Articles containing the keyword 'Diplodia tip blight'

With ongoing climate change, the risk caused by both native, well-known pathogens and new, invasive ones is increasing. Diplodia sapinea (Fr.) Fuckel is responsible for Diplodia tip blight, a new fungal disease in Finland, that kills the current-year shoots of Scots pine (Pinus sylvestris L.). This can lead to the death of young trees and increase the susceptibility of trees of all ages to other stressors. Since D. sapinea spreads by airborne spores, it cannot be eradicated. In this study, we present the first screening to evaluate the potential for harnessing the genetic variation of Scots pine to improve its resilience against D. sapinea. Further, we wanted to test if predisposing this warm-preferring pathogen to higher temperature will increase its virulence. On the contrary, higher temperature initially reduced the virulence of D. sapinea, but the effect diminished over time. Based on necrosis length, we observed between-family variation in seedling resistance. These findings support the need for larger future trials to explore the potential for harnessing genetic variation to enhance resistance against D. sapinea.

• Terhonen, Natural Resources Institute Finland (Luke), Forest health and biodiversity, Latokartanonkaari 9, 00790 Helsinki, Finland https://orcid.org/0000-0002-9288-440X E-mail: eeva.terhonen@luke.fi
• Kujala, Natural Resources Institute Finland (Luke), Forest tree breeding, Paavo Havaksen tie 3, 90570 Oulu, Finland https://orcid.org/0000-0003-0949-6156 E-mail: sonja.kujala@luke.fi
• Pyhäjärvi, University of Helsinki, Faculty of Agriculture and Forestry, Department of Forest Sciences, Viikki Plant Science Centre, Latokartanonkaari 7, 00014 University of Helsinki, Finland https://orcid.org/0000-0001-6958-5172 E-mail: tanja.pyhajarvi@helsinki.fi
• Sutela, Natural Resources Institute Finland (Luke), Forest health and biodiversity, Latokartanonkaari 9, 00790 Helsinki, Finland E-mail: suvi.sutela@luke.fi

The aim of this study was to determine if the ascomycete fungus Sphaeropsis sapinea (Fr.) Dyko & B. Sutton (syn. Diplodia sapinea (Fr.) Fuckel) could be cultured from surface sterilized Scots pine twigs presenting the endophytic stage of this fungus. This fungus causes the disease called Diplodia tip blight in conifers. Symptoms become visible when trees have been weakened by abiotic stressors related to temperature, drought and hailstorms. The disease is rapidly increasing and is observed regularly in Scots pine (Pinus sylvestris L.) forests in Europe. Changes in climatic conditions will gradually increase the damage of this pathogen, because it is favored by elevated temperatures and additionally the host trees will be more susceptible due to related environmental stress. Diplodia tip blight is emerging towards Northern latitudes, thus, actions to monitor the spread of S. sapinea in pine-dominated forests should be undertaken in Finland. Our aim was to search for S. sapinea in Scots pine along a transect in Finland. Branch samples were collected from healthy Scots pine, fungal endophytes were isolated and morphologically identified. Sixteen S. sapinea strains were found from four Scots pine trees from two locations. This finding confirms that S. sapinea is found as an endophyte in healthy Scots pine in Finland.

• Terhonen, Forest Pathology Research Group, Department of Forest Botany and Tree Physiology, Faculty of Forest Sciences and Forest Ecology, University of Goettingen, Büsgen-Institute, Büsgenweg 2, D-37077 Göttingen, Germany E-mail: terhonen@uni-goettingen.de
• Babalola, Forest Pathology Research Group, Department of Forest Botany and Tree Physiology, Faculty of Forest Sciences and Forest Ecology, University of Goettingen, Büsgen-Institute, Büsgenweg 2, D-37077 Göttingen, Germany E-mail: j.babalola@stud.uni-goettingen.de
• Kasanen, Forest Pathology Lab, Department of Forest Sciences, University of Helsinki, Latokartanonkaari 7, FI-00014 University of Helsinki, Finland E-mail: risto.kasanen@helsinki.fi
• Jalkanen, Rovaniemi Research Unit, Natural Resources Institute Finland (Luke), Eteläranta 55, FI-96300 Rovaniemi, Finland E-mail: ristjal@gmail.com
• Blumenstein, Forest Pathology Research Group, Department of Forest Botany and Tree Physiology, Faculty of Forest Sciences and Forest Ecology, University of Goettingen, Büsgen-Institute, Büsgenweg 2, D-37077 Göttingen, Germany E-mail: kathrin.blumenstein@uni-goettingen.de