Biological and molecular characterization of a recombinant isolate of potato virus y associated with a tomato necrotic disease occurring in Italy

T. Mascia, M.M. Finetti-Sialer, F. Cillo, D. Gallitelli
doi: 10.4454/jpp.v92i1.22
The biological and molecular characterization of a Potato virus Y (PVY) isolate, denoted PVYC-to, associated with a necrotic phenotype of tomato plants grown in the province of Foggia (Apulia, southern Italy) is reported. The fully sequenced PVYC-to genome consists of 9,691 nucleotides and is 94,8% similar to that of PVY LYE84.2, an isolate of the PVYC strain group. Using programs in RDP package, a putative recombination breakpoint was identified at approximately nucleotide position 2056 to 2632, corresponding to the HC-Pro/P3 coding region. The event seems to represent an introgression of a PVYO strain group sequence and, in particular, of PVY-OZ, which is a non recombinant isolate of the O lineage. From this analysis PVYC-to appeared to be a recombinant isolate. The virus has a very weak infectivity in pepper and possesses a CP coding region characterised by a PVYC2 restrictotype. Our results seem to support the hypothesis that PVYC-to is a recombinant isolate of the PVYC2 strain group.`