Development of SCAR Markers Linked to a Phytophthora fragariae Resistance Gene and Their Assessment in European and North American Strawberry Genotypes

Abstract

<jats:p>Two dominant sequence characterized amplified region (SCAR) markers (linked at 3.0 cM, coupling phase) were constructed for the strawberry (<jats:italic>Fragaria</jats:italic> ×<jats:italic>ananassa</jats:italic> Duch.) gene <jats:italic>Rpf1</jats:italic>. This gene confers resistance to red stele root rot, caused by the soil-born fungus <jats:italic>Phytophthora fragaria</jats:italic>e Hickman var. <jats:italic>fragaria</jats:italic>e. The SCAR markers were developed originally from the sequence of RAPD OPO-16C<jats:sub>(438)</jats:sub> that is linked in repulsion phase to the <jats:italic>Rpf1</jats:italic> allele. This SCAR primer set produced multiple bands in the resistant test progeny and in some of the susceptible progeny; therefore, new SCARs were developed based on the sequence differences among these bands. These new SCARs were linked in coupling phase to the <jats:italic>Rpf</jats:italic> allele and mapped to the same location as the original RAPD OPO-16C<jats:sub>(438)</jats:sub>. The SCAR markers, as well as some additional RAPD markers known to be linked to <jats:italic>Rpf1</jats:italic>, were shown to be highly conserved in linkage to the gene based on examination of 133 European and North American <jats:italic>Fragaria</jats:italic> L. sp. cultivars and breeding selections. These flanking RAPD and SCAR-PCR markers can be used in breeding programs for the selection of red stele (<jats:italic>Rpf1</jats:italic>) resistance.</jats:p>

A genetic linkage map of microsatellite, gene-specific and morphological markers in diploid Fragaria

“…These markers comprised SSR markers (Nourse et al 2002;James et al 2003;Sargent et al 2003;Ashley et al 2003;Hadonou et al 2004a, b), gene-specific markers (Deng and Davis 2001;A. Aharoni, personal communication) and SCAR markers (Davis et al 1995;Haymes et al 2000;Albani et al 2004) that had been previously reported for Fragaria species along with 20 unpublished SSR markers that were retrieved from the GenBank database (Cipriani, unpublished data; GenBank accession nos. BV097098-097117).…”

HaploSNP affinities and linkage map positions illuminate subgenome composition in the octoploid, cultivated strawberry ( Fragaria×ananassa )

“…The mapping studies performed in the cultivated strawberry have highlighted regions of extensive homozygosity in the genomes of modern F. ×ananassa cultivars attributed to repeated cycles of breeding and selection of specific loci, as well as rearrangements between the diploid and octoploid genomes [8,10]. Despite the molecular resources that have been developed for the cultivated strawberry, to date, only a few studies have reported the characterization of traits of economic importance [12][13][14][15][16], one of the main difficulties being finding sufficient numbers of markers to efficiently saturate QTL-containing regions of the genome.…”

Detection of RAPD markers linked to the everbearing gene in Japanese cultivated strawberry

“…However, there are only a few reports on DNA markers affecting traits in the strawberry. In octoploid Fragaria (2n = 56), RAPD markers and sequence characterized amplified region (SCAR) (Paran, and Michelmore 1993) markers linked to a Phytophthora fragariae resistance gene were identified in 1997 and 2000, respectively (Haymes et al. 1997, 2000).…”