Synergistic negative effects of ash dieback and Armillaria root rot on health and stability of mature ash trees

Forest Ecology and Management, Год журнала: 2025, Номер 580, С. 122476 - 122476

Опубликована: Фев. 8, 2025

Язык: Английский

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Ash dieback assessments on intensive monitoring plots in Germany: influence of stand, site and time on disease progression

Journal of Plant Diseases and Protection, Год журнала: 2024, Номер unknown

Опубликована: Март 29, 2024

Abstract Since 2002, ash dieback caused by the invasive fungus Hymenoscyphus fraxineus has been observed in Germany. The pathogen and its associated symptoms have fatal consequences for vitality survival of European ( Fraxinus excelsior L.), an economically ecologically important tree species. This study analyses monitoring results eleven intensive plots FraxForFuture research network distributed across Germany focuses on within-stand differences dependence small-scale site properties. A cohort 1365 trees was surveyed six times over three years, testing applying a summer winter version nationally standardised assessment key. main disease (crown basal lesions) were more pronounced areas with higher density, edaphically moist (hydromorphic soils), younger/smaller trees, generally increased time. However, trend time differed between single plots. In case considering only surviving part populations, crown condition even improved 6/11 plots, indicating selection process. Large lesions at beginning observation period very good predictor deadfall probability, especially lower stem diameter. Generally, related highly correlated. Silvicultural management practice past that actively pushed towards moister end water demand spectrum to be questioned light dieback. Cost-intensive re-cultivation future—possibly less dieback-susceptible progenies—should avoid pure stands hydromorphic soil conditions.

Язык: Английский

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Pathogenic fungi and oomycetes causing dieback on Fraxinus species in the Mediterranean climate change hotspot region

Frontiers in Forests and Global Change, Год журнала: 2023, Номер 6

Опубликована: Авг. 25, 2023

Environmental changes are occurring on a global scale, but their effects most pronounced in climate change hotspot zones, such as the Mediterranean basin. Within this area Italy, extending from its southern coasts core of Sea to northernmost pre-Alpine and Alpine regions, is characterized by variety climatic conditions vegetation types. Surveys conducted 2018–2022 forest formations Central-Northern Italy revealed that enhanced warming trend irregular distribution precipitations strongly impacting health Fraxinus species, with some pathogenic fungi oomycetes being important contributing factors decline three main ash species growing there: common ( excelsior ), flowering ornus narrow-leaved angustifolia ). Isolation symptomatic plant material collected countrywide under different site pathogenicity tests complex phytopathological framework, several addition Hymenoscyphus fraxineus involved prominent role dieback etiology. Key microbial taxa included fungal oomycete pathogens Botryosphaeria dothidea , Diplodia fraxini subglobosa Phytophthora acerina plurivora . The disease impact was higher sites where trees grew environmental stress (i.e., areas mild dry winters, hot summers intense prolonged drought) exhibited reduced vigor, also consequence anthropogenic interference silvicultural management fires). identified causative agents emerging thrive warmer conditions, investigated prevalent compared H. which appears be restricted Italian peninsula cooler wetter valleys Alps Apennines.

Язык: Английский

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Fungi associated with fine roots of Fraxinus excelsior affected by ash dieback detected by next-generation sequencing

Journal of Plant Diseases and Protection, Год журнала: 2024, Номер 131(5), С. 1373 - 1385

Опубликована: Май 4, 2024

Abstract The decline of European ash by dieback caused Hymenoscyphus fraxineus together with stem collar necroses and rots various fungi has been investigated intensively during the last years. Nevertheless, hitherto nearly nothing is known about species diversity fungal rhizobiome trees. Here we fine roots affected trees on 15 sampling sites in 6 federal countries Germany. Fine-root samples have treated three different sample regimes each as root-adhering soil, unsterilized sterilized roots. were pooled to get an overview species-richness area. next-generation sequencing platform Oxford Nanopore MinION was used sequence entire ITS probes. Most abundant phyla all Basidiomycota Ascomycota. Species richness significantly from soil. Surprisingly most genera Mycena , Mycenella Delicatula, them agaricoids saprophytic lifestyle. Eleven Glomeromycota detected abundances, whereas detection H. neglectable.

Язык: Английский

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Hope for ash conservation and propagation—single individuals can be highly resistant to an invasive pathogen

Journal of Plant Diseases and Protection, Год журнала: 2024, Номер 132(1)

Опубликована: Дек. 11, 2024

Abstract Common ash ( Fraxinus excelsior L.) has been considered an important candidate species for climate-resilient forest management in Germany. The occurrence of dieback, caused by the invasive fungus Hymenoscyphus fraxineus , severely limits its use. However, less damaged trees heavily infested stands are observed. This suggests a tree-specific and genetically determined susceptibility to dieback. potential individual selection conservation programs investigated on 35 clones clonal trial 30 families progeny since 2014. Ash dieback-related mortality, crown damage, height growth were examined. Resistance dieback was evaluated based multi-year observations. Mortality ramets occurred rapidly damage stabilized, whereas steadily increasing during study period. About 34 percent all offspring (0–56 per family) showed high resistance 10 also good growth. Broad-sense heritability narrow-sense moderate comparable previous studies. We assume that at least some individuals from specific progenies will resist disease stands. In situ ex strategies should be promoted. Seed orchards with more resistant genotypes could provide susceptible reproductive material, breeding help accelerate fixation favorable alleles.

Язык: Английский

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Priming of ash saplings with a low virulent Hymenoscyphus fraxineus strain as a possible disease control approach for reducing symptoms of ash dieback

Journal of Plant Diseases and Protection, Год журнала: 2025, Номер 132(2)

Опубликована: Янв. 31, 2025

Язык: Английский

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Temperature-related growth limits and wood decay capacity of the warmth-loving fungus Biscogniauxia nummularia in vitro

Frontiers in Fungal Biology, Год журнала: 2025, Номер 6

Опубликована: Апрель 11, 2025

Temperature-related growth characteristics and wood decay capacities of Biscogniauxia nummularia strains were analysed in vitro , revealing variability between strains. To model the fitted dose-response curves generated using four-parameter Brain-Cousens hormesis model. The different showed distinct optimum temperatures, with some achieving maximum at 25°C, while others peaked 28°C, depending on tested culture media. Strains also exhibited variation their temperature ranges for measurable growth, tolerating a broader range than others. results study lead to consideration that tolerance as well optimal might be influenced by strains’ geographic origin, those from southern Germany possibly adapted higher temperatures. In terms decay, mass loss caused various differed clearly many cases, suggesting potential strain-dependent differences pathogenicity. Additionally, genetic analysis beta-tubulin DNA region B. specimens examined revealed considerable variations

Язык: Английский

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Diplodia fraxini: The Main Pathogen Involved in the Ash Dieback of Fraxinus angustifolia in Croatia

Microorganisms, Год журнала: 2025, Номер 13(6), С. 1238 - 1238

Опубликована: Май 28, 2025

Fraxinus angustifolia, the main ash species in Croatia terms of economic and ecological importance, is affected by a severe dieback initially attributed to fungal pathogen Hymenoscyphus fraxineus. Recently, another pathogen, Diplodia fraxini, has been shown play key role several European countries. Therefore, because symptoms trees observed are typical Botryosphaeriaceae attacks, aim this study was define etiology F. angustifolia dieback. To end, symptomatic shoots branches cross-sections stem were sampled from 20 at eight locations analyzed for presence D. fraxini other possible pathogens. fungus most frequently associated with branch cankers dieback; it isolated 17 all sites monitored, its pathogenicity towards confirmed. The also wood necrosis base trunk two trees. Other fungi, namely H. fraxineus, Diaporthe eres, seriata, Botryosphaeria dothidea, Armillaria gallica, Lentinus tigrinus, sporadically.

Язык: Английский

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Priming of ash saplings with a low virulent Hymenoscyphus fraxineus strain as a possible disease control approach for reducing symptoms of ash dieback

Research Square (Research Square), Год журнала: 2024, Номер unknown

Опубликована: Май 9, 2024

Ash dieback is a tree disease caused by the fungal pathogen Hymenoscyphus fraxineus. Since its introduction into Europe, it has widespread and significant losses of European ash, Fraxinus excelsior. Inoculations F. excelsior with low virulent H. fraxineus isolate was assessed as promising method for reducing symptoms associated ash dieback, presumably triggering systemic induced resistance. Two strains were chosen based on observations high in planta virulence. Crude extracts obtained from cultures highly strain more phytotoxic leaf puncture assay than ones strain. UHPLC-DAD-MS/MS data identified phytotoxin viridiol potential hyfraxin A both cultures. However, production these compounds vitro did not correspond virulence planta. To test effects priming, saplings first inoculated subsequently On average, necrosis expansion stems reduced 54% primed at end monitoring period 14 weeks, thus providing proof concept priming. These results contribute to our understanding possible integrated biological control approach increasing resistance damages pathogens, particularly during nursery propagation, out-planting through establishment phase. We discuss context relevant literature summarise limited availability priming underlying principles trees.

Язык: Английский

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Fungal Presence and Changes of Wood Structure in Bark Stripping Wounds Made by Red Deer (Cervus elaphus L.) on Stems of Fraxinus angustifolia (Vahl)

Forests, Год журнала: 2024, Номер 15(2), С. 314 - 314

Опубликована: Фев. 7, 2024

Narrow-leaved ash (Fraxinus angustifolia Vahl), a highly valued European forest tree species, has been severely affected by large-scale decline, which is most probably driven complex of multiple interacting factors including fungi, contribute to and accelerate this process. Red deer (Cervus elaphus L.) can be considered as one the contributing factors, they inflict damage on stems young trees stripping bark. These wounds not only represent suitable entry points for fungi cause tissue necroses decomposition, lead changes in wood structure well. The aims research were analyze chosen parameters bark narrow-leaved stands, identify present exposed wounding, inspect effect wounding structure. Bark was observed from 2 cm up 18 DBH between 0.1 m 1.9 stem height. susceptible those with an average 5 ± 2.5 cm. On (51%), one-third two-thirds circumference damaged. In wounded tissue, 174 fungal isolates found, belonged known endophytic genera Trichoderma, Fusarium, Clonostachys. It that earlywood cells zone had narrower lumens compared ones adjacent healthy regard different heights.

Язык: Английский

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