Complete nucleotide sequence of a potato isolate of strain group C of Potato virus Y from 1938

Abstract

The complete genomic sequence of an isolate (PRI-509) of the C strain of Potato virus Y (PVY C ), which was originally isolated from potato in 1938, was elucidated. The genomic RNA of PRI-509 consists of 9699 nucleotides, with the capacity to encode a polyprotein of 3061 amino acids with a molecular mass of 337 kDa. This is the first full-length sequence of a PVY C isolate from potato that belongs to the C1 phylogenetic subgroup, which was previously thought to exclusively contain nonpotato isolates.Potato virus Y (PVY), the type member of the genus Potyvirus, was described for the first time in the early 1930s as the causal agent of a serious disease in potato [26]. PVY is one of the most common viruses of potato (Solanum tuberosum L.) and causes significant economic losses worldwide, especially in the production of seed potatoes. [12,16,24,25].PVY O and PVY C can be distinguished in potato cultivars bearing the resistance genes Ny tbr and Nc [7,25]. PVY C isolates are defined by the typical hypersensitive response they induce in potato cultivars carrying the Nc gene. PVY C causes systemic mosaic or stipple streak symptoms in potato [8] and is generally not considered a serious problem, since many potato cultivars appear to display a hypersensitive response (field resistance) to this strain [6]. A survey in France in 1985 showed an infection rate of less than 5% with PVY C , while for PVY O and PVY N , infection levels of 80 and 12%, respectively, were reported [13]. In the Netherlands, field surveys conducted from 1994 to 2007 showed similar results [28].PVY also causes diseases and production loss in pepper (Capsicum annuum L.) [22], tomato (Solanum lycopersicum L.) and tobacco crops [25]. For some isolates from pepper, a high level of sequence identity to PVY C from potato was found [11,15,22]. Based on biological data, RFLP restrictotypes and coat protein sequence data, these non-potato isolates were proposed to form a genetic cluster separate from the potato isolates [22].The plant virus collection at Plant Research International (PRI) was established in the early 1950s and includes several historical isolates assigned to different PVY strains. The PVY C isolate described in this study (PRI-509) was isolated from the Dutch potato variety 'Zeeuwse Blauwe' in the Netherlands in 1938 [10,23] and was maintained only in potato. It causes a very distinctive pattern of systemic necrotic lines and lesions, known as stipple streak,The nucleotide sequence reported in this article is available under GenBank accession number: EU563512.Electronic supplementary material The online version of this article

Improving Potato virus Y strain nomenclature: lessons from comparing isolates obtained over a 73‐year period

“…Four Australian isolates (ATL1, BL, DEL3, KIP) were in Y O5 , and one each in subgroups Y C1 (CN1) and Y C2 (KIP1). Y C1 is composed mainly of non-potato isolates like CN1, and Y C2 of potato isolates (Moury, 2010;Dullemans et al, 2011;. Interestingly, biologically defined PVY Z isolates (four) were distributed between each of the Y O and Y O5 phylogenetic subgroups, and biologically defined PVY O isolates (five) in Y O5 , PVY C isolates within Y C2 (two), the single PVY D isolate in Y C2 and the single non-potato isolate in Y C1 .…”

“…Biological and phylogenetic PVY C isolates are considered rare in potato compared with PVY O . Moreover, in contrast to the situation with PVY O , PVY C elicits a hypersensitive phenotype giving ‘field resistance’ in most potato cultivars to which its infrequent occurrence has been attributed since the 1940s (Cockerham, , ; Bawden & Kassanis, ; Dullemans et al ., ); a misunderstanding that poor aphid transmissibility was responsible for its infrequent occurrence was due to use of an attenuated, long‐term PVY C stock culture in aphid transmission tests (Kassanis & Govier, ; Jones, , ). In the inoculations here with Australian PVY isolates, KIP1 elicited a hypersensitive phenotype in many more cultivars (10/13) than PVY O isolates BL and DEL3 (3/13), which is therefore inconsistent with PVY O , but consistent with eliciting a hypersensitive phenotype in most potato cultivars.…”

Recombination of strain O segments to HCpro‐encoding sequence of strain N of Potato virus Y modulates necrosis induced in tobacco and in potatoes carrying resistance genes Ny or Nc

“…Tertiary structures were modelled with I‐TASSER as described by Tian and Valkonen () using HCpro sequences of the PVY C isolate PRI509 (GenBank accession no. ) (Dullemans et al ., ) and isolate Adgen () belonging to clade C2 (potato strains), isolate SON41p () belonging to clade 1, and isolate Chile3 () that does not belong to either clade (Moury, ). SON41p has been used to localize the avirulence determinant corresponding to Nc spl (Moury et al ., ).…”

Pest categorisation of potato virus Y (non‐EU isolates)

“…Capsicum spp. (Margaritopoulos et al, 2010), Nicotiana tabacum , Solanum lycopersicum (Aramburu et al, 2006), S. tuberosum (Dullemans et al, 2011) Additional natural hosts may exist PVY-O Capsicum annuum (Ibaba and Gubba, 2011), Nicotiana tabacum , Solanum lycopersicum (Ibaba and Gubba, 2011), S. melongena (Bhat et al, 1999), S. tuberosum (Dullemans et al, 2011) Additional natural hosts may exist…”