Molecular and biological characterization of a recombinant isolate of potato virus Y from Mexico.

An isolate of potato virus Y (PVY), PVY-M3, was subjected to biological characterization on potato indicators and to whole-genome sequencing. PVY-M3 induced a local and systemic hypersensitive resistance (HR) response in potato cultivar Maris Bard expressing the Nz gene while inducing no HR in potato cultivars Desiree and King Edward, carrying Ny and Nc genes, respectively. These HR responses, combined with a lack of vein necrosis in tobacco, clearly defined PVY-M3 as an isolate of the PVY(Z) strain.

Identification of the molecular make-up of the Potato virus Y strain PVY(Z): genetic typing of PVY(Z)-NTN.

Potato virus Y (PVY) strains were originally defined by interactions with different resistance genes in standard potato cultivars. Five distinct strain groups are defined that cause local or systemic hypersensitive responses (HRs) in genetic background with a corresponding N gene: PVY(O), PVY(N), PVY(C), PVY(Z), and PVY(E). The nucleotide sequences of multiple isolates of PVY(O) and PVY(N) differ from each other by ≈8% along their genomes.

Genetic diversity of the ordinary strain of Potato virus Y (PVY) and origin of recombinant PVY strains.

The ordinary strain of Potato virus Y (PVY), PVY(O), causes mild mosaic in tobacco and induces necrosis and severe stunting in potato cultivars carrying the Ny gene. A novel substrain of PVY(O) was recently reported, PVY(O)-O5, which is spreading in the United States and is distinguished from other PVY(O) isolates serologically (i.e.

The helper component proteinase cistron of Potato virus Y induces hypersensitivity and resistance in Potato genotypes carrying dominant resistance genes on chromosome IV.

The Nc(tbr) and Ny(tbr) genes in Solanum tuberosum determine hypersensitive reactions, characterized by necrotic reactions and restriction of the virus systemic movement, toward isolates belonging to clade C and clade O of Potato virus Y (PVY), respectively. We describe a new resistance from S. sparsipilum which possesses the same phenotype and specificity as Nc(tbr) and is controlled by a dominant gene designated Nc(spl).

Complementations and exclusions between mutated versions of a potato virus Y genotype during mixed infections of Nicotiana hosts.

Understanding the processes that have led to the recent prevalence of necrotic genotypes in PVY populations is an important challenge for research programs studying this virus. Non-necrotic PVY(O)-139, necrotic PVY(N)-605 and point mutated versions of PVY(N)-605 (PVY(KRED), PVY(KR) and PVY(ED)), were used in mixtures to inoculate two Nicotiana hosts which express (N. tabacum cv.