Development of a SNP marker assay for the Lr67 gene of wheat using a genotyping by sequencing approach uri icon

abstract

  • The recently characterised and mapped adult plant resistance gene Lr67 contributes to the breeding of durable resistance against multiple fungal pathogens of wheat. Lack of tightly linked markers has so far prevented widespread use of Lr67 in breeding programmes. Exhaustive screening of available SSR markers and 9,000 gene-associated SNPs using bulk segregant analysis yielded several linked markers but none close enough to the gene for routine breeding applications. In contrast, genotyping by sequencing identified several better-linked SNP-based markers that were converted into single-marker KASPar assays. Marker csSNP856 co-segregated with Lr67 in two mapping populations and was significantly associated with stripe rust resistance in an association mapping population of 972 wheat lines. High frequency (43 %, 29/66) of the Lr67-associated SNP allele in landraces from the Indian subcontinent suggests the origin of Lr67 from this region. While marker csSNP856 is not diagnostic for the presence of Lr67, it represents a significant step towards assisting the transfer of this adult plant resistance gene into elite germplasm via marker-assisted breeding.

publication date

  • 2014
  • 2014