Selection of DNA markers for detection of extreme resistance to potato virus Y in tetraploid potato (Solanum tuberosum L.) F1 progenies

Abstract

Marker-assisted selection is progressively introduced into potato breeding especially in the case of monogenically inherited traits. Varieties and clones with extreme resistance to potato virus Y (PVY) from German, Hungarian, Polish, Dutch and Slovak breeding programmes were used as female parents in 6 crosses. F1 progenies were subjected to the bulk segregant analysis. Polymerase chain reaction (PCR) based markers for Rysto and Ry adg viral resistance alleles were used for the evaluation of varieties, clones and seedlings of F1 progenies. All resistant F 1 genotypes were reliably identified using three molecular markers, STM0003, GP122718 and GP122406, associated with the Rysto allele. No genotype corresponded with phenotypic data and Ryadg markers. Ryadg and three selected Rysto markers were applied to 40 genotypes from an in vitro gene bank and 14 genotypes were recognized to have Rysto and none of them possessed Ry adg. Indirect selection is based on DNA polymorphism linked to the extreme resistance to PVY resulting in error when polymorphism is not conserved in all genetic backgrounds. A failure to detect extreme resistance to PVY using the Rysto markers in variety Santé, resistant progeny of variety Santé and clone Y01-30 may be linked to recombination events or different Solanum stoloniferum background.