Development and characterization of EST-SSR markers in an East Asian temperate plant genus Diabelia (Caprifoliaceae)

A set of expressed sequence tag (EST) simple sequence repeat (SSR) markers were developed and characterized using next-generation sequencing technology for the genus Diabelia (Caprifoliaceae). De novo assembly of RNA-seq reads resulted in 58 669 contigs with the N50 length of 1211 bp. A total of 2746 contigs were identified to harbor SSR motifs, of which 48 primer pairs were designed and 11 were shown to be polymorphic across three morphospecies of Diabelia. When evaluated with 30 individuals, the number of alleles per locus ranged from 2 to 11 and the expected heterozygosity varied from 0.399 to 0.873, respectively. Distance-based clustering indicated that the EST-SSR markers can provide sufficient power to distinguish the three species (or populations). These markers will be useful for evaluating the range-wide genetic diversity of each species and examining genetic divergence and gene flow between the three species.