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... The ongoing fragmentation of ash populations due to ash dieback requires an effective gene flow between individuals; thus, investigations on ash pollen transport are essential. In this study, comprehensive aerobiological field experiments at two seed plantations in Baden-Württemberg were conducted in 2019 and 2020 in order to study the influence of phenology and meteorology (especially wind) on po ...
Eucalyptus; algorithms; data collection; death; dieback; ecological balance; farms; image analysis; lidar; time series analysis; trees; Australia
Abstract:
... Rapid decline and death of rural Eucalypts trees of all ages and species have been reported in the farmscapes of regional Australia due to various environmental and farming management related factors. The identification of existing farm tree species is important for long term management strategies to provide ecosystem stability in the region. This study explored the feasibility of structural attri ...
... Eutypa dieback and Esca are serious fungal grapevine trunk diseases (GTDs). Eutypa dieback is caused by Eutypa lata (Elata), and is often associated Phaeoacremonium minimum (Pmin), and Phaeomoniella chlamydospora (Pch) which are also important contributors to Esca disease. Understanding the complex pathogenesis mechanisms used by these causative fungi may potentially lead targeted treatments for G ...
... The scientific understanding regarding sources, occurrence, and effects of microplastics in the aquatic environment has advanced rapidly, leaving some meaningful knowledge gaps virtually untouched. One of them is the interactions of microplastics and biofilms, microbial communities ubiquitous in aquatic ecosystems and fundamental for a range of ecosystem‐level processes. It is evident that biofilm ...
... Climate change triggered forest die-back is a huge concern worldwide. Arboretums and common gardens comparing geographic origins within species can provide a large body of valuable information and material usable to increase forest resilience. Common gardens have been foundational in demonstrating the existence of genetic diversity, local adaptation and phenotypic plasticity. They have also been i ...
... Hazelnut (Corylus avellanae), a plant native to the temperate northern hemisphere, is cultivated in Iran mainly in the northern parts of the country. Irregular reddish-brown necrotic spots surrounded by a yellow halo on hazelnut leaves and fruit bracts, leading to wilting of leaves, defoliation, and branch dieback, were observed during 2018 and 2019 in hazelnut orchards of the Guilan province. Iso ...
... The number of reports associated with wood dieback caused by fungi in the Botryosphaeriaceae in numerous perennial crops worldwide has significantly increased in the past years. In this study, we investigated the interactions between the canker pathogen Neofusicoccum parvum and the almond tree host (Prunus dulcis), with an emphasis on varietal resistance and host response at the cell wall biochemi ...
... Grevillea robusta (Proteaceae) is an economically important plant species. In Sri Lanka, G. robusta is a popular high shade tree in tea plantations and is widely grown in high and mid-elevations (> 600 m mean sea level). Incidences of canker and associated die-back of G. robusta are increasing on tea lands of Sri Lanka. The symptoms started from yellowing and defoliation of leaves, and the death o ...
... In a recent survey of olive groves in the Southeast Anatolia Region of Turkey, a new and serious decline of olive trees, beginning with foliar scorching and then dieback of twigs, branches, and even whole trees, was observed for the first time. In more advanced stages of the disease, necrosis and cankers were observed on the bark of the trunk, branches, and twigs. Isolations from symptomatic tissu ...
Caragana korshinskii; Ulmus pumila; canopy; climate; dieback; drought; ecological balance; forests; land degradation; sap flow; soil erosion; soil water; soil water content; stomatal conductance; vapor pressure deficit; water conservation; water stress; China
Abstract:
... Constructing protective forests to control water and soil erosion is an effective measure to address land degradation in the Bashang Plateau of North China, but forest dieback has occurred frequently due to severe water deficits in recent decades. However, transpiration dynamics and their biophysical control factors under various soil water contents for different forest functional types are still ...
... Fe biogeochemistry is associated with important ecosystem services provided by mangrove forests, including carbon sequestration and the retention of potentially toxic elements. The biogeochemical processes controlling Fe fate in mangroves are naturally affected by the soil geochemical environment, which controls Fe dynamics. However, ongoing climate changes and the associated extreme weather event ...
... Verticillium wilt, caused by Verticillium dahliae is considered the most serious biotic threat to olive trees. The disease is detected in almost all regions where olive is cultivated, and it may cause olive decline and dieback. The aim of this study was to determine the incidence and distribution of Verticillium wilt on olive trees in Istria (Croatia), to identify pathotype groups and race structu ...
... Botryosphaeria dothidea is, globally, one of the most economically important phytopathogenic fungi worldwide, causing the canker and dieback of fruit trees. An increasing number of viruses infecting B. dothidea have lately been reported, several of which could confer hypovirulence. In this study, isolated from strain ZM170285-1 of B. dothidea, a novel double-stranded RNA (dsRNA) mycovirus, tentati ...
carbon sequestration; climate; climate change; dieback; econometric models; forest policy; land use; market share; net primary productivity; timber production; Brazil; Canada; Chile; Latin America; Uruguay
Abstract:
... This paper examines the potential impact of climate change on forests and timber production in Latin America. The analysis links a Dynamic Global Vegetation Model (DGVM), which projects forest migration, forest dieback, and net primary productivity spatially as a function of future climate predictions, with a dynamic optimization model of global timber markets. A global model is used because clima ...
... Cities have been described as ‘heat islands’ and ‘dry islands’ due to hotter, drier air in urban areas, relative to the surrounding landscape. As climate change intensifies, the health of urban trees will be increasingly impacted. Here, we posed the question: Is it possible to predict urban tree species mortality using (1) species climate envelopes and (2) plant functional traits? To answer these, ...
Abies concolor; Cytospora; Sydowia polyspora; abiotic stress; dieback; discoloration; fungi; ornamental trees; plant protection; vegetation; Serbia; Southern European region
Abstract:
... Abies concolor was introduced to Europe in the 19th century and commonly planted as an ornamental tree. In 2018, after several very warm and dry vegetation seasons, which has likely caused abiotic stress in the trees, a sudden dieback of A. concolor was observed in the city of Aranđelovac in Serbia. The external symptoms were the rapid discoloration of needles in a larger part of the cr ...
... ‘Candidatus Liberibacter’ species are associated with severe, economically important diseases. Nearly all known species are putatively insect transmitted, specifically by psyllids. Detection of ‘Ca. Liberibacter’ in plants is complicated by their uneven distribution in host plants and largely fastidius nature. The death of black (Fraxinus nigra) and mancana (Fraxinus mandshurica) ash trees in Sask ...
Fagus sylvatica subsp. sylvatica; climate; death; dieback; drought; growth rings; hardwood; mortality; tree health; tree mortality
Abstract:
... Widespread increases in tree mortality have fueled the debate on the mechanisms of heat- and drought-related tree death. While much research focused on the immediate causes of tree death, the role of predisposing factors for death is not well understood. We employed tree-ring and climate sensitivity analysis of growth to study the importance of legacy effects of past disturbances for growth patter ...
... The relationships between different aspects of diversity (taxonomic, structural and functional) and the aboveground biomass (AGB) as a major component of global carbon balance have been studied extensively but rarely under the simultaneous influence of forest dieback and management. In this study, we investigate the relationships between taxonomic, functional and structural diversity of woody spec ...
... An undescribed disubstituted dihydrofuranone, named diplofuranoxin, was isolated, together with the six well known metabolites sphaeropsidins A and C, epi-sphaeropsidone, mellein and cis- and trans-4-hydroxymelleins, from the fungal species Diplodia subglobosa, an emerging pathogen involved in the ash dieback aetiology in Europe. Currently, the disease represents the main threat to European ash he ...
... Blueberries (Vaccinium corymbosum) have been increasingly cultivated in Portugal. Although blueberry is known to be susceptible to twig blight and dieback caused by pestalotioid fungi, there is still scarce information regarding this issue. To bridge this gap, a survey on blueberry plantations in Portugal was carried out to assess the diversity of pestalotioid fungi associated with symptomatic blu ...
... Family Botryosphaeriaceae and the genus Diaporthe (family Diaporthaceae) represent diverse groups of plant pathogens, which include causal agents of leaf spot, shoot blight, branch and stem cankers, dieback, and pre- and postharvest apple fruit decay. Apple fruit with symptoms of light to dark brown decay were collected during and after harvest from 2016 to 2018. Thirty selected isolates, on which ...
... Prescribed fire is a widespread management practice in fire-prone ecosystems that can have significant effects on fauna. To inform the development of appropriate prescribed burning regimes, we explored bird responses to time since fire in threatened Banksia woodlands in south-western Australia. We used area searches to estimate bird densities on 20 plots ranging from 1 to 26 years post fire ...
... Ash disease caused by ascomycete fungus Hymenoscyphus fraxineus leads to the retreat of ash, particularly in ash-dominated stands characterized by moist, fertile, and neutral soils. Thus, it has a more severe impact on species regeneration and survival in ash optimal sites. We aimed to investigate the joint effects of seed dispersal limitation triggered by the distance from seed source, as well as ...
... Forest ecosystems are increasingly exposed to the combined pressure of climate change and attacks by pests and pathogens. These stress factors can threaten already vulnerable species triggering dieback and rising defoliation and mortality rates. To characterize abiotic (drought, climate warmings) and biotic (pathogens) risks and their spatiotemporal patterns we quantified the recent loss of vitali ...
... In recent years, new fungal diseases in kiwifruits have emerged worldwide. This study is the first report of a postharvest kiwifruit rot in South Korea caused by Diaporthe eres and related fungal pathogens. After single spore isolation of Diaporthe-like fungi isolated from rotten kiwifruits, isolates were identified based on the multi-locus phylogeny using the nuclear rDNA internal transcribed spa ...
... The creation of artificial dunes for coastal protection may have important consequences for freshwater lenses in coastal aquifers. The objective of this study was to compare the recharge processes below such a young dune with scant vegetation to an older dune covered by grass and herbaceous vegetation. To this aim, soil and water samples were collected from the unsaturated zone at two sites on Lan ...
... Hymenoscyphus fraxineus, causal agent of Ash Dieback, has posed a threat to Fraxinus excelsior (common ash) in Europe since the 1990s. In south-western Europe, optimal climatic conditions for H. fraxineus become scattered and host density decreases, reducing disease spread rates. To date, the Ash Dieback agent has not been reported from southern and most of central Italy, where native F. excelsior ...
Amado O. Cortez Jr.; Cheng‐Lung Chu; Hannah J. Broadley; Yong‐Sin Lo; Yu‐Chun Chen; Michael W. Gates; Laura A. Meyerson; Kim A. Hoelmer; Juli R. Gould; Shaw‐Yhi Hwang
... Roseau cane (Phragmites australis (Cav). Trin. ex Steud.) is the dominant plant species of the Mississippi River Delta in Louisiana, USA, and protects the coastline from erosion and storm‐related impacts, maintaining shipping channels and oil infrastructure. Widespread dieback and thinning of P. australis were noted in the Mississippi River Delta in the fall of 2016. Invasive populations of the ro ...
... Pathogens that attack invasive plants can positively affect the integrity and functioning of ecosystems. Stem-tip dieback and extensive wilting followed by sudden death have been observed in Chrysanthemoides monilifera subsp. rotundata (bitou bush), one of Australia’s worst invasive shrubs. Metabarcoding and culturing methods were used to investigate whether fungi are implicated in this syndrome. ...
... Tree mortality during global‐change‐type drought is usually attributed to xylem dysfunction, but as climate change increases the frequency of extreme heat events, it is necessary to better understand the interactive role of heat stress. We hypothesized that some drought‐stressed plants paradoxically open stomata in heatwaves to prevent leaves from critically overheating. We experimentally imposed ...
... In 2019, a decline of Quercus emoryi (Emory oak) was observed on the Coronado National Forest located in southeastern Arizona. Symptoms associated with oak mortality included crown dieback and large cankers revealing charcoal-like stromal growth. Trunks and root collars showed girdling, and many affected trees also displayed evidence of gold-spotted oak borer activity. Initial surveys in stands id ...
... Tartary buckwheat (Fagopyrum tataricum, Polygonaceae) is an annual plant originating in Southwest China. It has a short growth cycle, barren soil tolerance, and strong stress resistance (Zhang et al. 2021). Because of its high content of proteins, starch, trace elements, phenols, and dietary fiber, Tartary buckwheat is beneficial to the human body and hence has received widespread attention (Joshi ...
... Botryosphaeria dothidea is a fungal pathogen commonly associated with stem canker, dieback, and rot disease in a variety of woody plants worldwide (Dong and Guo 2020). In Korea, B. dothidea was reported to cause a disease in several crops such as apple and blueberry (Choi 2011; Kim 1995). In early 2020, a symptom resembling stem rot disease occurred at a plumcot cultivation area around Wanju Provi ...
... Tea (Camellia sinensis) is a significant commercial crop in China. A collar canker and dieback disease of tea has recently been reported in Sri Lanka (Sinniah et al. 2017). In spring 2020, tea bushes with symptoms of fewer leaves, yellowing of leaves with cankers having cracks, and peeling of bark, premature falling in the early stage, and progressive dieback of branches followed by death of the w ...
... Blueberry (Vaccinium virgatum), an economically important small-fruit crop, is characterized by its highly nutritive compounds and high content and wide diversity of bioactive compounds (Miller et al. 2019). In September 2020, an unknown leaf blight disease was observed on ‘Rabbiteye’ blueberry at the Agricultural Science and Technology Park of Jiangxi Agricultural University in Nanchang, China (2 ...
... Rose (Rosa sp.) is an important floricultural crop largely cultivated in the Karnataka state of southern India. A field survey conducted in the Devanahalli, Bangalore rural area during October 2019 revealed rose plants (cv. Arka Pride) showing dieback symptoms with a disease incidence of 7% in a 30-ha rose field. Dieback was characterized by the development of necrotic lesions that started at the ...
... In June 2017, three vineyards were surveyed in the regions of Droushia (30-year-old cv. Mavro), Ineia (50-year-old cv. Xynisteri), and Lemona (15-year-old cv. Carignan) in the province of Paphos, Cyprus, with dieback incidence of 22, 32, and 14%, respectively. More specifically, affected grapevines exhibited severe dieback symptoms in spur and cordon positions, related to perennial cankers and int ...
... Golden or giant chinquapin, Chrysolepis chrysophylla (Fagaceae), is a slow-growing, evergreen shrub or tree native to the west coast of the United States (Niemiec et al. 1995). In April 2015, several declining chinquapin trees were identified on Bolinas Ridge near Mt. Tamalpais in Marin County, California, a Phytophthora ramorum infested region (Rizzo et al. 2002). Affected trees were large overst ...
... In recent decades the vitality and productivity of European ash trees in Slovenia have been reduced by the onset of canker and dieback disease symptoms on young and old trees, identified primarily as ash dieback caused by Hymenoscyphus fraxineus. Given the limited information available about the etiology of this emerging disease, a study was carried out to isolate, identify, and characterize the f ...
... Boxelder (Acer negundo) is a tree native to North America. In Europe it is considered a dangerous invasive species, and assigned to the highest (fourth) category of environmental hazard (Tokarska-Guzik et al. 2012). The tree can threaten a wide range of ecosystems and compete with the native flora. Shoot dieback was observed on 20% of boxelder in July 2018 and 2019 in Bryzgiel (N53°59.963′ E23°04. ...
... Pleurostoma richardsiae has been described as an olive tree pathogen causing decline and brown wood streaking (Carlucci et al. 2013). A survey was carried out in plots under olive cultivation (Olea europaea L., cv. Picual; 10-year-old plants) at La Garrovilla, Spain, in September 2020 in which a putative Verticillium wilt had been visually diagnosed. In plot 1 (2.6 ha; 741 plants), 20.4% of the pl ...
... Species of Pestalotiopsis occur commonly as plant pathogens. Accordingly, the aim of this study was to identify the causal agent of a shrub disease in northeastern and northern Tunisian forests. Field surveys showed a progressive dieback of branches, twig blight and trunk cankers on Pistacia lentiscus and Quercus coccifera. Pestalotiopsis spp. were the main fungi consistently isolated from these s ...
Luiz Blaine C.; Giardina Christian P.; Keith Lisa M.; Jacobs Douglass F.; Sniezko Richard A.; Hughes Marc A.; Friday James B.; Cannon Philip; Hauff Robert; Francisco Kainana; Chau Marian M.; Dudley Nicklos; Yeh Aileen; Asner Gregory; Martin Roberta E.; Ryan Perroy; Brian J. Tucker; ʻAleʻalani Evangelista; Veronica Fernandez; Chloe Martins-Keliʻihoʻomalu; Kirie Santos
... Metrosideros polymorpha Gaud. ('ohi'a) is the most abundant native forest tree in Hawai'i and a keystone species of cultural, ecological, and economic importance. However, stands of M. polymorpha are being severely impacted by Rapid 'Ohi'a Death (ROD), which is characterized by branch dieback, crown wilting, and mortality. Research revealed that ROD is caused by two novel species of Ceratocystis p ...
Agrilus planipennis; Fraxinus excelsior; Fraxinus pennsylvanica; Hymenoscyphus fraxineus; Russia; dieback; ecology; fungi; inventories; larvae; Baltic Sea; North America
Abstract:
... The emerald ash borer (EAB), Agrilus planipennis, is an invasive beetle of East Asian origin that has killed millions of ash trees (Fraxinus spp.) in North America and Russia. In September 2020, EAB was detected in Saint Petersburg, a notable event for the metropolitan city. The aim of the present study was to investigate the occurrence and ecology of EAB in Saint Petersburg. The presence of two d ...
... For years, Japanese knotweed (Reynoutria japonica) has been suspected of accelerating riverbank erosion, despite a lack of convincing evidence. The stems of this invasive plant die back following the first autumn frosts, leaving the soil unprotected during winter and spring floods. In Québec (Canada), riverbank erosion may also be accentuated by ice during mechanical ice breakups. The objective of ...
... Leaf abundance of trees plays a dominant role in energy, water and nutrient flux of forest ecosystems, in defining the habitat structure of entrained biota and in mediating interspecific competition among tree species. We quantified leaf abundance of three dominant tree species (Acer saccharum Marsh.; Fagus grandifolia Ehrh.; Betula alleghaniensis Britt.) for 27 years in mature northern hardwood f ...
Fagus sylvatica subsp. sylvatica; decline; dieback; drought; forests; meteorology; species diversity; standard deviation; trees; Central European region; Switzerland
Abstract:
... European beech (Fagus sylvatica L.) has strongly suffered from the exceptional 2018 drought and subsequent dry years that hit Central Europe. While many trees showed severe signs of crown dieback or died following the 2018 extreme drought, other co-occurring and neighboring trees showed no sign of dieback or only minor damage. The reasons why some trees were more severely impacted than others and ...
... Peatlands of the Northern Hemisphere and Central European coniferous forests experience significant environmental change. The resultant browning of surface waters, that is, elevated concentrations of dissolved organic matter (DOM) and metals, is of interest in the context of the global C cycle, peatland and forest management, and water treatment. In an attempt to identify the causes of this proces ...
... ‘Candidatus Phytoplasma ulmi’, associated with elm yellows, shoot proliferation and dieback of elm (Ulmus) species trees was reported in United States of America and in many European countries. Until now its presence in elm trees in Poland has not been detected. In 2017–2018, during visual inspection of elm trees grown in four areas of southern Silesia Province leaf yellowing, shoot proliferation, ...