Decline of oak forests due to agricultural activities and environmental pollution during last decades has arisen again the interest in taxonomy of oaks in Slovenia. There are several unresolved taxonomic problems connected to oaks species. Especially taxons under species level are poorly known due to great polymorphism of ecotypes and provenance, and existence of interspecific hybrids almost between all species. The results of taxonomic study of pedunculate oak (Quercus robur L.) are presented on the poster.
A taxonomic study was carried out in seven pedunculate oak populations from Slovenia by leaf morphometry and DNA analysis. About 100 leaves were sampled from five trees from seminatural peduculate oak stands, distributed throughout the Slovenia. Samples were collected from the well lit upper part of the tree crowns, and only leaves from short twigs were analysed. Leaves were herbalised, and measured and assessed in the laboratory. When present, acorns were also collected. Leaf dimension (lamina length and width, petiole length, number of lobe pairs) were measured and characters like type of leaf pubescence and leaf lamina base type were assessed. Acorn diameter and length were measured and cupola scale type and pubescence were observed. RAPD markers were used for genomic DNA analysis.
First results of leaf morphometry showed that almost all sampled trees belong to the Quercus robur L. species. Nevertheless, on some trees, leaves showed also characters typical for the sessile oak (Quercus petraea/Matt./Leibl.), especially the leaf lamina base type, type of pubescence and number of leaf lobe pairs. The hybrid status of morphologically untypical trees was not always confirmed by DNA analysis. The estimated genetic diversity of the three already analysed populations was between 0.275 and 0.316. Probably, some other DNA markers would be necessary in order to help resolving taxonomic problems of oaks on DNA level.
Key words: Quercus robur L. , taxonomy, leaf morphology, multivariate analysis, genetic molecular markers, RAPD, interspecific hybrids.
Correspondence: Franc Batic, Agronomy Department, Biotechnical Faculty, University of Ljubljana, Jamnikarjeva 101, SLO-61000 Ljubljana, Slovenia
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