Screening transferable microsatellite markers across genus Phalaenopsis (Orchidaceae)

Background: Molecular identification based on microsatellite loci is an important technology to improve the commercial breeding of the moth orchid. There are more than 30,000 cultivars have been enrolled at the Royal Horticultural Society (RHS). In this study, genomic microsatellite primer sets were developed from Phalaenopsis aphrodite subsp. formosana to further examine the transferability of across 21 Phalaenopsis species. Methods and results: Twenty-eight polymorphic microsatellite markers were obtained using the magnetic bead enrichment method, with high transferability of the 21 species of the genus Phalaenopsis, especially in the subgenus Phalaenopsis. The 28 newly developed polymorphic microsatellite markers with high polymorphism information content values. The best and second fit grouping (K) are inferred as two and four by the ΔK evaluation in the assignment test. This result indicates that these microsatellite markers are discernible to subgenus Phalaenopsis. Conclusions: Our results indicate that these new microsatellite markers are useful for delimiting species within genus Phalaenopsis. As expected, the genetic relationships between species of subgenus Phalaenopsis can be well distinguished based on the assignment test. These molecular markers could apply to assess the paternity of Phalaenopsis as well as investigating hybridization among species of genus Phalaenopsis.