Premise of the study: Microsatellite markers were developed for Isodon longitubus to study the natural hybridization of the species and its congeners. •
Methods and results: A total of 10 primer sets were developed for I. longitubus. From the initial screening, all of 10 loci were polymorphic with five to 19 alleles per locus in the Mt. Ishizuchi population, whereas nine loci were polymorphic with two to 12 alleles per loci in the Toon population. Although one locus was monomorphic at one population, the observed and expected heterozygosity values estimated from 34 I. longitubus samples ranged from 0.273 to 1.000 and from 0.483 to 0.918, respectively. Six primer sets could amplify all three species examined in this study (I. inflexus, I. japonicus, and I. shikokianus). •
Conclusions: The 10 microsatellite markers developed here will be useful in analyzing the population genetic structure of I. longitubus and in studying the natural hybridization between Isodon species.
Keywords: Isodon longitubus; Lamiaceae; microsatellite; polymorphism.