THE GEOGRAPHICAL-DISTRIBUTION OF GENETIC-VARIATION OF SILVER FIR (ABIES-ALBA, PINACEAE) IN RELATION TO ITS MIGRATION HISTORY

Silver fir presently occurs in many mountainous regions of eastern, we stern, southern and Central Europe. In order to elucidate the biogeogr aphic history of fir populations in different European areas, the dist ribution of area-specific alleles at eight enzyme loci and the allele frequency distributions at seven polymorphic enzyme loci were investig ated in seed or bud samples from 48 provenances comprising 98 single s tands. Due to great genetic divergence among different populations loc ated near the ancient glacial retreats, it was concluded that silver f ir survived in five refugia during the last glaciation but migrated fr om only three refugia to its present natural range. The occurrence of unique alleles in particular fir areas indicated its migratory routes to the north and the existence of a few introgression zones where silv er fir from different refugia has met during its expansion.