73 research outputs found
Melampsoridium hiratsukanum – invasive rust species in Lithuania, and its co-occurrence with eriophylid mite
An invasive East Asian rust fungus Melampsoridium hiratsukanum, obligate biotroph belonging to Pucciniastraceae, Pucciniales (Basidiomycota) is found widely spread on leaves of Alnus incana in eastern, central and southern parts of Lithuania. On Alnus glutinosa this fungus is rare, sometimes occurring with an alder leaf pest, a microscopic eriophyid gall mite Acalitus brevitarsus. Information on the distribution patterns, ecological and morphological characters of this neomycete is given
Species diversity and composition of fungal communities in a Scots pine forest affected by the great cormorant colony
A Scots pine forest, affected by the great cormorant colony, was studied by plot-based fungal survey method during the years 2010-2012 in Lithuania. Diversity and composition of fungal communities were investigated at five zones that had been influenced by different stages of breeding colony establishment: starting-point and almost abandoned cormorant colony part (zones A and B), active part (zones C and D), and the edge of the colony (zone E). The control zone G in undamaged by cormorants pine stand was assessed too. A total of 257 fungal species of ascomycetes including anamorphic fungi, basidiomycetes and zygomycetes were recorded. Seven species were registered for the first time in Lithuania. Species richness in the examined zones varied, lowest being in zones B (51 species), C (46) and D (73) and almost twice as high in the zones A and E (129 and 120, respectively). The comparison of fungal species compositions of different zones showed that their similarity was rather low (SS: 0.22–0.59). The most obvious changes in the trophic structure of fungal communities in the territory occupied by the bird colony were a strong decrease of mycorrhizal species, the presence of coprophilous fungi on forest litter, and the appearance of host-specialized fungi on alien and non-forest plants that have established in the disturbed forest
Diversity, migration routes, and worldwide population genetic structure of Lecanosticta acicola, the causal agent of brown spot needle blight
Lecanosticta acicola is a pine needle pathogen causing brown spot needle blight that results in premature needle shedding with considerable damage described in North America, Europe, and Asia. Microsatellite and mating type markers were used to study the population genetics, migration history, and reproduction mode of the pathogen, based on a collection of 650 isolates from 27 countries and 26 hosts across the range of L. acicola. The presence of L. acicola in Georgia was confirmed in this study. Migration analyses indicate there have been several introduction events from North America into Europe. However, some of the source populations still appear to remain unknown. The populations in Croatia and western Asia appear to originate from genetically similar populations in North America. Intercontinental movement of the pathogen was reflected in an identical haplotype occurring on two continents, in North America (Canada) and Europe (Germany). Several shared haplotypes between European populations further suggests more local pathogen movement between countries. Moreover, migration analyses indicate that the populations in northern Europe originate from more established populations in central Europe. Overall, the highest genetic diversity was observed in south-eastern USA. In Europe, the highest diversity was observed in France, where the presence of both known pathogen lineages was recorded. Less than half of the observed populations contained mating types in equal proportions. Although there is evidence of some sexual reproduction taking place, the pathogen spreads predominantly asexually and through anthropogenic activity
The increasing threat to European forests from the invasive foliar pine pathogen, Lecanosticta acicola
European forests are threatened by increasing numbers of invasive pests and pathogens. Over the past century, Lecanosticta acicola, a foliar pathogen predominantly of Pinus spp., has expanded its range globally, and is increasing in impact. Lecanosticta acicola causes brown spot needle blight, resulting in premature defoliation, reduced growth, and mortality in some hosts. Originating from southern regions of North American, it devastated forests in the USA's southern states in the early twentieth century, and in 1942 was discovered in Spain.Derived from Euphresco project 'Brownspotrisk,' this study aimed to establish the current distribution of Lecanosticta species, and assess the risks of L. acicola to European forests. Pathogen reports from the literature, and new/ unpublished survey data were combined into an open-access geo-database (http://www.portaloff orestpathology.com), and used to visualise the pathogen's range, infer its climatic tolerance, and update its host range. Lecanosticta species have now been recorded in 44 countries, mostly in the northern hemisphere. The type species, L. acicola, has increased its range in recent years, and is present in 24 out of the 26 European countries where data were available. Other species of Lecanosticta are largely restricted to Mexico and Central America, and recently Colombia.The geo-database records demonstrate that L. acicola tolerates a wide range of climates across the northern hemisphere, and indicate its potential to colonise Pinus spp. forests across large swathes of the Europe. Pre-liminary analyses suggest L. acicola could affect 62% of global Pinus species area by the end of this century, under climate change predictions.Although its host range appears slightly narrower than the similar Dothistroma species, Lecanosticta species were recorded on 70 host taxa, mostly Pinus spp., but including, Cedrus and Picea spp. Twenty-three, including species of critical ecological, environmental and economic significance in Europe, are highly susceptible to L. acicola, suffering heavy defoliation and sometimes mortality. Variation in apparent susceptibility between reports could reflect variation between regions in the hosts' genetic make-up, but could also reflect the signif-icant variation in L. acicola populations and lineages found across Europe. This study served to highlight sig-nificant gaps in our understanding of the pathogen's behaviour.Lecanosticta acicola has recently been downgraded from an A1 quarantine pest to a regulated non quarantine pathogen, and is now widely distributed across Europe. With a need to consider disease management, this study also explored global BSNB strategies, and used Case Studies to summarise the tactics employed to date in Europe
Potential Interactions between Invasive Fusarium circinatum and Other Pine Pathogens in Europe
Potential interactions between invasive Fusarium circinatum and other pine pathogens in Europe
Global Geographic Distribution and Host Range of Fusarium circinatum, the Causal Agent of Pine Pitch Canker
Funding: This study was financially supported by COST Action FP1406 (PINESTRENGTH), the Estonian Science Foundation grant PSG136, the Forestry Commission, United Kingdom, the Phytophthora Research Centre Reg. No. CZ.02.1.01/0.0/0.0/15_003/0000453, a project co-financed by the European Regional Development Fund. ANSES is supported by a grant managed by the French National Research Agency (ANR) as part of the “Investissements d’Avenir” programme (ANR-11-LABX-0002-01, Laboratory of ExcellenceARBRE). SW was partly supported by BBSRC Grant reference BB/L012251/1 “Promoting resilience of UK tree species to novel pests & pathogens: ecological & evolutionary solutions (PROTREE)” jointly funded by BBSRC, Defra, ESRC, the Forestry Commission, NERC and the Scottish Government, under the Tree Health and Plant Biosecurity Initiative. Annual surveys in Switzerland were financially supported by the Swiss Federal Office for the Environment FOEN. Acknowledgments: Andrea Kunova and Cristina Pizzatti are acknowledged for the assistance in the sampling. Thanks are due to Dina Ribeiro and Helena Marques from ICNF-Portuguese Forest Authority for providing location coordinates. We thank three anonymous reviwers for valuable corrections and suggestions.Peer reviewedPublisher PD
Global Geographic Distribution and Host Range of Fusarium circinatum, the Causal Agent of Pine Pitch Canker
Fusarium circinatum, the causal agent of pine pitch canker (PPC), is currently one of the most important threats of Pinus spp. globally. This pathogen is known in many pine-growing regions, including natural and planted forests, and can affect all life stages of trees, from emerging seedlings to mature trees. Despite the importance of PPC, the global distribution of F. circinatum is poorly documented, and this problem is also true of the hosts within countries that are affected. The aim of this study was to review the global distribution of F. circinatum, with a particular focus on Europe. We considered (1) the current and historical pathogen records, both positive and negative, based on confirmed reports from Europe and globally; (2) the genetic diversity and population structure of the pathogen; (3) the current distribution of PPC in Europe, comparing published models of predicted disease distribution; and (4) host susceptibility by reviewing literature and generating a comprehensive list of known hosts for the fungus. These data were collated from 41 countries and used to compile a specially constructed geo-database. A review of 6297 observation records showed that F. circinatum and the symptoms it causes on conifers occurred in 14 countries, including four in Europe, and is absent in 28 countries. Field observations and experimental data from 138 host species revealed 106 susceptible host species including 85 Pinus species, 6 non-pine tree species and 15 grass and herb species. Our data confirm that susceptibility to F. circinatum varies between different host species, tree ages and environmental characteristics. Knowledge on the geographic distribution, host range and the relative susceptibility of different hosts is essential for disease management, mitigation and containment strategies. The findings reported in this review will support countries that are currently free of F. circinatum in implementing effective procedures and restrictions and prevent further spread of the pathogen
Molecular taxonomy of bambusicolous fungi: Tetraplosphaeriaceae, a new pleosporalean family with Tetraploa-like anamorphs
A new pleosporalean family Tetraplosphaeriaceae is established to
accommodate five new genera; 1) Tetraplosphaeria with small ascomata
and anamorphs belonging to Tetraploa s. str., 2)
Triplosphaeria characterised by hemispherical ascomata with rim-like
side walls and anamorphs similar to Tetraploa but with three conidial
setose appendages, 3) Polyplosphaeria with large ascomata surrounded
by brown hyphae and anamorphs producing globose conidia with several setose
appendages, 4) Pseudotetraploa, an anamorphic genus, having
obpyriform conidia with pseudosepta and four to eight setose appendages, and
5) Quadricrura, an anamorphic genus, having globose conidia with one
or two long setose appendages at the apex and four to five short setose
appendages at the base. Fifteen new taxa in these genera mostly collected from
bamboo are described and illustrated. They are linked by their Tetraploa
s. l. anamorphs. To infer phylogenetic placement in the
Pleosporales, analyses based on a combined dataset of small- and
large-subunit nuclear ribosomal DNA (SSU+LSU nrDNA) was carried out.
Tetraplosphaeriaceae, however, is basal to the main pleosporalean
clade and therefore its relationship with other existing families was not
completely resolved. To evaluate the validity of each taxon and to clarify the
phylogenetic relationships within this family, further analyses using
sequences from ITS-5.8S nrDNA (ITS), transcription elongation factor 1-α
(TEF), and β-tubulin (BT), were also conducted. Monophyly of the family
and that of each genus were strongly supported by analyses based on a combined
dataset of the three regions (ITS+TEF+BT). Our results also suggest that
Tetraplosphaeria (anamorph: Tetraploa s. str.) is an
ancestral lineage within this family. Taxonomic placement of the bambusicolous
fungi in Astrosphaeriella, Kalmusia, Katumotoa, Massarina,
Ophiosphaerella, Phaeosphaeria, Roussoella, Roussoellopsis, and
Versicolorisporium, are also discussed based on the SSU+LSU
phylogeny
Cross-national variations in reported discrimination among people treated for major depression worldwide: The ASPEN/INDIGO international study
Background: No study has so far explored differences in discrimination reported by people with major depressive disorder (MDD) across countries and cultures. Aims: To (a) compare reported discrimination across different countries, and (b) explore the relative weight of individual and contextual factors in explaining levels of reported discrimination in people with MDD. Method: Cross-sectional multisite international survey (34 countries worldwide) of 1082 people with MDD. Experienced and anticipated discrimination were assessed by the Discrimination and Stigma Scale (DISC). Countries were classified according to their rating on the Human Development Index (HDI). Multilevel negative binomial and Poisson models were used. Results: People living in 'very high HDI' countries reported higher discrimination than those in 'medium/low HDI' countries. Variation in reported discrimination across countries was only partially explained by individual-level variables. The contribution of country-level variables was significant for anticipated discrimination only. Conclusions: Contextual factors play an important role in anticipated discrimination. Country-specific interventions should be implemented to prevent discrimination towards people with MDD
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