Genetic and epigenetic differentiation between natural Betula ermanii (Betulaceae) populations inhabiting contrasting habitats

Disentangling the molecular mechanisms of adaptation in natural plant populations in response to different environmental conditions is a central topic in evolutionary biology. In the present study, we investigated a wind-pollinated woody species of Changbai Mountain of northeastern China, namely, Betula ermanii Cham. This woody species B. ermanii is not only a dominant species in subalpine forest (SF), but it also occurs in the alpine tundra (AT) regions. This attribute indicates that it may play important roles in the two contrast habitats. In order to evaluate the influences of different habitats on differentiation in B. ermanii, we assessed the genetic and epigenetic population structure in selected populations from two contrasting habitats by using amplified fragment length polymorphism (AFLP) and methylation-sensitive AFLP techniques. According to our results, the AT group not only exhibits higher genetic and epigenetic diversity than the SF group but also shows greater population ...