA dataset derived from wheat cv. “Kitahonami” infected with a betaflexivirus [ 35 ] or “Chinese Spring” [ 36 ] uninfected with WhCV1 was analyzed, no small RNA read was mapped to the 3′-terminal end of the WhCV1-WL19a negative-strand genomic RNA (data not shown), suggesting that the abundant 22-nt small RNAs were specifically derived from WhCV1 RNAs and probably not from the host plant.…”

Analysis of Wheat Virome in Korea Using Illumina and Oxford Nanopore Sequencing Platforms

“…Wheat viruses continue to pose a major threat to wheat production and global food security [ 32 ]. Recently, various HTS platforms have been utilized for detecting undocumented or newly putative viruses and for complete virome analysis in wheat [ 32 , 33 , 34 , 35 , 36 , 37 , 38 ]. However, no studies have been reported identifying wheat-infecting viruses in Korea; therefore, we aimed to determine the composition of the wheat virome by utilizing field samples from three major domestic wheat-producing regions through two HTS platforms.…”

Molecular characterization of a novel virga-like virus associated with wheat

“…Over the last decade, HTS has been widely applied to plant virology, leading to a signi cant increase in the discoveries of novel plant viruses [13] as well as in wheat new emerging plant viruses are constantly being identi ed [14][15][16]. In our study, the genome organization of TaAVLV1 detected from wheat leaves hasn't evolved to obtain any sequences for encoding any coat protein (CP) or movement protein (MP), but shared a lot of similarity to fungal viruses.…”