The novel gene Ny-1 on potato chromosome IX confers hypersensitive resistance to Potato virus Y and is an alternative to Ry genes in potato breeding for PVY resistance.
Hypersensitive resistance (HR) is an efficient defense strategy in plants that restricts pathogen growth and can be activated during host as well as non-host interactions. HR involves programmed cell death and manifests itself in tissue collapse at the site of pathogen attack. A novel hypersensitivity gene, Ny-1, for resistance to Potato virus Y (PVY) was revealed in potato cultivar Rywal. This is the first gene that confers HR in potato plants both to common and necrotic strains of PVY. The locus Ny-1 mapped on the short arm of potato chromosome IX, where various resistance genes are clustered in Solanaceous genomes. Expression of HR was temperature-dependent in cv. Rywal. Strains PVYO and PVYN, including subgroups PVYNW and PVYNTN, were effectively localized when plants were grown at 20 degrees C. At 28 degrees C, plants were systemically infected but no symptoms were observed. In field trials, PVY was restricted to the inoculated leaves and PVY-free tubers were produced. Therefore, the gene Ny-1 can be useful for potato breeding as an alternative donor of PVY resistance, because it is efficacious in practice-like resistance conferred by Ry genes.
Szajko
K
K
Plant Breeding and Acclimatization Institute, Platanowa 19, 05831 Młochów, Poland.
Chrzanowska
M
M
Witek
K
K
Strzelczyk-Zyta
D
D
Zagórska
H
H
Gebhardt
C
C
Hennig
J
J
Marczewski
W
W
D001947:Breeding / Q000379:methods; D002874:Chromosome Mapping; D017931:DNA Primers / Q000235:genetics; D017343:Genes, Plant / Q000235:genetics*; D007113:Immunity, Innate / Q000235:genetics*; D010935:Plant Diseases / Q000821:virology*; D017800:Potyvirus; D020133:Reverse Transcriptase Polymerase Chain Reaction; D011198:Solanum tuberosum / Q000235:genetics* / Q000821:virology
D017931:DNA Primers