Periodic Reporting for period 3 - GenTree (Optimising the management and sustainable use of forest genetic resources in Europe)
Reporting period: 2019-03-01 to 2020-02-29
For years, the European Union (EU) has been successfully promoting forest genetic diversity as a resource to conserve and a way to protect forests and their biodiversity in Europe better. At the same time, it has successfully promoted breeding as a way to increase the sustainability and the strength of the European forest economic sector. Until now, those two success stories rarely crossed paths. As a result, both conservation and breeding have focused on a limited amount of species that are no longer diversified enough in an era of changing societal demands and increased environmental uncertainty.
Why is it important for society?
EU forests and other wooded land account for ca. 180 million hectares (42.4% of EU land area). Europeans derive many supporting, provisioning, regulating and cultural ecosystem services from their forests. The economic weight of the EU-28 wood-based forestry sector generated a gross benefit representing 7.5% of the manufacturing total in 2016. In addition, wood-based industries employed 3.1 million persons across the EU-27 in 2018, a significant 10.5% share of the manufacturing total. At the UN Paris Climate Conference in 2015, forests were recognized as essential for the mitigation of climate warming. Society has an obvious interest in sustainably managing forests now more than ever.
European forests are made of a relatively low number of economically valuable, genetically rich and mostly native tree species. These large and diverse genetic resources are a key component of forest adaptation to climate change. The future of native European forests depends greatly on the management and sustainable use of their genetic resources.
What were the overall objectives of GenTree?
The goal of GenTree was to provide the European forestry sector with better knowledge, methods and tools for management and sustainable use of forest genetic resources (FGR) in Europe. To reach its goal, GenTree made scientific, technological and implementation breakthroughs in:
- The design of innovative strategies for conserving FGR in European forests;
- Broadening the range of FGR used in European breeding programmes;
- The integration of conservation and breeding strategies to provide a new framework for the development of adaptive forest management.
GenTree focused on the twelve most economically, ecologically and socially important forest tree species in Europe.
The project concluded with a series of international events held in Avignon, France, in January 2020 that highlighted the impressive scientific, technical and dissemination work carried out by the GenTree consortium since 2016. The large, carbon-neutral scientific conference organized by GenTree during this week (#rescueforest) was entirely filmed and the talks are available on-line via the project website.
In total, 4700+ trees from 12 species and 210 sites were sampled across Europe. Trees in populations were characterized for traits useful for adaptation and response to global change, from both a conservation and a breeding perspective, and their leaves sampled for DNA extraction and functional trait measurements. The ecological and climate conditions of the sites were fully described.
The DNA sequencing strategies used in GenTree target gene families and functions that are relevant for adaptation and similarly expressed in all species, both facilitating sequencing and making comparisons across species relevant when looking for the demographic and selection processes involved in how diversity is expressed within and among populations, at local, landscape and regional levels.
An important but rarely done assessment in forest trees, is to look for signatures of selection at the early stage of life, that of germination. After an extensive assessment of seed yield across Europe, surveying all species of the project, Pinus sylvestris, Betula pendula and Pinus pinaster were chosen for the in-situ germination experiment. Results showed a large phenotypic variability in root emergence time and stem development time across distribution ranges, and suggested an early adaptive response to the environment.
Traits and genetic combinations important for breeding under climate change constraints were found in marginal and peripheral populations, themselves less resilient than core populations, making them urgent targets for both conservation and breeding. High-throughput methods such as unmanned and infrared spectrum devices, as well as leaf chemistry and genomics were all found relevant in-situ. Currently used Forest Reproductive Material in Europe showed an overall, albeit truncated, similarity with wild material that should be compensated by creating ex-situ core collections.
Modelling took up a large part of the activities of GenTree. It was used to upgrade and implement innovative, low-cost breeding strategies, designed to balance genetic gain with loss of genetic diversity. Modelling also demonstrated that genetic variability reduces the risk of population extinction under current and future climatic conditions, particularly at the warm, southern margins of species distribution ranges. Thinning and assisted migration had significant but low positive effect in mitigating vulnerability.
Stakeholders’ engagement also took up a significant part of the project’s activity. Stakeholders surveyed by GenTree were aware of the importance of genetic diversity for forestry. However, their perception of which policy or legislation is helpful or detrimental to FGR, varied widely, chiefly by country. To raise awareness further on how genetic diversity can be a nature-based solution for adapting forests and forestry, GenTree organized several events targeting policy-makers, forest managers and administration executives, often in collaboration with the EUFORGEN programme."
The 12 forest tree species studied by the GenTree consortium can be considered as models for all forest tree species listed in Directive 1999/105/EC, which regulates their trade in the EU. This is because these 12 species cover a wide range of bioclimates and forestry use, but also because the scientific analysis approaches used in GenTree relied strongly on integrated sampling strategies, transferable genomic methods and process-based modelling. When fully exploited, the data provided by GenTree (open access and re-usable) will have considerably increased our understanding of the where and how of local adaptation.
Other long-term expected impacts include providing evidence of the role of policy change concerning FGR on the forest nursery sector, demonstrating the role of FGR conservation in managing protected areas, contributing to nature-based solutions and helping sustainably manage forests at a time when environmental conditions are drastically changing.