title: A rapid genotyping method for an obligate fungal pathogen, Puccinia striiformis f.sp. tritici, based on DNA extraction from infected leaf and Multiplex PCR genotyping.
abstract: BACKGROUND
  Puccinia striiformis f.sp. tritici (PST), an obligate fungal pathogen causing wheat yellow/stripe rust, a serious disease, has been used to understand the evolution of crop pathogen using molecular markers. However, numerous questions regarding its evolutionary history and recent migration routes still remains to be addressed, which need the genotyping of a large number of isolates, a process that is limited by both DNA extraction and genotyping methods. To address the two issues, we developed here a method for direct DNA extraction from infected leaves combined with optimized SSR multiplexing.
  
  
  RESULTS
  We report here an efficient protocol for direct fungal DNA extraction from infected leaves, avoiding the costly and time consuming step of spore multiplication. The genotyping strategy we propose, amplified a total of 20 SSRs in three Multiplex PCR reactions, which were highly polymorphic and were able to differentiate different PST populations with high efficiency and accuracy.
  
  
  CONCLUSIONS
  These two developments enabled a genotyping strategy that could contribute to the development of molecular epidemiology of yellow rust disease, both at a regional or worldwide scale.
authors.affiliation: UMR1290 BIOGER-CPP, INRA-AgroParisTech, BP01, 78850 Thiverval-Grignon, France. sajid.ali@grignon.inra.fr.
authors.forename: Sajid
authors.initials: S
authors.lastname: Ali
authors.forename: Angélique
authors.initials: A
authors.lastname: Gautier
authors.forename: Marc
authors.initials: M
authors.lastname: Leconte
authors.forename: Jérôme
authors.initials: J
authors.lastname: Enjalbert
authors.forename: Claude
authors.initials: C
authors.lastname: de Vallavieille-Pope