EN
Individual trees growing in five populations of European beech (Fagus sylvatica L.) in the Sudety Mountains were investigated in respect of variability of peroxidases (2 loci) and malate dehydrogenase (1 locus). Differences between populations were illustrated by a dendrogram constructed on the basis of Hedrick's (1974) genetic distances. The mean GST coefficient (=0.0333) value demonstrated the higher level of intra-population variability, as compared to the inter-population (DST = 0.0149) variability.