1. Genetic diversity of beech in Greece
A.C. Papageorgiou (1)
, I. Tsiripidis (2)
, S. Hatziskakis (1)
Democritus University of Thrace
(1)
Forest Genetics Laboratory
Orestiada, Greece
(2)
Aristotle University of Thessaloniki
Biology Faculty, Laboratory of Plant Systematics and Plant Geography

2. Outline
• Presentation of diversity studies about
beech in Greece
– cpDNA SSR markers
– Leaf morphology
• Detailed diversity patterns in two areas
– Southern Rodopi
– Paggeo

3. Beech distribution in Greece
Moulopoulos, 1965
Tsiripidis, 2001

4. Beech in Greece
• Mountainous “island” populations
• Broad range of ecological conditions
• One species, with two interfertile
subspecies
– Fagus sylvatica var. sylvatica
– Fagus sylvatica var. orientalis
• At least two glacial refugia (pollen data)

5. Pollen data
Huntley & Birks 1983

6. Genetic diversity of beech in Europe
• High nuclear DNA diversity within
populations
• Low cpDNA diversity and differentiation
• Diversity higher in the Balkans
• More cpDNA haplotypes in Italy and the
Balkans

7. Latest theory about beech origin
• European beech derives mainly from
migration out of refugia in Istria and S.
France
• Italian lineages were blocked
• Balkan lineages did not expand much after
the last glaciation period
• Beech did not migrate from the Balkans to
the north
– The opposite is rather assumed

8. SSR cpDNA haplotypes

9. cpDNA haplotypes in Greece
• 40 populations sampled covering the
whole geographical range
– 38 in Greece
– 2 in East Thrace (Turkey)
• 5 trees / population
• 3 polymorphic SSR primers
• 13 haplotypes

10. Hatziskakis et al. 2009

11. Beech cpDNA patterns in Greece
• High overall variation
• Very high differentiation among populations
– Low spatial geographic structure
• Explanation
– At least 3 refugial areas
• Pindos, Rodopi, Paggeo
– Distant and close-by lineages
• North and Rodopi haplotypes migration
– Introgression between two subspecies
• “orientalis” influence in eastern and central Greece

12. TCS haplotype network
• Mutational steps
• Western and northern
haplotypes group
together
• Eastern haplotypes
have common origin
with the Rodopi ones
• Possible common
origin during past
glacial periods

13. Leaf morphology
• Same 40 populations
• 25 trees / population and 20 leaves / tree
• Leaves scanned and stored digitally
• More than 30 characters measured
– Systematically important
• Multivariate statistics
– PCA
– Clustering
– Grouping defined by genetic results

14. Results
• High diversity
• Four PCA axes
– First two PCA axes explain 80% of variation
• Size and shape
– Next two only 10%
• Petiole and leaf perimeter
• Leaf morphology follows geographical and
environmental parameters
• Lineages defined by cpDNA haplotypes also
show some influence

15. Beech in Rodopi
• Morphology changes from east to west
– Indicating an introgression zone
• Genetic diversity increases in the eastern part of the
mountain
– In cpDNA (SSR) and genomic DNA (AFLPs)
• Eastern haplotypes located in eastern part of the
mountain
• Eastern lineage occupies lower altitudes, while a western
lineage occupies higher altitudes
– Adaptation (?)
– Migration history
– Both in gene markers and morphology

16. Gene diversity in Rodopi

17. Beech in Paggeo mt.
• NE Greece
• Isolated massif
• Near a refugial area
• Beech coverage over different altitudes
(600 – 1700m)
• Different beech ecotypes
– Described by plant communities

18. Paggeo mt.

19. Beech diversity in Paggeo
• Eastern cpDNA haplotypes cover the higher
altitudes while western haplotypes the lower
ones
– The opposite trend than Rodopi
• Leaf morphology indicated the opposite
– Environmentally influenced in small scale
• Complex post glacial movement in time and
space resulted in this pattern
– Eastern haplotypes climbed the north slope to the top
– Local refugial haplotype remained in the central part
of the mountain
– Western haplotypes remained in low elevations

21. In conclusion
• Beech in Greece has a complex diversity pattern
deriving from different lineages from close-by or
distant refugia
• Introgression of the two subspecies is evident,
especially in the north-east
• Morphological traits follow both environmental
and genetic grouping
• Mountains contain complex structures in a small
scale, indicating complex migration events

23. Thank you for your attention