The wild service tree population in Bohemia is genetically distinct from that in Moravia
Species within the genus Sorbus are generally considered marginal and economically less significant in forestry, resulting in limited attention in both practice and research. Among the various Sorbus species, the wild service tree (Sorbus torminalis) is the most significant from a forestry standpoint, categorized as a rare forest tree species. It comprises more than one percent of the forest stands, covering approximately 4,350 hectares. There are also stands where this species represents less than one percent, totalling around 26,924 hectares. It is estimated that there are about 220,000 wild service tree individuals growing throughout the Czech Republic.
Photo: Flowering wild service tree in spring, archive of the VÚLHM
The wild service tree is found only sporadically in forest communities and does not form pure stands. It has limited competitive ability, and its fruits are a favourite food for wildlife. This tree thrives optimally in oak forests, specifically in warmer locations. It is a slow-growing species, typically reaching heights of 20 to 25 meters over the course of 80 to 100 years. In recent years, there has been a growing interest in cultivating the wild service tree, particularly for its highly valuable wood and for its potential to enhance stability and biodiversity in forest ecosystems. Additionally, its tolerance to drought makes it particularly promising in the context of ongoing climate change. Despite this, there is still a lack of comprehensive information regarding the species.
The development of natural populations of the wild service tree is closely linked to the genetic diversity of the individuals within those populations. Genetic diversity is a crucial aspect of overall biodiversity, yet it remains one of the least understood. Recent studies underscore the vital role that genetic diversity plays in the survival of viable populations across many species.
Scientists from the VÚLHM, v. v. i., Department of Forest Tree Species Biology and Breeding are conducting research on the wild service tree. Their work includes inventorying and mapping this species’ occurrences, as well as studying the genetic differentiation among individual wild service tree populations in the Czech Republic. As part of the research project NAZV No. QK23020020, titled “Utilization of DNA Analyses for Preserving the Desired Genetic Diversity of Recognized Sources of Qualified Reproductive Material and for the Genetic Characterization of Populations of Less Common Autochthonous Forest Tree Species” („Využití analýz DNA pro účely zachování žádoucí genetické diverzity uznaných zdrojů kvalifikovaného reprodukčního materiálu a pro genetickou charakterizaci populací méně běžných autochtonních druhů lesních dřevin“), they are collaborating with Mendel University in Brno. This project has resulted in several professional outputs. One notable achievement is the development of a certified methodology that describes DNA analysis procedures using polymorphic microsatellite markers. These methods enable the monitoring of genetic diversity and the identification of clonal identity in the wild service tree – a species often overlooked but crucial for enhancing biodiversity in forest ecosystems. Additionally, verifying the identity of clones in seed orchards or clone mixtures, as well as monitoring genetic diversity, will help improve the quality of reproductive resources.
Photo: Wild service tree in autumn in the Bohemian Central Highlands, archive of the VÚLHM
A comprehensive description of the methodological procedures for DNA analyses using microsatellite markers to verify genetic characteristics of the wild service tree has not yet been published for the Czech Republic.
To monitor genetic diversity among stands of the wild service tree and to identify individuals with the same genotype (clones), a set of SSR markers was selected and tested on 320 individuals from 14 locations throughout the Czech Republic.
The analysis revealed significant differences in the structures of the wild service tree populations between the Czech and Moravian regions. In contrast, geographically close populations, such as those from the Bohemian Central Highlands, Moravia, and Central Bohemia, showed similar structures.
The published methodological procedures for DNA analyses are effective not only for identifying clones of reproductive material but can also help distinguish the genetic structures among wild service tree individuals from different geographical locations.
These clonal identification procedures can be utilised in user control mechanisms, such as in seed orchards, which are among the most effective strategies for conserving the genetic resources of forest tree species. However, in the Czech Republic, there are currently only four certified seed orchards registered for the wild service tree.
The legislation of the European Union mandates that Member States implement a functional control system for the reproductive material of forest trees. In the Czech Republic, this control system has traditionally relied on monitoring registration records. To objectively verify the claimed clonal identity of sources of forest tree reproductive material, such as seed orchards, clone archives, and clone mixtures, DNA analyses utilising microsatellite markers can be employed. These markers are effective for identifying individual trees.
Photo: Wild service tree – leaves and fruits in autumn, archive of the VÚLHM
Genetic diversity verification procedures form the foundation for a targeted increase in genetic variability among forest stands. This increased variability enhances the stability and resilience of these stands against potential diseases, pests, and adverse climate conditions. Incorporating a greater number of tree species in forestry, particularly by increasing the presence of rare broadleaved trees, is crucial for safeguarding forest stability against risks such as pest outbreaks, pathogens, forest fires, and habitat loss.
In response to ongoing climate change, forest owners are actively seeking ways to enhance the resilience of their stands. They aim to establish mixed forests to reduce the risks and damage associated with unpredictable events. Consequently, the wild service tree has gained increased attention from forest owners in Central Europe due to its valuable wood and high tolerance to drought and pathogens.
Understanding the genetic diversity of tree populations is also essential for achieving the goals outlined in the State Environmental Policy of the Czech Republic, the Strategy for the Protection of Biodiversity of the Czech Republic 2026–2050, and the country’s international commitments to biodiversity protection.
The reproduction of gene-rich populations ensures the development of more stable and resilient stands, which can enhance biodiversity and better adapt to potential climate changes, ultimately contributing to environmental protection.
The certified methodology titled “Methodological Procedures for Verifying Clonal Identity and Characterizing Genetic Diversity in the Wild Service Tree Using Microsatellite Markers” („Metodické postupy ověřování klonové identity a charakterizace genetické diverzity u jeřábu břeku s využitím mikrosatelitových markerů“) is available for download here.
Authors: Ing. Pavlína Máchová, Ph.D., Ing. Helena Cvrčková, Ph.D., Mgr. Martina Komárková, Ph.D., Ing. Olga Trčková, Bc. Kateřina Vítová, VÚLHM, v. v. i., Strnady, e-mail: machova@vulhm.cz; doc. Ing. Pavel Hanáček, Ph.D., Mendelova univerzita v Brně
According original, prepared by Jan Řezáč, e-mail: rezac@vulhm.cz