New microsatellite markers for Campanula scheuchzeri (Campanulaceae), with cross-amplification in C. rotundifolia1

PREMISE OF THE STUDY We developed new microsatellite primers for the alpine bellflower Campanula scheuchzeri. Allelic polymorphisms will be used to study differentiation along elevation gradients of C. scheuchzeri populations and in the co-occurring sister-species C. rotundifolia in the Alps. METHODS AND RESULTS We analyzed C. scheuchzeri from three high-elevation sites and C. rotundifolia from two low-elevation sites in Switzerland. Campanula scheuchzeri was found to be tetraploid (2n = 68 = 4x), and up to 22 alleles were found per locus and population. Of the 15 polymorphic loci developed for C. scheuchzeri, 10 loci were tested, all of which amplified in C. rotundifolia, with similar amplicon length. Campanula rotundifolia individuals also showed tetraploid signals. CONCLUSIONS We speculate that C. scheuchzeri and C. rotundifolia share a common gene pool and evolve under vicariance. This presents a testable hypothesis that will be evaluated through future work. Our developed primers might also amplify in other related Campanula taxa.