Genetic diversity in European beech (Fagus sylvatica L.) seed stands in the Romanian Carpathians

In Romania, European beech (Fagus sylvatica L.) is the most important broadleaved tree species. The goal of the present study was to determine the genetic diversity and differentiation in and between natural beech populations from the Romanian Carpathians and the transmission of the genetic diversity to the next generation. The populations analyzed were registered as seed stands. Genetic analysis was based on ten nuclear microsatellites. The highest amount of genetic variation was within populations, whereas genetic differentiation between populations was low. In the adult populations the mean number of alleles per locus varied from 8.0 to 10.9, the effective number from 8.3 to 9.6. Heterozygosity ranged from 0.637 to 0.750 with the mean of 0.681(±0.018). The overall genetic differentiation FST between populations averaged 0.014. Geographic patterns within this region were not detected. Regenerating these stands naturally has not implied a reduction in the genetic variation in the following generation. Allelic richness, genetic diversity and heterozygosity in adult stands and their natural regeneration is not significantly different. Inbreeding effects were not observed (F between -0.032 and 0.061). The results complete the knowledge on genetic variation of beech in Romania and give insides into the genetic diversity of beech seed stands. They can be helpful too for the delineation of provenance regions in the Romanian Carpathians.