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In 2014, Physostegia chlorotic moitié virus (PhCMoV) was discovered in Austria in Physostegia virginiana. Subsequent collaborative efforts established a link between the virus and severe fruit symptoms on important crops such as tomato, eggplant, and cucumber across nine European countries. Thereafter, specific knowledge gaps, which are crucial to assess lhe risks PhCMoV can pose for production and how to manage it, needed to be addressed. In this study, the transmission, prevalence, and disease severity of PhCMoV were examined. This investigation led to lhe identification of PhCMoV presence in a new country, Switzerland. Furthermore, our research indicates that the virus was already present in Europe 30 years ago. Bioassays demonstrated PhCMoV can result in up to 100% tomato yield losses depending on the phenological stage of the plant at the lime of infection. PhCMoV was found to naturally infect 12 new host plant species across eight families, extending its host range to 21 plant species across 15 plant families. The study also identified a polyphagous leafhopper (genus Anaceratagallia) as a natural vector of PhCMoV. Overall, PhCMoV was widespread in small-scale diversified vegetable farms in Belgium where tomato is grown in soil under tunnels, occurring in approximately one-ihird of such farms. However, outbreaks were sporadic and were associated al least once with the cultivation in tomato tunnels of perennial plants that can serve as a reservoir host for the virus and its vector. To further explore this phenomenon and manage the virus, studying the ecology of the vector would be beneficial. [ABSTRACT FROM AUTHOR]

A previously uncharacterized torradovirus species infecting potatoes was detected by high-throughput sequencing from field samples from Peru and in customs intercepts in potato tubers that originated from South America in the United States of America and the Netherlands. This new potato torradovirus showed high nucleotide sequence identity to an unidentified isometric virus (SB26/29), which was associated with a disease named potato rugose stunting in southern Peru characterized over two decades ago. Thus, this virus is tentatively named potato rugose stunting virus (PotRSV). The genome of PotRSV isolates sequenced in this study were composed of two polyadenylated RNA segments. RNA1 ranges from 7,086 to 7,089 nt and RNA2 from 5,228 to 5,230 nt. RNA1 encodes a polyprotein containing the replication block (helicase-protease-polymerase), whereas RNA2 encodes a polyprotein cleaved into a movement protein and the three capsid proteins (CPs). Pairwise comparison among PotRSV isolates revealed amino acid identity values greater than 86% in the protease-polymerase (Pro-Pol) region and greater than 82% for the combined CPs. The closest torradovirus species, squash chlorotic leaf spot virus, shares amino acid identities of ∼58 and ∼41% in the Pro-Pol and the combined CPs, respectively. [ABSTRACT FROM AUTHOR]

Forty-seven potato virus A (PVA) isolates from Europe. Australia, and South America's Andean region were subjected to high-throughput sequencing, and 46 complete genomes from Europe (n = 9), Australia = 2), and the Andes (n = 35) obtained. These and 17 other genomes gave alignments of 63 open reading frames 9,180 nucleotides long; 9 were recombinants. The nonrecombinants formed three tightly clustered, almost equidistant phylogroups; A comprised 14 Peruvian potato isolates; W comprised 37 from potato in Peru, Argentina, and elsewhere in the world; and T contained three from tamarillo in New Zealand. When five isolates were inoculated to a potato cuitivar differential, three strain groups (= pathotypes) unrelated to phylogenetic groupings were recognized. No temporal signal was detected among the dated nonrecombinant sequences. but PVA and potato virus Y (PVY) are from related lineages and ecologically similar; therefore, "relative interpretadating" was obtained using a single maximum - likelihood phylogeny of PVA and PVY sequences and PVY's well-supported 157 CE "time to Forty-seven potato virus A (PVA) isolates from Europe. Australia, and South America's Andean region were subjected to high-throughput sequencing, and 46 complete genomes from Europe (n = 9), Australia = 2), and the Andes (n = 35) obtained. These and 17 other genomes gave alignments of 63 open reading frames 9,180 nucleotides long; 9 were recombinants. The nonrecombinants formed three tightly clustered, almost equidistant phylogroups; A comprised 14 Peruvian potato isolates; W comprised 37 from potato in Peru, Argentina, and elsewhere in the world; and T contained three from tamarillo in New Zealand. When five isolates were inoculated to a potato cuitivar differential, three strain groups (= pathotypes) unrelated to phylogenetic groupings were recognized. No temporal signal was detected among the dated nonrecombinant sequences. but PVA and potato virus Y (PVY) are from related lineages and ecologically similar; therefore, "relative interpretadating" was obtained using a single maximum - likelihood phylogeny of PVA and PVY sequences and PVY's well-supported 157 CE "time to Forty-seven potato virus A (PVA) isolates from Europe. Australia, and South America's Andean region were subjected to high-throughput sequencing, and 46 complete genomes from Europe (n = 9), Australia = 2), and the Andes (n = 35) obtained. These and 17 other genomes gave alignments of 63 open reading frames 9,180 nucleotides long; 9 were recombinants. The nonrecombinants formed three tightly clustered, almost equidistant phylogroups; A comprised 14 Peruvian potato isolates; W comprised 37 from potato in Peru, Argentina, and elsewhere in the world; and T contained three from tamarillo in New Zealand. When five isolates were inoculated to a potato cuitivar differential, three strain groups (= pathotypes) unrelated to phylogenetic groupings were recognized. No temporal signal was detected among the dated nonrecombinant sequences. but PVA and potato virus Y (PVY) are from related lineages and ecologically similar; therefore, "relative interpretadating" was obtained using a single maximum - likelihood phylogeny of PVA and PVY sequences and PVY's well-supported 157 CE "time to most common recent ancestor". The PVA datings obtained were supported by several independent historical coincidences. The PVA and PVY populations apparently arose in the Andes approximately 18 centuries ago, and were taken to Europe during the Columbian Exchange, radiating there after the mid-19th century potato late blight pandemic. PVA's phylogroup A population diverged more recently in the Andean region, probably after new cultivars were bred locally using newly introduced Solanum tuberosum subsp. mberosum as a parent. Such cultivars became widely grown, and apparently generated the A x W phylogroup recombinants. Phylogroup A, and its interphylogroup recombinants, might pose a biosecurity risk. [ABSTRACT FROM AUTHOR]