Hymenoscyphus fraxineus (ash dieback).

2021 ◽  
Author(s):  
Jessica Needham ◽  
Joan Webber
Keyword(s):  
North Africa ◽  
Fungal Pathogen ◽  
The Other ◽  
New Disease ◽  
Ash Dieback ◽  
South West ◽  
Hymenoscyphus Fraxineus ◽  
Natural Range

Abstract H. fraxineus is an anamorphic fungal pathogen that causes ash dieback. Due to the severity of ash dieback H. pseudoalbidus has been on the EPPO Alert list since 2007. It is not known what caused the emergence of this 'new' disease (NAPPO, 2009). Its spread in Europe is thought to be mainly by ascospores, but infected nursery saplings may carry the fungus to new areas. The entire natural range of known hosts, including North Africa, Russia and south-west Asia (USDA-ARS, 2009), is currently threatened by ash dieback, with large areas already affected (Pautasso et al., 2013). Little is known about the susceptibility of the other species of ash in temperate zones.

scholarly journals Rising out of the ashes: additive genetic variation for susceptibility to Hymenoscyphus fraxineus in Fraxinus excelsior

2015 ◽  
Author(s):  
F. Muñoz ◽  
B. Marçais ◽  
J. Dufour ◽  
A. Dowkiw
Keyword(s):  
Genetic Variation ◽  
Fraxinus Excelsior ◽  
Narrow Sense ◽  
Narrow Sense Heritability ◽  
Ash Dieback ◽  
Family Effects ◽  
Hymenoscyphus Fraxineus ◽  
Natural Range ◽  
Spatio Temporal ◽  
Crown Dieback

AbstractSince the early 1990s, ash dieback due to the invasive ascomycete Hymenoscyphus fraxineus is threatening Fraxinus excelsior in most of its natural range. Previous studies reported significant levels of genetic variability for susceptibility in F. excelsior either in field or inoculation experiments. The present study was based on a field experiment planted in 1995, fifteen years before onset of the disease. Crown and collar status were monitored on 788 trees from 23 open-pollinated progenies originating from 3 French provenances. Susceptibility was modeled using a Bayesian approach where spatio-temporal effects were explicitly taken into account. Moderate narrow-sense heritability was found for Crown Dieback (CD, h2=0.42). This study is first to show that Collar Lesions are also heritable (h2=0.49 for prevalence and h2=0.42 for severity) and that there is significant genetic correlation (r=0.40) between the severities of both symptoms. There was no evidence for differences between Provenances. Family effects were detected, but computing Individual Breeding Values (IBV) showed that most of the genetic variation lies within families. In agreement with previous reports, early flushing correlates with better crown status. Consequences of these results in terms of management and breeding are discussed.

scholarly journals Rising Out of the Ashes: Additive Genetic Variation for Crown and Collar Resistance to Hymenoscyphus fraxineus in Fraxinus excelsior

2016 ◽  
Vol 106 (12) ◽  
pp. 1535-1543 ◽  
Author(s):  
Facundo Muñoz ◽  
Benoît Marçais ◽  
Jean Dufour ◽  
Arnaud Dowkiw
Keyword(s):  
Genetic Variation ◽  
Health Status ◽  
Fraxinus Excelsior ◽  
Narrow Sense ◽  
Narrow Sense Heritability ◽  
Ash Dieback ◽  
Family Effects ◽  
Hymenoscyphus Fraxineus ◽  
Natural Range ◽  
Crown Dieback

Since the early 1990s, ash dieback due to the invasive ascomycete Hymenoscyphus fraxineus is threatening Fraxinus excelsior in most of its natural range. Previous studies reported significant levels of genetic variability in susceptibility in F. excelsior either in field or inoculation experiments. The present study was based on a field experiment planted in 1995, 15 years before onset of the disease. Crown and collar status were monitored on 777 trees from 23 open-pollinated progenies originating from three French provenances. Health status was modeled using a Bayesian approach where spatiotemporal effects were explicitly taken into account. Moderate narrow-sense heritability was found for crown dieback (h2 = 0.42). This study is first to show that resistance at the collar level is also heritable (h2 = 0.49 for collar lesions prevalence and h2 = 0.42 for their severity) and that there is significant genetic correlation (r = 0.40) between the severities of crown and collar symptoms. There was no evidence for differences between provenances. Family effects were detected, but computing individual breeding values showed that most of the genetic variation lies within families. In agreement with previous reports, early flushing correlates with healthier crown. Implications of these results in disease management and breeding are discussed.

scholarly journals Phenotypic variability of Fraxinus excelsior L. and Fraxinus angustifolia Vahl under the ash dieback disease in the Czech Republic

2018 ◽  
Vol 64 (No. 6) ◽  
pp. 279-288
Author(s):  
Papić Slavica ◽  
Buriánek Václav ◽  
Longauer Roman ◽  
Kudláček Tomáš ◽  
Rozsypálek Jiří
Keyword(s):  
Phenotypic Variability ◽  
Fraxinus Excelsior ◽  
Ash Dieback ◽  
Hymenoscyphus Fraxineus ◽  
Forest Reproductive Material ◽  
Natural Range ◽  
Fraxinus Angustifolia ◽  
Reproductive Material ◽  
Dieback Disease

The study was carried out in the experiment with 16 provenances of common ash (Fraxinus excelsior Linnaeus) and 2 provenances of narrow-leaved ash (Fraxinus angustifolia Vahl) at a series of 5 parallel trial plots established in a gradient from lowland riverine to upland ravine sites. The role of the site, ash species and the provenance of common ash proved to have significant effects on the intensity of ash dieback (ADB) associated with the infection by Hymenoscyphus fraxineus (T. Kowalski) Baral, Queloz & Hosoya at the age of 20 years. Narrow-leaved ash was healthier, surviving and growing better than common ash on the trials situated inside as well as beyond its natural range. The ADB intensity was lower in the medium altitude and more easterly located trial plots with a more continental climate. The provenance of forest reproductive material proved to have a significant effect on the ADB damage and survival rate as well as the growth of ash across the trial plots of the experiment.

A Foothold in Paris

2017 ◽  
Author(s):  
Alison Forrestal
Keyword(s):  
Early Career ◽  
The Other ◽  
South West ◽  
University Level ◽  
Royal Household

This introductory chapter examines the early career of Vincent de Paul between 1581 and 1611, moving from his birth and education to his arrival in Paris in 1608, and his immersion in the dévot environment there. It begins with a summary of his birth in south-west France and his years of education to university level. It then outlines his appointment as an almoner in the royal household of Marguerite de Valois in early 1610, after he had taken up residence in Paris two years earlier. It concludes with an analysis of the other aspects of his material livelihood during these years, including his acquisition of the abbey of Saint-Léonard-de-Chaumes in western France.

scholarly journals A young man presenting with encephalopathy and seizures secondary to SARS-CoV-2

2021 ◽  
Vol 14 (3) ◽  
pp. e240576
Author(s):  
Bilal Athar Jalil ◽  
Mohsin Ijaz ◽  
Amir Maqbul Khan ◽  
Thomas Glenn Ledbetter
Keyword(s):  
Respiratory Illness ◽  
Viral Meningitis ◽  
The Other ◽  
New Disease ◽  
Unique Case ◽  
Multisystem Involvement ◽  
Disease Associations ◽  
Viral Illness ◽  
Structural Brain ◽  
New Onset

COVID-19 has now emerged from a respiratory illness to a systemic viral illness with multisystem involvement. There is still a lot to learn about this illness as new disease associations with COVID-19 emerge consistently. We present a unique case of a neurological manifestation of a patient with structural brain disease who was COVID-19 positive and developed mental status changes, new-onset seizures and findings suggestive of viral meningitis on lumbar puncture. We also review the literature and discuss our case in the context of the other cases reported. We highlight the value of considering seizures and encephalopathy as one of the presenting features of COVID-19 disease.

scholarly journals Assessing Genotypic and Environmental Effects on Endophyte Communities of Fraxinus (Ash) Using Culture Dependent and Independent DNA Sequencing

2021 ◽  
Vol 7 (7) ◽  
pp. 565
Author(s):  
Anindita Lahiri ◽  
Brian R. Murphy ◽  
Trevor R. Hodkinson
Keyword(s):  
Community Composition ◽  
Environmental Effects ◽  
High Throughput Sequencing ◽  
Fungal Community Composition ◽  
Species Identity ◽  
Ash Dieback ◽  
Hymenoscyphus Fraxineus ◽  
Culture Independent ◽  
The Impact ◽  
Culture Dependent

Fraxinus excelsior populations are in decline due to the ash dieback disease Hymenoscyphus fraxineus. It is important to understand genotypic and environmental effects on its fungal microbiome to develop disease management strategies. To do this, we used culture dependent and culture independent approaches to characterize endophyte material from contrasting ash provenances, environments, and tissues (leaves, roots, seeds). Endophytes were isolated and identified using nrITS, LSU, or tef DNA loci in the culture dependent assessments, which were mostly Ascomycota and assigned to 37 families. Few taxa were shared between roots and leaves. The culture independent approach used high throughput sequencing (HTS) of nrITS amplicons directly from plant DNA and detected 35 families. Large differences were found in OTU diversity and community composition estimated by the contrasting approaches and these data need to be combined for estimations of the core endophyte communities. Species richness and Shannon index values were highest for the leaf material and the French population. Few species were shared between seed and leaf tissue. PCoA and NMDS of the HTS data showed that seed and leaf microbiome communities were highly distinct and that there was a strong influence of Fraxinus species identity on their fungal community composition. The results will facilitate a better understanding of ash fungal ecology and are a step toward identifying microbial biocontrol systems to minimize the impact of the disease.

A Review on Adenocarpus mannii; a Main Species of the Genus Adenocarpus

2020 ◽  
Vol 6 (1) ◽  
pp. 3-12
Author(s):  
Blaise K. Nganou ◽  
Jubie Selvaraj ◽  
Pierre Tane ◽  
Alex Nchiozem ◽  
Ingrid Simo ◽  
...  
Keyword(s):  
North Africa ◽  
Southern Italy ◽  
Tropical Regions ◽  
The Third ◽  
West Region ◽  
South West ◽  
Agriculture Industry ◽  
Microbial Infections ◽  
Chemotaxonomic Markers ◽  
Phytochemical Studies

: The fabaceae are rooted in rosaceae pods known as "vegetables" by the early botanists. They are the third family of angiosperms which includes 642 genus divided into about 18,000 species. The fabaceae family is known as the most important family of the ecosystem as it is indispensable in medicine, agriculture, industry and livestock. The Adenocarpus genus has about 50 species that are frequently found in tropical regions of Northern Africa, the southern part of West Europe and in the central and southern Italy. They are used in traditional medicine for the treatment of several diseases: such as microbial infections, leprosy, scabies, acne, malaria and other plants species are used in agriculture as insecticidal properties. Mainly Adenocarpus mannii species is well represented in the tropical regions of North Africa. It occurs in Angola, Mozambique, Malawi, Guinea, South Africa, Tanzania, and Burundi. In Cameroon, it is encountered in South West Region and West Region. Previous phytochemical studies led to the isolation of several classes of compounds such as flavonoids, alkaloids and triterpenes. Several studies report the phytochemical studies on genus Adenocarpus and chemotaxonomic markers of species of this genus. Herein, we outline all the botanical, pharmacological and phytochemical aspects of Adenocarpus mannii. A brief introduction about fabaceae and the genus Adenocarpus has also been included.

scholarly journals Courage and Cowardice in the North African Campaign: The Eighth Army and Defeat in the Summer of 1942

2013 ◽  
Vol 20 (1) ◽  
pp. 99-122 ◽  
Author(s):  
Jonathan Fennell
Keyword(s):  
North Africa ◽  
The State ◽  
The Other ◽  
Human Dimension ◽  
North African ◽  
The North ◽  
High Level ◽  
Eighth Army

High rates of desertion and surrender during the battles in North Africa in the summer of 1942 were a major factor in Eighth Army’s poor combat performance. At the time, some suggested that these problems were symptomatic of a lack of courage or even of cowardice. There are two broad strands to the conceptualization of courage and cowardice. One focuses on the willingness of the person to fight; the other puts emphasis on how actions express an individual’s ability to cope with fear. Whichever conceptualization is used, high morale motivates the soldier to fight and shields the ordinary recruit from his fear, preventing it from overcoming him in battle. Where morale fails, the soldier is left demotivated and burdened with his terror and, therefore, and is therefore prone to desertion or surrender. Because it is extremely difficult to maintain morale at a continuously high level in an environment governed by chance and managed by humans, all soldiers can find themselves in situations where their actions may be judged as cowardly. Alternatively, if they are properly motivated to fight and prepared by the state and military to deal with the unavoidable fear of combat, all soldiers can be labelled courageous. Accordingly, emotive terms should be avoided when attempting to describe rationally explainable outcomes. The undoubtedly negative connotations attached to cowardice in battle and the positive ones attached to courage are, therefore, arguably unhelpful in understanding Eighth Army’s performance in the summer of 1942 and the human dimension in warfare more generally.

Description, distribution and ecology of endemic Tasmanian quillwort, Isoetes jarmaniae, sp. nov. (Isoetaceae; Lycopodiopsida)

Phytotaxa ◽  
2021 ◽  
Vol 522 (1) ◽  
pp. 27-37
Author(s):  
DANIEL F. BRUNTON ◽  
MICHAEL GARRETT ◽  
PAUL C. SOKOLOFF ◽  
GINTARAS KANTVILAS
Keyword(s):  
Diploid Species ◽  
Geographic Range ◽  
The Other ◽  
South American ◽  
The South ◽  
Triangular Shape ◽  
South West ◽  
Distribution And Ecology ◽  
River Valleys

Isoetes jarmaniae sp. nov. is described as a new lycophyte endemic to Tasmania, Australia, where it is confined to peat-bound karstic wetlands in several river valleys in the south-west wilderness. While seemingly morphologically closest to I. drummondii, this quillwort has features that are globally uncommon in Isoetes and unknown in other Australasian taxa. Most notable are its markedly flattened, strongly recurved leaves and disproportionately large sporangium ligules that are more suggestive of South American than Australian taxa. As well, the exceptionally thin and wide (alate) megaspore equatorial ridge is swollen at suture intersections, presenting a slightly triangular shape suggestive of the Indian taxon I. udupiensis. The microspores of I. jarmaniae exhibit exceptionally, perhaps uniquely, fine-papillate ornamentation. An original key placing I. jarmaniae in context with the other Tasmanian Isoetes species is provided. This diminutive, apparently diploid species is evidently maintaining a self-sustaining population within a regionally unique habitat and small geographic range.

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