Citizen Science Uncovers Phytophthora ramorum as a Threat to Several Rare or Endangered California Manzanita Species

Plant Disease ◽  
2020 ◽  
Vol 104 (12) ◽  
pp. 3173-3182
Author(s):  
Matteo Garbelotto ◽  
Tina Popenuck ◽  
Brett Hall ◽  
Wolfgang Schweigkofler ◽  
Francesco Dovana ◽  
...  
Keyword(s):  
Phytophthora Ramorum ◽  
Sudden Oak Death ◽  
Santa Cruz ◽  
Forest Disease ◽  
Marin County ◽  
Interspecific Differences ◽  
Detached Leaves ◽  
Comparative Susceptibility ◽  
The University ◽  
First Time

The Sudden Oak Death (SOD) Blitzes consist of yearly surveys led by citizen scientists designed to map the distribution of Phytophthora ramorum, cause of the forest disease called SOD, across northern California. During the 2017 Santa Cruz County SOD Blitz, six rare or endangered Arctostaphylos (manzanita) species were found to be possibly symptomatic for the first time. Symptoms included branch cankers and associated canopy mortality, and affected multiple individuals per species. Isolates of P. ramorum were obtained from each of the six species and, through a 30-day-long inoculation experiment on live plants, Koch’s postulates were completed for each one of them, conclusively determining that they all are hosts of this pathogen. Two additional manzanita species were later found to be apparently symptomatic in Marin County. Inoculations on detached branches using an isolate of P. ramorum obtained from one of the six rare species from Santa Cruz County were successful, suggesting that these two species may also be hosts of P. ramorum. Detached leaves of all eight species were also successfully inoculated at the University of California-Berkeley in fall 2018 and then again in spring 2019. In these cases, the same isolate was used for all inoculations, in order to obtain information on the comparative susceptibility of the eight species in question. Both branch and leaf inoculations identified significant interspecific differences in susceptibility. The production of sporangia was low on all species but it was not zero, suggesting that sporulation may cause within-plant and limited across-plant contagion, especially in rainy years.

Forest transformation resulting from an exotic pathogen: regeneration and tanoak mortality in coast redwood stands affected by sudden oak death

2011 ◽  
Vol 41 (4) ◽  
pp. 763-772 ◽  
Author(s):  
Benjamin S. Ramage ◽  
Kevin L. O’Hara ◽  
Alison B. Forrestel
Keyword(s):  
Canopy Cover ◽  
Phytophthora Ramorum ◽  
Sudden Oak Death ◽  
Coast Redwood ◽  
Marin County ◽  
Wildlife Species ◽  
Management Interventions ◽  
Redwood Forests ◽  
Exotic Pathogen ◽  
Notholithocarpus Densiflorus

Sudden oak death is dramatically altering forests throughout coastal California, but little is known about the communities that are assembling in affected areas. This emerging disease, caused by the exotic pathogen Phytophthora ramorum (S. Werres, A.W.A.M. de Cock), has had especially severe effects on tanoak ( Notholithocarpus densiflorus (Hook. & Arn.) Manos, Cannon & S.H. Oh), a broadleaf evergreen that is abundant in forests dominated by coast redwood ( Sequoia sempervirens (D.Don) Endl.). Tanoak, a valuable food source to numerous wildlife species, is unlikely to successfully regenerate in diseased areas, and thus, affected redwood forests are transitioning to a novel state. In this study, to predict which species might replace tanoak, we investigated regeneration patterns in heavily impacted stands in Marin County, California. Our main findings were as follows: (i) despite reductions in canopy cover, there is no evidence that any species other than tanoak has exhibited a regenerative response to tanoak mortality, (ii) the regeneration stratum was dominated by redwood and tanoak (other tree species were patchy and (or) scarce), and (iii) some severely affected areas lacked sufficient regeneration to fully re-occupy available growing space. Our results indicate that redwood is likely to initially re-occupy the majority of the ground relinquished by tanoak, but also provide evidence that longer-term trajectories are unresolved, and may be highly responsive to management interventions.

scholarly journals Host Phenology and Leaf Effects on Susceptibility of California Bay Laurel to Phytophthora ramorum

2016 ◽  
Vol 106 (1) ◽  
pp. 47-55 ◽  
Author(s):  
Steven F. Johnston ◽  
Michael F. Cohen ◽  
Tamas Torok ◽  
Ross K. Meentemeyer ◽  
Nathan E. Rank
Keyword(s):  
Leaf Age ◽  
Spore Production ◽  
Phytophthora Ramorum ◽  
Sudden Oak Death ◽  
Forest Disease ◽  
Umbellularia Californica ◽  
Leaf Surfaces ◽  
Multiple Trees ◽  
The Relationship ◽  
Plant Susceptibility

Spread of the plant pathogen Phytophthora ramorum, causal agent of the forest disease sudden oak death, is driven by a few competent hosts that support spore production from foliar lesions. The relationship between traits of a principal foliar host, California bay laurel (Umbellularia californica), and susceptibility to P. ramorum infection were investigated with multiple P. ramorum isolates and leaves collected from multiple trees in leaf-droplet assays. We examined whether susceptibility varies with season, leaf age, or inoculum position. Bay laurel susceptibility was highest during spring and summer and lowest in winter. Older leaves (>1 year) were more susceptible than younger ones (8 to 11 months). Susceptibility was greater at leaf tips and edges than the middle of the leaf. Leaf surfaces wiped with 70% ethanol were more susceptible to P. ramorum infection than untreated leaf surfaces. Our results indicate that seasonal changes in susceptibility of U. californica significantly influence P. ramorum infection levels. Thus, in addition to environmental variables such as temperature and moisture, variability in host plant susceptibility contributes to disease establishment of P. ramorum.

Adam Zalužanský’s “De sexu plantarum” (1592): an early pioneering chapter on plant sexuality

2013 ◽  
Vol 40 (2) ◽  
pp. 244-256 ◽  
Author(s):  
Holger Funk
Keyword(s):  
Nineteenth Century ◽  
English Translation ◽  
History Of Botany ◽  
Main Work ◽  
Botanical History ◽  
History Of ◽  
The University ◽  
First Time

In the history of botany, Adam Zalužanský (d. 1613), a Bohemian physician, apothecary, botanist and professor at the University of Prague, is a little-known personality. Linnaeus's first biographers, for example, only knew Zalužanský from hearsay and suspected he was a native of Poland. This ignorance still pervades botanical history. Zalužanský is mentioned only peripherally or not at all. As late as the nineteenth century, a researcher would be unaware that Zalužanský’s main work Methodi herbariae libri tres actually existed in two editions from two different publishers (1592, Prague; 1604, Frankfurt). This paper introduces the life and work of Zalužanský. Special attention is paid to the chapter “De sexu plantarum” of Zalužanský’s Methodus, in which, more than one hundred years before the well-known De sexu plantarum epistola of R. J. Camerarius, the sexuality of plants is suggested. Additionally, for the first time, an English translation of Zalužanský’s chapter on plant sexuality is provided.

More Christian Apocrypha

2012 ◽  
Vol 41 (3) ◽  
pp. 16-21
Author(s):  
Tony Burke
Keyword(s):  
New Testament ◽  
Old Testament ◽  
North American ◽  
English Language ◽  
Primary Sources ◽  
University Of Edinburgh ◽  
The University ◽  
First Time ◽  
Medieval Christianity

Scholars interested in the Christian Apocrypha (CA) typically appeal to CA collections when in need of primary sources. But many of these collections limit themselves to material believed to have been written within the first to fourth centuries CE. As a result a large amount of non-canonical Christian texts important for the study of ancient and medieval Christianity have been neglected. The More Christian Apocrypha Project will address this neglect by providing a collection of new editions (some for the first time) of these texts for English readers. The project is inspired by the More Old Testament Pseudepigrapha Project headed by Richard Bauckham and Jim Davila from the University of Edinburgh. Like the MOTP, the MCAP is envisioned as a supplement to an earlier collection of texts—in this case J. K. Elliott’s The Apocryphal New Testament (Oxford 1991), the most recent English-language CA collection (but now almost two decades old). The texts to be included are either absent in Elliott or require significant revision. Many of the texts have scarcely been examined in over a century and are in dire need of new examination. One of the goals of the project is to spotlight the abilities and achievements of English (i.e., British and North American) scholars of the CA, so that English readers have access to material that has achieved some exposure in French, German, and Italian collections.

A University Education

2017 ◽  
Author(s):  
David Willetts
Keyword(s):  
Higher Education ◽  
Modern Society ◽  
University Education ◽  
Modern World ◽  
Controversial Issues ◽  
The Us ◽  
The Individual ◽  
The University ◽  
First Time ◽  
The Relationship

Universities have a crucial role in the modern world. In England, entrance to universities is by nation-wide competition which means English universities have an exceptional influence on schools--a striking theme of the book. This important book first investigates the university as an institution and then tracks the individual on their journey to and through university. In A University Education, David Willetts presents a compelling case for the ongoing importance of the university, both as one of the great institutions of modern society and as a transformational experience for the individual. The book also makes illuminating comparisons with higher education in other countries, especially the US and Germany. Drawing on his experience as UK Minister for Universities and Science from 2010 to 2014, the author offers a powerful account of the value of higher education and the case for more expansion. He covers controversial issues in which he was involved from access for disadvantaged students to the introduction of L9,000 fees. The final section addresses some of the big questions for the future, such as the the relationship between universities and business, especially in promoting innovation.. He argues that the two great contemporary trends of globalisation and technological innovation will both change the university significantly. This is an authoritative account of English universities setting them for the first time in their new legal and regulatory framework.

scholarly journals Introduction: Transdiasporic Rencontres in Việt Kiều Literature

2018 ◽  
Vol 15 (1-2) ◽  
pp. 1-5
Author(s):  
Alexandra Kurmann ◽  
Tess Do
Keyword(s):  
New Caledonia ◽  
Literary Texts ◽  
Special Issue ◽  
Contemporary Writing ◽  
The University ◽  
First Time ◽  
Vietnamese Diaspora

This special issue follows a conference entitled ‘Rencontres: A Gathering of Voices of the Vietnamese Diaspora’ that was held at the University of Melbourne, December 1-2 in 2016 and which sought to enable, for the first time, the titular transdiasporic rencontres or encounters between international authors of the Vietnamese diaspora. The present amalgam of previously unpublished texts written by celebrated Francophone and Anglophone authors of Vietnamese descent writing in France, New Caledonia and Australia today is the result of the intercultural exchanges that took place during that event. Literary texts by Linda Lê, Anna Moï and Thanh-Van Tran-Nhut are followed by writerly reflections on the theme of transdiasporic encounters from Hoai Huong Nguyen, Jean Vanmai and Hoa Pham. Framing and enriching these texts, scholarly contributions by established experts in the field consider the literary, cultural and linguistic transfers that characterize contemporary writing by authors of Vietnamese origin across the Francophone world. Ce volume spécial réunit les Actes du colloque ‘Rencontres : A Gathering of Voices of the Vietnamese Diaspora’ qui s’est tenue à l’Université de Melbourne les 1er et 2 décembre 2016 et qui visait à faciliter, pour la première fois, les rencontres entre les auteurs, chercheurs et universitaires internationaux de la diaspora vietnamienne. Les fruits de leurs échanges interculturels y sont réunis dans ce présent recueil sous deux formes complémentaires : d’un côté, les articles d’experts en littérature francophone comparée ; de l’autre, les contributions créatives de célèbres auteurs francophones et anglophones d’origine vietnamienne basés aujourd’hui en France, en Nouvelle Calédonie et en Australie. Les textes littéraires de Linda Lê, Anna Moï et Thanh-Van Tran-Nhut, suivis de réflexions d’auteurs par Hoai Huong Nguyen, Hoa Pham et Jean Vanmai sur le thème des rencontres transdiasporiques, se retrouvent enrichis par les études savantes menées sur les transferts littéraires, culturelles et linguistiques qui caractérisent l’écriture contemporaine des écrivains d’origine vietnamienne dans le monde francophone.

scholarly journals Bark traits, decomposition and flammability of Australian forest trees

2017 ◽  
Vol 65 (4) ◽  
pp. 327 ◽  
Author(s):  
Saskia Grootemaat ◽  
Ian J. Wright ◽  
Peter M. van Bodegom ◽  
Johannes H. C. Cornelissen ◽  
Veronica Shaw
Keyword(s):  
Forest Tree ◽  
Remarkable Feature ◽  
Interspecific Differences ◽  
Eucalypt Plantations ◽  
Physical Traits ◽  
Key Driver ◽  
Multiple Species ◽  
Species Specific ◽  
First Time ◽  
Different Tissues

Bark shedding is a remarkable feature of Australian trees, yet relatively little is known about interspecific differences in bark decomposability and flammability, or what chemical or physical traits drive variation in these properties. We measured the decomposition rate and flammability (ignitibility, sustainability and combustibility) of bark from 10 common forest tree species, and quantified correlations with potentially important traits. We compared our findings to those for leaf litter, asking whether the same traits drive flammability and decomposition in different tissues, and whether process rates are correlated across tissue types. Considerable variation in bark decomposability and flammability was found both within and across species. Bark decomposed more slowly than leaves, but in both tissues lignin concentration was a key driver. Bark took longer to ignite than leaves, and had longer mass-specific flame durations. Variation in flammability parameters was driven by different traits in the different tissues. Decomposability and flammability were each unrelated, when comparing between the different tissue types. For example, species with fast-decomposing leaves did not necessarily have fast-decomposing bark. For the first time, we show how patterns of variation in decomposability and flammability of bark diverge across multiple species. By taking species-specific bark traits into consideration there is potential to make better estimates of wildfire risks and carbon loss dynamics. This can lead to better informed management decisions for Australian forests, and eucalypt plantations, worldwide.

The Canons of John Mauropous

1947 ◽  
Vol 37 (1-2) ◽  
pp. 70-73 ◽  
Author(s):  
Joan Hussey
Keyword(s):  
Nineteenth Century ◽  
Sixteenth Century ◽  
Western Europe ◽  
Eleventh Century ◽  
Orthodox Church ◽  
Short Introduction ◽  
John Chrysostom ◽  
The University ◽  
First Time ◽  
Service Books

John Mauropous, an eleventh-century Metropolitan of Euchaïta, has long been commemorated in the service books of the Orthodox Church. The Synaxarion for the Office of Orthros on 30th January, the day dedicated to the Three Fathers, St. Basil the Great, St. Gregory the Theologian, and St. John Chrysostom, tells how the festival was instituted by Mauropous and describes him as ‘the well-known John, a man of great repute and well-versed in the learning of the Hellenes, as his writings show, and moreover one who has attained to the highest virtue’. In western Europe something was known of him certainly as early as the end of the sixteenth century; his iambic poems were published for the first time by an Englishman in 1610, and his ‘Vita S. Dorothei’ in the Acta Sanctorum in 1695. But it was not until the second half of the nineteenth century that scholars were really able to form some idea of the character and achievement of this Metropolitan of Euchaïta. Particularly important were two publications: Sathas' edition in 1876 of Michael Psellus' oration on John, and Paul de Lagarde's edition in 1882 of some of John's own writings. This last contained not only the works already printed, but a number of hitherto unpublished sermons and letters, together with the constitution of the Faculty of Law in the University of Constantinople, and a short introduction containing part of an etymological poem. But there remained, and still remains, one significant omission: John's canons have been almost consistently neglected.

scholarly journals Giovanni Aldini: From Animal Electricity to Human Brain Stimulation

2004 ◽  
Vol 31 (4) ◽  
pp. 576-584 ◽  
Author(s):  
André Parent
Keyword(s):  
Electric Current ◽  
Brain Stimulation ◽  
Experimental Physics ◽  
Influential Book ◽  
The University ◽  
Luigi Galvani ◽  
The 19Th Century ◽  
First Time ◽  
Deep Brain ◽  
Crucial Experiments

Two hundred years ago, Giovanni Aldini published a highly influential book that reported experiments in which the principles of Luigi Galvani (animal electricity) and Alessandro Volta (bimetallic electricity) were used together for the first time. Aldini was born in Bologna in 1762 and graduated in physics at the University of his native town in 1782. As nephew and assistant of Galvani, he actively participated in a series of crucial experiments with frog's muscles that led to the idea that electricity was the long-sought vital force coursing from brain to muscles. Aldini became professor of experimental physics at the University of Bologna in 1798. He traveled extensively throughout Europe, spending much time defending the concept of his discreet uncle against the incessant attacks of Volta, who did not believe in animal electricity. Aldini used Volta's bimetallic pile to apply electric current to dismembered bodies of animals and humans; these spectacular galvanic reanimation experiments made a strong and enduring impression on his contemporaries. Aldini also treated patients with personality disorders and reported complete rehabilitation following transcranial administration of electric current. Aldini's work laid the ground for the development of various forms of electrotherapy that were heavily used later in the 19th century. Even today, deep brain stimulation, a procedure currently employed to relieve patients with motor or behavioral disorders, owes much to Aldini and galvanism. In recognition of his merits, Aldini was made a knight of the Iron Crown and a councillor of state at Milan, where he died in 1834.

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