Plant morphological variability at the distribution edges: the case of Dryas octopetala (Rosaceae) in northern Greece

Abstract

Plant populations at their distribution limits may often deviate morphologically from those at the centre of their range (core populations). A similar pattern was observed in Dryas octopetala (Rosaceae), a circumpolar, arctic-alpine species distributed in northern and central Europe, reaching south to northern Greece. The three southernmost populations of Europe, located in Greece, were sampled and specific leaf morphometric traits were measured and analysed using canonical variates analysis (CVA) and hierarchical cluster analysis. CVA revealed that the three samples of D. octopetala did not form one group but were significantly discriminated. Despite the rather similar climatic conditions of Mts Falakron and Orvilos, the sample of Mt Falakron was grouped with that of Mt Tzena, based on leaf morphology. These findings contradict findings from other studies on the ways with which plants react and adapt on areas of harsh climatic conditions. Micro-site conditions or a potentially different post-glacial origin could possibly explain the pattern observed in this study.