Tri-/hexanucleotide microsatellite markers in peach derived from enriched genomic libraries and their application in rosaceae

Sixty-two novel microsatellites with tri- or hexa nucleotide motifs were developed in peach from enriched genomic libraries. Among them, 49, 6 and 7 microsatellites consisted of repeat motifs of trinucleotides, hexanucleotides, and a complex of tri-/hexanucleotides, respectively. The degree of polymorphism of these microsatellites was lower than that of dinucleotide microsatellites. Chromosomal regions of the Prunus genome were identified for 15 microsatellites using a bin mapping strategy with a Prunus reference map. Two of them could be positioned into a new bin. Cross-species amplification was tested for trinucleotide (hexanucleotide) microsatellites within Prunus and more than 90% of them were applicable to the tested species. Amplification across genera was also tested for Malus, Pyrus, Fragaria and Rosa in the family Rosaceae. A total of 40 to 51% of the tested microsatellites were amplified in the other genera examined. Therefore, newly developed microsatellites could be utilized for synteny analysis and construction of genetic linkage maps in Prunus. Conditions for constructing genomic libraries enriched for trinucleotide motifs were also examined.