Description
Fungi are key players in terrestrial ecosystems as decomposers, pathogens and symbionts, but little is known about fungal diversity in arctic habitats. Most fungi do not produce fruit-bodies and therefore recently evolved high-throughput DNA-based methods are required for identification. The project aims to database arctic fungi, uncover the key factors affecting fungal diversity and determine the fungal communities of relict arctic plants in temperate habitats. These results provide a prognosis of the gradual large-scale climate change on arctic plants and fungi with a perspective for developing conservation measures. The collaboration benefits from bioinformatics, molecular identification and databasing capacity of the Estonian partner and arctic ecological knowledge, taxonomic skills and experience with high-throughput sequencing methods of the Norwegian partners. Exchange of such complementary scientific skills will strongly benefit future scientific work of both partners and potentially results in a longer-term collaboration.
Summary of project results
Fungi are key players in terrestrial ecosystems as decomposers, pathogens and mutualists. In arctic habitats, ecto- and ericoid mycorrhizal and root endophytic symbiosis dominate due to adaptation to highly organic, nutrient-poor soils. However, little is known about the fungal diversity in arctic habitats. Since most fungi do not produce conspicuous fruit-bodies, DNA-based methods are required to uncover the fungal diversity. The recently developed high-throughput sequencing (HTS) techniques provide great potential for exploring the fungal diversity, but these methods have their shortcomings and inherent biases. The principal objectives were to 1) compare the relative performance of HTS tools; 2) develop strategies for standardisation and improved quantitative view; 3) develop a global fungal identifier by integrating high-quality sequence databases, clustering, alignment and phylogenetic tools. Within this project a massive reference data set from boreal and arctic fungi was generated that has been deposited in the UNITE database (
http://unite.ut.ee), with a link to GenBank and communicable as interactive digital object identifier-based taxonomic entities. In terms of bioinformatics and databasing a PlutoF workbench-associated tool for storing quality-filtered high-throughput sequencing data and metadata for easy access and rapid download was elaborated. In parallel with identification a novel method for the genome sequencing of fungi from old voucher specimens using minute quantities of initial material was developed. The results also showed that soil-inhabiting saprotrophic and ectomycorrhizal fungi exhibit strong seasonal patterns that are further complicated by annual variation, depending on soil moisture. In atypical growth habitats and microsites, the diversity of ectomycorrhizal fungi was lower compared to more typical microsites. Despite this, the distinct communities of atypical habitats contribute to the overall richness. This also alerts that with global change, the proportion of such edge habitats with depauperate fungal diversity may become more common. By definition, these edge habitats are more vulnerable to environmental stress and local extinction. Taken together, all scientific and mutual scientific exchange objectives of the project were successfully performed.
Summary of bilateral results
Project has clearly been beneficial for both partners; Norwegian partner involvement has been strong. Involvement of the Norwegian partner was highly fruitful because it enabled to integrate different skills and knowledge, resulting in a more rapid and successful publishing of primary research. Of particular note was the Estonian researchers switch to use the sequencing service of Oslo University that has high quality and rapid turnover time due to highly qualified personnel. For the collaboration, it has added an additional dimension of benefit through the shared supervision of doctoral students and further applied collaboration projects for European funds (BiodivERsA, regional funding schemes). Due to this project, a tight collaboration with the Norwegian partner both in terms of intellectual and practical sides of research will be continued.