Plastid DNA variation in Prunus serotina var. serotina (Rosaceae), a North American tree invading Europe

Black cherry (Prunus serotina) is a tree from North America, where it is often used for economical purposes, whereas it is widespread and invasive in Europe. Plastid DNA variation was first investigated in both its native and invasive ranges using microsatellite loci and sequences of three intergenic spacers (trnT-trnL, trnD-trnT and trnS-trnG). This analysis was focused on P. serotina var. serotina, with the inclusion of samples of closely related taxa. Length variation at a microsatellite locus (ccmp5) and a few sequence polymorphisms were identified among P. serotina samples. Four new primer pairs were then designed to specifically amplify variable regions and a combination of five markers was finally proposed for phylogeographic studies in P. serotina. These loci allow identification of six chlorotypes in P. serotina var. serotina, which may be particularly useful to depict the maternal origins of European invasive populations.