A genetic interval and physical contig spanning the Peronospora parasitica (At) avirulence gene locus ATR1Nd

Fungal Genet Biol. 2003 Feb;38(1):33-42. doi: 10.1016/s1087-1845(02)00515-7.


In Peronospora parasitica (At) (downy mildew), the genetic determinants of cultivar-specific recognition by Arabidopsis thaliana are the Arabidopsis thaliana-recognised (ATR) avirulence genes. We describe the identification of 10 amplified fragment length polymorphism (AFLP) markers that define a genetic mapping interval for the ATR1Nd avirulence allele, the presence of which is perceived by the RPP1Nd resistance gene. Furthermore, we have constructed a P. parasitica (At) bacterial artificial chromosome (BAC) library comprising over 630Mb of cloned DNA. We have isolated 16 overlapping clones from the BAC library that form a contig spanning the genetic interval. BAC sequence-derived markers and a total mapping population of 311 F(2) individuals were used to refine the ATR1Nd locus to a 1cM interval that is represented by four BAC clones and spans less than 250kb of DNA. This work demonstrates that map-based cloning techniques are feasible in this organism and provides the critical foundations for cloning ATR1Nd using such a strategy.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Alleles
  • Arabidopsis / genetics
  • Arabidopsis / microbiology*
  • Chromosomes, Artificial, Bacterial / genetics
  • Cloning, Molecular
  • Contig Mapping
  • DNA / genetics*
  • Genetic Markers
  • Genomic Library
  • Oomycetes / isolation & purification
  • Oomycetes / pathogenicity
  • Physical Chromosome Mapping
  • Phytophthora / genetics*
  • Phytophthora / pathogenicity


  • Genetic Markers
  • DNA