ZLV Online

Abstract

Investigation of variability within Betula genus in the Giant Mountains (Krkonoše) was made on the basis of selected morphological traits/features measured on leaves. The aim of this work was to assess a discrimination power of these traits. Another objective was to determine which of these traits are the most influenced by environmental conditions. Altogether, 73 individuals on 4 locations were evaluated. For each tree the genome size and ploidy levels were determined by a method of flow cytometry. Our sample contained tetraploids and diploids. Evaluation used both traditional/classical and geometric morphometrics. Traditional morphometrics used 22 primary traits and 8 proportional traits. Differentiation between diploids and tetraploids was noticeable; 14 traits showed statistical significance. When comparing tetraploid birches from 4 sites of interest, 12 measured traits yielded statistically significant difference. The most differentiated population in terms of both traditional and geometric morphometrics was found in the Obří důl valley. However, this difference cannot be interpreted in taxonomy without application of molecular genetics and further studies within a wider region. Humidity of selected stands did not influence the morphology of sampled individuals; only one single trait was close to α = 0.05.