Major ongoing projects
Species and geographic focus
Research on abiotic adaption (soil and climate) covers an array of species: native Danish wood plant species growing in forests and open landscape, native and exotic forest timber species, Christmas/greenery trees. In total we work with domestication of more than 30 species at different levels of intensity. On biotic adaptation (pests and pathogens), we have on-going quantitative genetic and genomic research on the interaction between host species and their pests and pathogens (between Fraxinus sp. and Hymenoscyphus fraxineus, Abies nordmanniana and various insects and pathogens, Picea sitchensis and green aphids, and Ulmus sp. and Dutch elm disease). We also study interactions between native and invasive species at the genetic level, presently looking at the genetic implications of introduced Cytisus scoparius invading open landscapes.Activities in South-East Asia and Africa.
On-gong research activities cover sub-Saharian species of large local socio-economic and ecological value, with main focus on trees in the West-african parklands and sahelian areas (including Adansonia digitata, Parkia biglobosa, Vitteralia paradoxa, Acacia senegal). On conservation of tropical trees species, we work with partners in South-East Asia and Africa on application of genetic markers and novel genomic tools to strengthen local efforts on conservation and sustainable use of endangered or vulnerable species including Dalbergia and Eusideroxylon zwageri.
The research group is a key partner in Danish activities on breeding programs of quality timber, landscape species and superior Christmas trees/greenery, but also holds substantial experience on domestication and conservation of tropical species. In relation to a transition towards bio-based economies, we intend to analyze and test if a wider use of species and planting material may integrate higher productivity with environmental and aesthetic values into landscape bioenergy plantings.
FADE - Fighting Ash Dieback with Endophytes
Funded by The Danish Council for Independent Research (DFF) DKK 3.469.536
Ash dieback caused by the fungus Chalara fraxinea was first recorded in Denmark in 2002, and it has thus far affected up to 90% of ashes in the country. Despite threatening European forestry for more than two decades, not much is known about the disease or an effective disease management. Recently, a small number of ash trees showing different degrees of resistance to the disease were found in populations of native Danish ash.
Although Danish experiments suggested that the resistance is likely to be genetically controlled, other extrinsic factors might as well contribute to the resistance. For example, endophytes – microbial endosymbionts that live within a plant without causing apparent disease – are long known to enhance disease resistance in trees. The presence of specific endophytes enhances resistance to Dutch elm disease in elm and to white pine blister rust in white pine.
Therefore, this project is established with three objectives: (I) to characterize an endophytic community associated with ashes resistant and susceptible to ash dieback in order to study interplay between endophytes, the hosts, and the pathogen (II) to isolate the endophytes and utilize them as a biological control agent (III) to understand defence mechanisms elicited by the endophytes. The knowledge gained from this project will be valuable for understanding the composition of endophytes and their involvement in resistance to ash dieback, but will also be important for management of the disease as well as conversation of ashes.
The Caspian forests of Iran: A gene pool for the adaptation of European forests?
Funded by Villum Fonden DKK 5.621.778
The project will test to which extend the Caspian forests in Iran contain genetic potential for our European forests and their ability to adapt to future challenges in terms of climate change, new diseases and pests. A more general aim is to contribute to the understanding of the evolutionary processes our forest tree species have undergone as a function of selection pressure (ice ages/human influence) and isolation (refugia conditions) and how these processes have influenced genetic diversity and adaptive potential of the tree species.
The project will collect seed from 6 selected tree species in the Caspian forests, each represented by up to 9 provenances. The seed will be used to establish provenance trials in afforestation areas in Denmark and Iran. The trials will also include European/Danish reference provenances. The provenance trials will be a unique infrastructure for the next decades for studies of forest tree adaptability and climate change. The test material will be subject to quantitative genetic analyses in additional fast-track single tree plot trials. All 6 species will be analyzed by DNA analyses to compare genetic diversity between the Caspian and Danish/European forests, as well as to describe the population genetic structure of the source populations.
Trees for the future forests
Funded by Villum Fonden DKK 5.900.000
This project addresses how to support high adaptive potential of trees that can grow well in the uncertain future climate. The long term health and fitness of our future forest trees are challenged by the predicted increasing temperatures, heavier and more frequent climate extremes (storms, droughts or floods), competition from new invasive species, and exposure to new pests and pathogens. On the other hand, global warming could also lead to increased productivity if the trees can utilize longer growing seasons. Based on the above background, the present project study how to select, improve (or prepare) the trees for the future forests?
We will use genetic and genomic approaches to study adaptive processes in trees. Time series observations from a large body of existing field trials will be combined with ecophysiological tests and front edge genomic techniques in the search for new understanding.
An important part of the project involves practical applicability of identified solutions. We will design genetic management solutions, predict their ecological and economic costs, risks and benefits. New trials will be established and guidelines for breeding of major tree species developed. Results from the project will help guide important decision on: Forestry practise that support on-going adaptation, Breeding for trees with high climate resilience and adaptability and Development of trees with high innate robustness against pest and pathogens.
Unravelling ash-dieback resistance: insights from single-cell analysis of tolerant and susceptible ashes across evolutionary divergent clades
Funded by The Danish Council for Independent Research (DFF) DKK 5.136.470
The invasive ash dieback pathogen, Hymenoscyphus fraxineus, causes severe damage on European ash. Our previous research has documented significant differences in susceptibility among clones of Fraxinus excelsior, but also among Fraxinus species of different evolutionary clades. In this project we hypothesize that phylogenetically related ash species with resistance against H. fraxineus share cellular defence responses that protect them against this pathogen.
The project aims are to explore the infection process of H. fraxineus, and compare cytological and molecular mechanisms among both resistant and susceptible species of Fraxinus and F. excelsior clones. The findings will reveal factors responsible for host resistance with the ultimate aim to strengthen future ash breeding. This is accomplished by i) in vivo comparison of cytological responses to infection by fluorescent-tagged H. fraxineus strains ii) identification of molecular defence mechanisms/pathways that moderate resistance to the fungus using single-cell transcriptomic analysis, and iii) comparison of cell wall composition using analytical chemistry. The results will increase the likelihood of identifying markers for breeding.