Fagus sylvatica - EUFORGEN European forest genetic resources programme

Genetic summary

Genetic diversity and variation

European beech has high genetic diversity with significant diversity between populations (von Wuehlisch, 2008). However, up to 95 per cent of genetic variability is within populations, which is typical for long-lived wind-pollinated tree species. Continuous forests in pure or mixed stands dominated by beech may have less genetic diversity than fragmented stands in more mixed forests (Rajendra et al., 2014). Therefore, countries with many isolated populations (such as Italy) may have higher genetic diversity and differentiation than those with fewer but larger populations.

High genetic variation offers resilience against pests and diseases and a high potential to adapt to changing environmental conditions and different ecological niches, ensuring survival and adaptation in diverse ecosystems. Even on the leading edge of European beech’s distribution the species is still able to adapt to better suit the changing environmental conditions even in small populations. For example, in the northeastern range of the species some populations have high frost tolerance as a genetic trait (Kramer et al., 2010). Despite future changes brought on by climate change, genetic diversity of European beech is expected to remain stable or even increase within the centre of its distribution (Kramer et al., 2010).

Genetic distribution and clustering

There is significant genetic differentiation among populations due to glaciation, isolation, intensive management, forest degradation, and local adaptation leading to altered genetic variation patterns (Rajendra et al., 2014). Within Europe, northern populations of beech have lower genetic variability than southern populations, possibly because of the short time they have had to differentiate since the last glaciation, glacial refugia being more common in the south, and a greater variety of ecological conditions for beech to grow in the south (Leonardi and Menozzi, 1995).

In Europe, genetic differentiation within populations of beech is higher in Mediterranean populations, while areas such as Bavaria show low levels of genetic variation. In Italy, northern and southern populations are clearly genetically differentiated, with southern populations possessing higher genetic diversity, as might be expected from areas such as Sicily that may have been glacial refugia (Leonardi and Menozzi, 1995). Genetic studies have identified distinct genetic clusters and unique variations in different regions.

Trees within 30 m of each other are more genetically like each other than would be expected from random distribution of genotypes; this is the result of the limited distance of seed dispersal (Vornam, Decarli, and Gailing, 2004). In dense stands, the migration distance of pollen and seeds may be limited to 50 m, one reason being because the heavy fruits of beech limit seed dispersal.

The bibliographic review was conducted by James Chaplin of the EUFORGEN Secretariat in August 2024.

Further relevant genetic traits

Cultivation and human intervention

Despite being managed for centuries, European beech genetic diversity has not been greatly affected by forestry practices due to the dominance of natural regeneration (Rajendra et al., 2014). The genetic diversity in managed stands is comparable to that of natural stands, although spatial structure is less in managed stands and some rare alleles may be lost (Rajendra et al., 2014). However, artificial stands are often clearly differentiated genetically from native stands, originating from different provenances.

Glacial biogeography evolution

Many European populations of beech have common origins from a few glacial refugial populations, although northern Europe may have been recolonized from a single refugial population in the southeast of the continent (Papageorgiou et al., 2007; Rajendra et al., 2014). Genetic studies reveal glacial refugia in the Balkans, southern France, Greece, the Iberian Peninsula, Istria, and Italy, but most European beech originates from populations in southern France and Istria (Papageorgiou et al., 2007). Beech trees in Germany may have originated from one refuge in Slovenia or the eastern alps according to genetic analysis (Rajendra et al., 2014).

The bibliographic review was conducted by James Chaplin of the EUFORGEN Secretariat in August 2024.

Genetic conservation

Fragmentation of forests and changing land-uses can lead to genetic drift, disrupting gene flow and altering mating patters, and affecting the genetic structure of beech forests in Europe (Rajendra et al., 2014). This is especially the case for beech, which prefers land that is good for agriculture and thus is often cleared; this has resulted in a large proportion of beech genetic diversity being lost and populations fragmented (von Wuehlisch, 2008). Fragmented and marginal populations of beech have less allelic richness and greater instances of inbreeding but still the same genetic diversity as more central populations (Rajendra et al., 2014).

Both in situ and ex situ approaches should be used for optimal conservation of the species, with seed collection from years with abundant production. Enough seed should be collected to ensure the widest range of genetic diversity is sampled. Seeds should be collected over large areas to prevent a bias of a few families (von Wuehlisch, 2008). Ex situ methods includes gene reserve forests that should be at least 100 ha to efficiently contain sufficient genetic variability, but seeds collected from smaller fragment populations can be held in smaller forests (von Wuehlisch, 2008).

The bibliographic review was conducted by James Chaplin of the EUFORGEN Secretariat in August 2024.

Fagus sylvatica
European beech

Environmental zones

Status of Fagus sylvatica conservation in Europe

Genetic summary

Genetic diversity and variation

Genetic distribution and clustering

Further relevant genetic traits

Cultivation and human intervention

Glacial biogeography evolution

Genetic conservation

Genetic Characterisation of Fagus sylvatica and its GCUs

Availability of FRM

EUFORGEN’s publications

Technical guidelines for genetic conservation and use

Fagus sylvatica - Technical guidelines for genetic conservation and use for European beech

Related publications

Social Broadleaves Network: Report of the fourth meeting

Stand-forming Broadleaves Network: Summary of the first meeting

Stand-forming Broadleaves Network: Summary of the second meeting

Social Broadleaves Network: Report of the third meeting

Social Broadleaves Network: Report of the second meeting

Social Broadleaves Network: Report of the fifth meeting (Temperate Oaks and Beech network)

Social Broadleaves Network: Report of the first meeting

Forest Management Network: Summary of the second meeting

Contacts of experts

Further reading

References

Fagus sylvaticaEuropean beech

Environmental zones

Status of Fagus sylvatica conservation in Europe

Genetic summary

Genetic diversity and variation

Genetic distribution and clustering

Further relevant genetic traits

Cultivation and human intervention

Glacial biogeography evolution

Genetic conservation

Genetic Characterisation of Fagus sylvatica and its GCUs

Availability of FRM

EUFORGEN’s publications

Technical guidelines for genetic conservation and use

Fagus sylvatica - Technical guidelines for genetic conservation and use for European beech

Related publications

Social Broadleaves Network: Report of the fourth meeting

Stand-forming Broadleaves Network: Summary of the first meeting

Stand-forming Broadleaves Network: Summary of the second meeting

Social Broadleaves Network: Report of the third meeting

Social Broadleaves Network: Report of the second meeting

Social Broadleaves Network: Report of the fifth meeting (Temperate Oaks and Beech network)

Social Broadleaves Network: Report of the first meeting

Forest Management Network: Summary of the second meeting

Contacts of experts

Further reading

References

Fagus sylvatica
European beech