SCAR and CAPS markers flanking the Brassica oleracea L. Pp523 downy mildew resistance locus demarcate a genomic region syntenic to the top arm end of Arabidopsis thaliana L. chromosome 1

Abstract

We recently mapped the Pp523 locus that includes a single, dominant gene conferring resistance to downy mildew expressed in adult plants to a 75.1 cm long linkage group on a genetic linkage map of Brassica oleracea L. More recently, we identified a new AFLP marker 2.8 cm downstream from the resistance gene. The five DNA markers within an 8.5 cm region encompassing the Pp523 gene were cloned and sequenced. Three of these markers were transformed into SCARs (sequence characterised amplified regions), however, two among them were monomorphic and were analysed as CAPS (cleaved amplified polymorphic sequence) markers among the mapping population. Searched against genomic databases, the five B. oleracea DNA-marker sequences matched Arabidopsis thaliana L. gene sequences that delimit a conserved syntenic region in the top arm end of chromosome 1 of this last species. Considering the close genetic relatedness between both species, the information on this specific genomic region in A. thaliana is particularly useful for the construction of a fine-scale map of the corresponding genomic region in B. oleracea. The identified SCAR and CAPS markers can be used for marker assisted selection (MAS) in breeding programs aimed at the introgression of the Pp523 resistance locus, allowing the reliable indirect identification of plants harbouring the resistance gene with a margin of error of approximately six in ten-thousand selected plants.

The Pea (Pisum sativum L.) Rogue Paramutation is Accompanied by Alterations in the Methylation Pattern of Specific Genomic Sequences

“…Selective amplifications were performed using 64 primer combinations (Table S3). The excision from gels, re-amplification, and cloning of polymorphic bands were performed as previously described [36].…”

Identification of DNA markers linked to an induced mutated gene conferring resistance to powdery mildew in pea (Pisum sativum L.)

“…ISSR analysis were carried out as described in Farinhó et al (2004), where primer codes and sequences can be found. The conversion of randomly amplified markers into sequence characterised amplified region (SCAR) markers was performed as described in Farinhó et al (2007). The SSR (microsatellite) markers assayed were those mapped by Ek et al (2005).…”

Genome wide identification of NBS-LRR genes in Brassica and their association with disease resistance in Brassica napus

“…For instance, in Australia, outbreaks of downy mildew disease at the early seedling stage have caused losses of canola production (Ge et al, 2008). Several major qualitative resistance loci to downy mildew have been identified in B. rapa and B. oleracea (Farinhó et al, 2007, Carlier et al, 2012. In addition, multiple sources of resistance have been reported in B. napus (Nashaat et al, 1997, Ge et al, 2008.…”

“…In B. oleracea, four resistance loci have been identified: Pp523 on chromosome C8 (Farinhó et al, 2004, Farinhó et al, 2007, Carlier et al, 2011, Carlier et al, 2012, the dominant single locus Ppa3 (Singh et al, 2012), downy mildew resistance locus Dm (Giovannelli et al, 2002) and Alabaça, 2009). In B. rapa, three resistance loci were found, BraDM on chromosome A8 , Yu et al, 2011b, the BrRHP1 locus on chromosome A1 and candidate resistance gene locus RPP13MK on chromosome A9 (Yu et al, 2010).…”

“…(**) The primary and homeologous CRa QTL are overlapping with the primary and homeologous CRb QTL, so they are considered as one primary QTL and one homeologous QTL for both the CRa and CRb locus. (Farinhó et al, 2004, Farinhó et al, 2007, Carlier et al, 2011, Carlier et al, 2012 …”