Résumé
The complex Potato virus Y classification, including groups (PVY
N and PVY
O) and variants (PVY
NTN and PVY
N-W), is based mainly on biological properties of isolates. Published PVY detection tools targeting markers not associated with biological properties could fail to assign correctly isolates in the current classification. To improve PVY detection tools, a single nucleotide polymorphism (SNaPshot) detection assay was developed. The technique was adapted to target the T/C
9259, A/C
2271, G/C
8573 and A/G
2213 PVY polymorphic nucleotides. The “TAGA”, “CCCG”, “CACA” and “CAGA” four-digit codes associated with tested samples allowed identification of PVY
N, PVY
O, PVY
N-W and PVY
NTN isolates, respectively. The PVY SNaPshot procedure is efficient and reliable for PVY detection and characterization in samples containing as few as 10
2 viral RNA copies. Moreover, PVY group assignment is possible for fractions containing only 10 copies of a PVY RNA genome. Finally, the SNaPshot assay allows PVY
N/PVY
O dual characterization for mixed samples containing PVY
N/PVY
O quantity ratios in the range of 0.1–10. This innovative SNaPshot tool improved clearly PVY diagnostic assays described previously by targeting simultaneously major functional markers and sequence unlinked to biological properties used separately in PVY detection tools available currently.