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Barley yellow mosaic virus (BaYMV) and Barley mild mosaic virus (BMMV) are two closely related bymoviruses causing significant yield losses to barley in Europe and East Asia. In the present study we detected both viruses and Soil-borne wheat mosaic virus (SBWMV) by DAS-ELISA from field samples collected in Iranian provinces. Moreover, we obtained and sequenced a 971 bp long fragment that included the coat protein coding region of eight Iranian isolates of BaYMV. Phylogenetic analysis of BaYMV coat protein nucleotide sequences previously published shows a separation of Asian and European isolates into two main groups. Surprisingly, Iranian isolates formed a minor cluster within the European group. Alignment of coat protein amino acid sequences confirmed that Iranian BaYMV isolates were more similar to European than to Asian isolates. Further studies are necessary to characterize the molecular and, in particular, the biological properties of Iranian BaYMV isolates in order to evaluate and limit losses on cereal production in the country [ABSTRACT FROM AUTHOR]

Bean yellow mosaic virus (BYMV) is an economic potyvirus with worldwide distribution and a broad host range. Recently, phylogenetic studies of BYMV isolates have indicated the importance of comparing the full genome sequences to obtain a reliable classification. However, most available isolates in public databases are partially sequenced, and virologists continue to prefer partial genomes or individual genes for phylogenetic studies. As such, to avoid unbiased classification, phylogenetic studies should be based on either phylogenetic gene markers or a multigene dataset instead of just one random gene. In the present study, we sequenced the full genome of a BYMV isolate collected from an Iranian faba bean field using the Illumina Novaseq 6000 platform. The phylogenetic analysis revealed that the Iranian isolate is closely related to three isolates originating from faba bean fields in Japan, Australia and Germany. To identify the phylogenetic markers of BYMV, the topology distance between reconstructed trees based on individual genes and the whole genome was calculated using topology congruence tests considering only the topology of the compared trees and a character congruence test taking into account the characters, tree topology and estimated bootstrap support value. Accordingly, nuclear inclusion proteins a and b (NIa and NIb) and viral protein genome linked (VPg) were selected as evolutionary markers which can be used as appropriate representations of the full genome in phylogenetic studies. Furthermore, supermatrix approach was used to compare all BYMV isolates that have been fully or partially sequenced. The results demonstrate that all submitted BYMV strains can be divided into 10 main monophyletic clades with high bootstrap values; these are named BYM-1 through BYM-10 to avoid confusion with previously introduced nomenclature. Moreover, the results reveal that clustering based on phylogenetic analysis and their original host is not completely consistent, which supports recent phylogenetic studies based on available whole genome sequences. • Finding the phylogenetic markers of BYMV. • NIb, NIa and VPg have been selected as the evolutionary markers for phylogenetic studies of BYMV isolates. • All publicly available BYMV isolates can be divided into 10 main clades (BYM1-BYM10) with high bootstrap support value. • Clustering of BYMV isolates based on phylogenetic analysis and their original hosts is not completely consistent. [ABSTRACT FROM AUTHOR]

Bermuda grass with mosaic symptoms have been found in many parts of Iran. No serological correlation was observed between two isolates of this filamentous virus and any of the members of the family Potyviridae that were tested. Aphid transmission was demonstrated at low efficiency for isolates of this virus, whereas no transmission through seed was observed. A DNA fragment corresponding to the 3' end of the viral genome of these two isolates from Iran and one isolate from Italy was amplified and sequenced. A BLAST search showed that these isolates are more closely related to Spartina mottle virus (SpMV) than to any other virus in the family Potyviridae. Specific serological assays confirmed the phylogenetic analysis. Sequence and phylogenetic analysis suggested that these isolates could be considered as divergent strains of SpMV in the proposed genus Sparmovirus.