Description
Main challenge of the project is to reduce the risks in economy and natural biodiversity through the DNA-based early diagnostic methods of forest and plant pathology. Once an introduced species has established in an area, it is very difficult to eliminate. Therefore measures to prevent the introduction of invasive pathogens are crucial for successful control as rapid detection of pathogen presence enables us to elaborate operative and timely control and disinfection treatments. The obtained results will be discussed with the forest managers and national authorities controlling import of tree material in order to elucidate practical applications. The elucidation of the introductory pathways of the targeted two invasive pathogens will increase political and public awareness of the risks involved in plant trading. Sequencing and bioinformatics part of the project takes place in the Norwegian Forest and Landscape Institute. The collaboration with experts in molecular biology and bioinformatics in Norway will expose Estonian to new and ground-breaking technologies being used for metagenomic studies and for population and evolutionary studies.
Summary of project results
During the last ten years the Baltic and Nordic forests have become increasingly challenged by new pathogens. This process has apparently been triggered by climate change and intercontinental trade of biological material. The annual economic costs due to invasive alien species within Europe alone have been estimated as 12 billion euros. Once an introduced species has become established in a new area, it is very difficult to eliminate it. Therefore one project objective was to design and implement DNA-based diagnostic methods that allow early detection pathogens. By employing these protocols, altogether 113 imported seedling, seed and wood samples were analysed. A new pathogen was found in 6 samples. For the first time in the world, the invasive pine needle pathogen Dothistroma septosporum was found on seedlings of Picea omorika. This finding demonstrates the extended risks of plant trade, i.e. pathogens may also be imported together with previously unknown hosts. A second project objective was to analyse the pathways of spreading of new pathogens. In the population genetic analysis was found no support to the hypothesis that the targeted pathogens in north Europe (the agent of ash dieback, Hymenoscyphus fraxineus; red band needle blight pathogen, D. septosporum) could originate directly from Far East Asia, a region of extensive plant import to Europe. In contrast, D. septosporum showed gene flow of opposite direction, i.e. from northern Europe to Far East Asia. The population data showed that H. fraxineus in Europe is not originated from Far East Asia, which is in contrast to the former knowledge. Additional results include discovery of 1) new locations for the quarantine pine needle pathogen, Lecanosticta acicola, and 2) new host species for the ash dieback pathogen H. fraxineus and the pine pathogen Diplodia sapinea. The project demonstrates the risks involved in international plant trade. Increased political and public awareness is needed to meet this threat.
Summary of bilateral results
Project promoter have had an excellent cooperation with the Norwegian colleagues in several points as planning and design of sampling work, planning of expedition to the Russian Far East, sample preparation for molecular work, and supporting the scientific paper writing process. Cooperation is reflected in somel co-authored papers. Cooperation work benefited from the state-of-the-art methods established in the molecular biology lab at the Norwegian partner. The visit to the Norwegian lab in 2015 was devoted to the Estonian team learning RAD tag analysis by Ion Torrent PGM and preparing jointly all the H. fraxineus DNA samples to population genetics study by RAD tag analysis. PhD student Ahto Agan has been supervised by the Norwegian team when adopting real-time PCR technology at the lab of the Estonian partner for pathogen quantification in host tissues. The project ideas were presented the in the COST meetings. All this has strengthened the international collaboration with forest pathologists.