The Random Amplified Polymorphic DNA (RAPD) technique was used to assess the genetic polymorphism of Fraxinus excelsior L. in three families (K-59, T-3, and N-5) obtained by mature embryo culture in vitro. Analysis of 15 offspring showed polymorphic DNA bands with 12 oligonucleotide primers. A total of 139 RAPD bands were scored, of which 92% were polymorphic. These results confirm that the studied offspring exhibited high genetic variation between three families of common ash. We have revealed nine primers, each of which, when used separately can identify all studied genotypes.

The simple sequence repeat (microsatellites) method was established together with the necessary basic laboratory techniques as developed by an Austrian lab. An assessment of genetic diversity of selected Fraxinus excelsior trees and their offspring from Lithuania served as the case study. Results demonstrated that in contrast to RAPD, many more alleles at each locus were present, and some offspring of individual trees grouped together after clustering.

Key words: Fraxinus excelsior, microsatellites, RAPD, offspring, maternal tree, genetic diversity