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Lophodermium piceae represents the most common Norway spruce needle endophyte. The aim of this study was to find out whether subpopulations of L. piceae in climatically different environments (in which Norway spruce occurs natively) are adapted to local thermal conditions. L. piceae's ability for thermal adaptation was investigated by determining growth rates of 163 isolates in vitro at four different temperatures: 2, 6, 20 and 25 °C. Isolates were obtained between 1995 and 2010 from apparently healthy needles sampled in Finland, Poland, Switzerland, Italy and southeastern Siberia. The sampling sites represent seven climatically distinct locations. Results were evaluated in relation to the age and geographic origin of the isolate, in addition to the highest and lowest average monthly temperature of the sampling location. We found a significant correlation between the growth rate and the age of the isolate at 25 °C. Variation in growth rates between subpopulations was low compared to within subpopulations. Only at 2 °C did statistically significant differences between the average growth rates of subpopulations emerge. These results suggest that L. piceae covers the whole distribution area of Norway spruce but that generally the thermal reaction norm of its subpopulations has not changed according to local temperature ranges, despite high contrast in thermal conditions across this vast area. Therefore, it would appear that the thermal environment is not a crucial factor in assessing the fitness of this fungal species within the native range of Norway spruce., (Copyright © 2019 British Mycological Society. Published by Elsevier Ltd. All rights reserved.)

Euonymus japonicus Thunb. is a woody and ornamental plant popular in China, Europe and North America. Powdery mildew is one of the most serious diseases that affect E. japonicus growth. In this study, the diseased and apparently healthy leaves were collected from E. japonicus planted in a greenbelt in Beijing, and the effect of powdery mildew on the epiphytic microbial community was investigated by using Illumina sequencing. The results showed that the healthy leaves (HL) harbored greater bacterial and fungal diversity than diseased leaves (DL). Furthermore, both bacterial and fungal communities in DL exhibited significantly different structures from those in HL. The relative abundance of several bacterial phyla (Proteobacteria and Firmicutes) and fungal phyla (Ascomycota and Basidiomycota) were altered by powdery mildew. At the genus level, most genera decreased as powdery mildew pathogen Erysiphe increased, while the genera Kocuria and Exiguobacterium markedly increased. Leaf properties, especially protein content was found to significantly affect beta-diversity of the bacterial and fungal community. Network analysis revealed that positive bacterial interactions in DL were stronger than those in HL samples. Insights into the underlying the indigenous microbial phyllosphere populations of E. japonicus response to powdery mildew will help in the development of methods for controlling plant diseases.

Changes in the mode of reproduction are frequently observed in invasive fungal populations. The ascomycete Cryphonectria parasitica, which causes Chestnut Blight, was introduced to Europe from North America and Asia in the 20th century. Previous genotyping studies based on ten microsatellite markers have identified several clonal lineages which have spread throughout western Europe, suggesting that asexuality was the main reproductive mode of this species during colonization, although occasional sexual reproduction is not excluded. Based on the whole-genome sequences alignment of 46 C. parasitica isolates from France, North America and Asia, genealogy and population structure analyses mostly confirmed these lineages as clonal. However, one of these clonal lineages showed a signal of strong recombination, suggesting different strategies of reproduction in western Europe. Signatures of several recent recombination events within all the French clonal lineages studied here were also identified, indicating that gene flow is regular between these lineages. In addition, haplotype identification of seven French clonal lineages revealed that emergences of new clonal lineages during colonization were the result of hybridization between the main expanding clonal lineages and minor haplotypes non-sequenced in the present study. This whole-genome sequencing study underlines the importance of recombination events in the invasive success of these clonal populations, and suggests that sexual reproduction may be more frequent within and between the western European clonal lineages of C. parasitica than previously assumed using few genetic markers., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Background: Bat flies (Diptera: Nycteribiidae and Streblidae) are obligate, blood-sucking ectoparasites of bats with specialized morphology, life-cycle and ecology. Bat flies are occasionally infected by different species of Laboulbeniales (Fungi: Ascomycota), microscopic fungal ectoparasites belonging to three genera: Arthrorynchus spp. are restricted to the Eastern Hemisphere, while species of Gloeandromyces and Nycteromyces occur on Neotropical bat flies. Little is known about the distribution and host specificity of Arthrorynchus spp. on bat flies. In this study, we focused on sampling bat flies from the cave-dwelling bat species Miniopterus schreibersii. Bat and ectoparasite collection took place in Albania, Croatia, Hungary, Italy, Portugal, Slovakia, Spain and Switzerland. Flies were inspected for Laboulbeniales infections., Results: Six hundred sixty seven bat flies of five species were collected: Nycteribia latreillii, N. pedicularia, N. schmidlii, Penicillidia conspicua, and P. dufourii. Laboulbeniales infection was observed on 60 specimens (prevalence = 9%). Two Laboulbeniales species, Arthrorhynchus eucampsipodae and A. nycteribiae, were present on three bat fly species. All observations of A. eucampsipodae were on N. schmidlii, and A. nycteribiae was present on P. conspicua and P dufourii. Arthrorhynchus eucampsipodae is, for the first time, reported from Slovakia and Spain. Arthrorhynchus nycteribiae represents a new country record for Portugal and Slovakia. There were no significant differences among infection rates in different countries. Females of N. schmidlii showed a higher infection rate than males with an observable trend (P = 0.0502). No sex differences in infection rate for P. conspicua and P. dufourii were detected. Finally, thallus density was significantly lower in N. schmidlii compared to P. conspicua and P. dufourii., Conclusions: With this study, we contribute to the knowledge of the geographical distribution and host specificity of Laboulbeniales fungi associated with ectoparasitic bat flies within Europe. We discuss parasite prevalence and host specificity in the light of our findings and the available literature. Penicillidia conspicua is unambiguously the main host species for A. nycteribiae based on our and previous findings. Differences in parasite intensity and sex-biased infections of the fungi are possible depending on the species.

Ash dieback is caused by an invasive pathogen Hymenoscyphus fraxineus, which emerged in Europe in the 1990s and jeopardizes the management of ash stands. Although the biological cycle of the pathogen is well understood, its dispersal patterns via airborne spores remain poorly described. We investigated the seasonal and spatial patterns of dispersal in France using both a passive spore-trapping method coupled with a real-time PCR assay and reports of ash dieback based on symptom observations. Spores detection varies from year to year with a detection ability of 30-47% depending on meteorological conditions, which affect both production of inoculum and efficiency of the trapping. Nevertheless, our results are consistent and we showed that the sporulation peak occurred from June to August and that spores were detected up to 50-100 km ahead of the disease front, proving the presence of the pathogen before any observation of symptoms. The spore dispersal gradient was steep, most of inoculum remaining within 50 m of infected ashes. Two dispersal kernels were fitted using Bayesian methods to estimate the mean dispersal distance of H. fraxineus from inoculum sources. The estimated mean distances of dispersal, either local or regional scale, were 1.4 km and 2.6 km, respectively, the best fitting kernel being the inverse power-law. This information may help to design disease management strategies.

The ascomycetous fungus Cryphonectria parasitica (Murr.) is one of the most important fungal pathogens of chestnut (Castanea sativa Mill.), causing chestnut blight. It is originated from Eastern Asia and was introduced into North America, and later into Europe. Almost 100 C. parasitica isolates were collected mainly from the Carpathian Basin to study their diversity and phylogenetic relationships. Three nuclear molecular markers were tested: (i) internal transcribed spacers (ITS), (ii) translation elongation factor 1 subunit alpha (tef1), and (iii) six microsatellite loci. The ITS region proved to be highly polymorphic but this kind of variability did not reflect the geographical regions of the isolates, while the tef1 sequences were identical in all isolates. Microsatellite haplotype diversity was relatively high (0.923-0.984) calculated for the fungal populations of the Carpathian Basin. This may have resulted from the multiple introductions from diverse origins of the populations, close to the first site of observation in Northern Italy. The BAPS analysis of the microsatellite markers occasionally grouped together samples from remote geographical origin, suggesting human assistance in the introduction of new C. parasitica haplotypes from distinct areas.

Stemphylium vesicarium is the causal agent of brown spot of pear, an important disease reported in pear-growing areas of Europe. The pathogen is able to colonize pear leaf debris and dead tissues of herbaceous plants and produce abundant ascospores and conidia that are capable of infecting pear trees. Inoculum monitoring in pear orchards is mainly achieved through spore traps and species identification is based on conidial morphology, but the similarities on conidial traits among species of Stemphylium make correct identification difficult. In this work a total of thirty-seven Stemphylium isolates from pear orchards were characterized at the morphological, pathogenic, and molecular level. Correspondence among ITS and gpd sequences and morphological traits were evaluated. Species identification based exclusively on morphological data was not feasible. Combined morphological and molecular data were necessary for unambiguous identification of isolates in the S. vesicarium species group. Only isolates identified as S. vesicarium were pathogenic on pear. The study revealed that several species of Stemphylium coexist in pear orchards with S. vesicarium, the causal agent of BSP, and that combined morphological and molecular data are needed to differentiate them. Consequently, direct measurements of the airborne inoculum using volumetric spore traps may overestimate the actual pathogen population., (Copyright © 2014 The British Mycological Society. Published by Elsevier Ltd. All rights reserved.)

The population genetics of the family Partitiviridae was studied within the European race of the conifer pathogen Gremmeniella abietina. One hundred sixty-two isolates were collected from different countries, including Canada, the Czech Republic, Finland, Italy, Montenegro, Serbia, Spain, Switzerland, Turkey and the United States. A unique species of G. abietina RNA virus-MS1 (GaRV-MS1) appears to occur indistinctly in G. abietina biotypes A and B, without a particular geographical distribution pattern. Forty-six isolates were shown to host GaRV-MS1 according to direct specific RT-PCR screening, and the virus was more common in biotype A than B. Phylogenetic analysis based on 46 partial coat protein (CP) cDNA sequences divided the GaRV-MS1 population into two closely related clades, while RNA-dependent RNA polymerase (RdRp) sequences revealed only one clade. The evolution of the virus appears to mainly occur through purifying selection but also through recombination. Recombination events were detected within alignments of the three complete CP and RdRp sequences of GaRV-MS1. This is the first time that recombination events have been directly identified in fungal partitiviruses and in G. abietina in particular. The results suggest that the population dynamics of GaRV-MS1 do not have a direct impact on the genetic structure of its host, G. abietina, though they might have had an innocuous ancestral relationship., (Copyright © 2014 The British Mycological Society. Published by Elsevier Ltd. All rights reserved.)

Applying early names, with or without original material, to genealogical species is challenging. For morels this task is especially difficult because of high morphological stasis and high plasticity of apothecium color and shape. Here we propose a nomenclatural revision of true morels (Morchella, Pezizales) from Europe and North America, based on molecular phylogenetic analyses of portions of the genes for RNA polymerase II largest subunit (RPB1) and second largest subunit (RPB2), translation elongation factor-1α (TEF1), the nuc rDNA region encompassing the internal transcribed spacers 1 and 2, along with the 5.8S rDNA (ITS), and partial nuc 28S rDNA D1-D2 domains (28S). The 107 newly sequenced collections were from both continents, including 48 types, together with previously published sequences. Names are applied to 30 of the 65 currently recognized genealogical species. Results of the present study revealed that the number of Morchella species in Europe (n = 21) is nearly identical to that in North America (n = 22). Only seven species were found on both continents, consistent with previous reports of high continental endemism within the genus. Presently it is not possible to tell whether the transoceanic disjunctions were due to human activities, migration across a Bering land bridge or long-distance dispersal. In an effort to stabilize the taxonomy, due in part to the recent publication of synonyms for 11 of the species, accepted names are presented together with their corresponding later synonyms. A new subclade that includes holotypes of M. castanea and M. brunneorosea is identified in sect. Morchella (Esculenta Clade). Lectotypes for Morchella deliciosa, M. eximia and M. tridentina are designated here, as well as epitypes for M. dunalii, M. eximia, M. purpurascens and M. vulgaris. Morchella conica was determined to be illegitimate, and further research is required to determine the identity of M. elata and M. inamoena., (© 2015 by The Mycological Society of America.)

This study reports a case of a 56-year-old white male, retired coal-miner, diagnosed with chromoblastomycosis lasting 20 years. The infection site was the burnt skin of the back. For many years the patient had not undertaken any treatment believing that the lesion had been a burn scar. A gradual increase in lesion size prompted the patient to start therapy. The diagnosis was made by histopathological examination and mycological culture. Identification of the causative agent at the species level was achieved by sequence analysis of the internal transcribed spacer (ITS) region and D1/D2 domains of the 26S rDNA. To our knowledge, this is the first documented case of chromoblastomycosis caused by Fonsecaea monophora in temperate Europe, outside the endemic area for the disease. This finding is highly significant for understanding the routes of infection of chromoblastomycosis and radically revises the traditional view of the natural ecology of the etiological agents of the disease.

We studied the bee specialist fungus Ascosphaera in wild solitary bees to investigate the diversity of the genus in nature and the ecology of these fungi with their bee hosts. A new morphologically distinctive species was discovered which also has a unique nrITS sequence. This new species, here named Ascosphaera callicarpa, is common on the larval feces of the solitary bee Chelostoma florisomne which nests in the Phragmites reeds of thatched roofs in Europe. Because collections of Ascosphaera from wild bees are scarce and because little is known about the ecology and distribution of the majority of the species in the genus, a key to the species thus far reported for Europe is included.

Based on morphology, fungal species have been considered widespread and as a result names of species from Europe or eastern North America were applied to species in western North America. However, DNA sequences have shown that many western taxa are different from their European counterparts; one such case is presented here. Comparisons of ITS and LSU rDNA sequences from ectomycorrhizal root tips and ascomata of specimens identified as Helvella lacunosa from North America, Europe and Asia revealed that the taxa from western North America and Mexico formed a well supported clade different from the eastern North American, European and Asian taxa. Within this western North American clade there are at least four taxa. Here we describe two of these western taxa as new species: Helvella vespertina and Helvella dryophila. Helvella vespertina is a bigger version of H. lacunosa, is variable in hymenial color and shape and forms ectomycorrhizae with conifers; it fruits typically Oct-Jan. Helvella dryophila is characterized by a dark almost black, squat pileus, a light stipe when young, medium size and forms ectomycorrhizae with Quercus species; it fruits Jan-Jun. Due to insufficient material, the two other Helvella taxa are discussed but not formally described here. We also examined the Hypomyces and other mycoparasites associated with the ascomata of Helvella species and discuss misleadingly labeled sequences in public databases.

The genetic structure of the genus Mitovirus community hosted by the European pathogenic conifer fungus Gremmeniella abietina var. abietina was investigated. Gremmeniella abietina is a species complex with a divergent mycovirus community, composed mainly of Totivirus, Partitivirus, and Mitovirus species. In this work, the total doubled-stranded (ds)RNA from 353 isolates from Canada, Finland, Spain, Switzerland, Turkey, and USA was extracted to look for the presence of a ca. 2.5 kb band typical of mitoviruses' genomes. Based on the banding data, 60 partial RNA-dependent RNA polymerase (RdRp) DNA sequences (ca. 500 bp) were amplified with reverse transcription-polymerase chain reaction (RT-PCR) and sequenced. Two distantly related mitovirus groups (species) were observed in the clustering analysis, one of them related to GMV1-1 and the other one related to a new putative species described in this study, GMV2-1. Viruses in these two clusters seemed to be subjected to purifying selection. The cluster with GMV1-1 included viruses observed in the Finnish biotype A and Spanish strains, whereas the cluster including GMV2-1 was composed of viruses of the Finnish biotype B and one from the Spanish population. Thereby, the Spanish population of G. abietina harboured mitovirus strains occurring in both biotype A and B strains, and it is the first one hosting distantly related mycoviruses of a single genus in one population of G. abietina. This may suggest that horizontal transmission of viruses could have occurred between biotype B and the Spanish population., (Copyright © 2012 The British Mycological Society. Published by Elsevier Ltd. All rights reserved.)

White-nose syndrome (WNS) is an emerging disease of hibernating bats associated with cutaneous infection by the fungus Geomyces destructans (Gd), and responsible for devastating declines of bat populations in eastern North America. Affected bats appear emaciated and one hypothesis is that they spend too much time out of torpor during hibernation, depleting vital fat reserves required to survive the winter. The fungus has also been found at low levels on bats throughout Europe but without mass mortality. This finding suggests that Gd is either native to both continents but has been rendered more pathogenic in North America by mutation or environmental change, or that it recently arrived in North America as an invader from Europe. Thus, a causal link between Gd and mortality has not been established and the reason for its high pathogenicity in North America is unknown. Here we show that experimental inoculation with either North American or European isolates of Gd causes WNS and mortality in the North American bat, Myotis lucifugus. In contrast to control bats, individuals inoculated with either isolate of Gd developed cutaneous infections diagnostic of WNS, exhibited a progressive increase in the frequency of arousals from torpor during hibernation, and were emaciated after 3-4 mo. Our results demonstrate that altered torpor-arousal cycles underlie mortality from WNS and provide direct evidence that Gd is a novel pathogen to North America from Europe.

White-nose syndrome, associated with the fungal skin infection geomycosis, caused regional population collapse in bats in North America. Our results, based on histopathology, show the presence of white-nose syndrome in Europe. Dermatohistopathology on two bats (Myotis myotis) found dead in March 2010 with geomycosis in the Czech Republic had characteristics resembling Geomyces destructans infection in bats confirmed with white-nose syndrome in US hibernacula. In addition, a live M. myotis, biopsied for histopathology during hibernation in April 2011, had typical fungal infection with cupping erosion and invasion of muzzle skin diagnostic for white-nose syndrome and conidiospores identical to G. destructans that were genetically confirmed as G. destructans.

Throughout the world, epidemiological studies were established to examine the relationship between air pollution and mortality rates and adverse respiratory health effects. However, despite the years of discussion the correlation between adverse health effects and atmospheric pollution remains controversial, partly because these studies are frequently restricted to small and well-monitored areas. Monitoring air pollution is complex due to the large spatial and temporal variations of pollution phenomena, the high costs of recording instruments, and the low sampling density of a purely instrumental approach. Therefore, together with the traditional instrumental monitoring, bioindication techniques allow for the mapping of pollution effects over wide areas with a high sampling density. In this study, instrumental and biomonitoring techniques were integrated to support an epidemiological study that will be developed in an industrial area located in Gijon in the coastal of central Asturias, Spain. Three main objectives were proposed to (i) analyze temporal patterns of PM₁₀ concentrations in order to apportion emissions sources, (ii) investigate spatial patterns of lichen conductivity to identify the impact of the studied industrial area in air quality, and (iii) establish relationships amongst lichen conductivity with some site-specific characteristics. Samples of the epiphytic lichen Parmelia sulcata were transplanted in a grid of 18 by 20 km with an industrial area in the center. Lichens were exposed for a 5-mo period starting in April 2010. After exposure, lichen samples were soaked in 18-MΩ water aimed at determination of water electrical conductivity and, consequently, lichen vitality and cell damage. A marked decreasing gradient of lichens conductivity relative to distance from the emitting sources was observed. Transplants from a sampling site proximal to the industrial area reached values 10-fold higher than levels far from it. This finding showed that lichens reacted physiologically in the polluted industrial area as evidenced by increased conductivity correlated to contamination level. The integration of temporal PM₁₀ measurements and analysis of wind direction corroborated the importance of this industrialized region for air quality measurements and identified the relevance of traffic for the urban area.

Genetic structure of the European Gremmeniella abietina var. abietina was analyzed in this study. Ninety-two Spanish isolates, six Swiss isolates of Alpine biotype, 76 Finnish isolates of biotype A and 54 Finnish and seven Russian isolates of biotype B were collected. Genetic variation of different populations was analyzed using sequence analysis of specifically amplified markers GAAA1000, GAAA800 and ACA900. Variation in the GAAA1000 marker was significant, and composed of 33 alleles divided into the following four studied populations: five alleles in the Alpine type, 12 in biotype B, 16 in biotype A and two in the Spanish population. Based on variation in GAAA1000 marker, a subset of isolates were further analyzed using GAAA800 and ACA900 sequences, which showed lower overall genetic variability, and no variation among the Spanish population. Genetic differentiation analysis revealed a high genetic differentiation among populations. Finally, clustering analysis of GAAA1000 sequences showed that the Spanish isolates clearly separated from the rest of the biotypes, whereas the Alpine type was closely related to the B type. However, one of the A-type isolates had an identical GAAA1000 allele with the prevailing allele among Spanish isolates. Altogether, our data suggest that the Spanish population is genetically highly differentiated from any other G. abietina population in Europe with a probable A-type origin., (Copyright © 2010 The British Mycological Society. Published by Elsevier Ltd. All rights reserved.)

White-nose syndrome is an emerging disease in North America that has caused substantial declines in hibernating bats. A recently identified fungus (Geomyces destructans) causes skin lesions that are characteristic of this disease. Typical signs of this infection were not observed in bats in North America before white-nose syndrome was detected. However, unconfirmed reports from Europe indicated white fungal growth on hibernating bats without associated deaths. To investigate these differences, hibernating bats were sampled in Germany, Switzerland, and Hungary to determine whether G. destructans is present in Europe. Microscopic observations, fungal culture, and genetic analyses of 43 samples from 23 bats indicated that 21 bats of 5 species in 3 countries were colonized by G. destructans. We hypothesize that G. destructans is present throughout Europe and that bats in Europe may be more immunologically or behaviorally resistant to G. destructans than their congeners in North America because they potentially coevolved with the fungus.

Ramularia collo-cygni is now recognized as an important pathogen of barley in Northern Europe and New Zealand. It induces necrotic spotting and premature leaf senescence, leading to loss of green leaf area in crops, and can result in substantial yield losses. The fungus produces a number of anthraquinone toxins called rubellins, which act as host nonspecific toxins with photodynamic activity. These toxins induce lipid peroxidation and are possibly the cause of the chlorosis and necrosis observed in leaves infected with R. collo-cygni. The fact that the fungus can remain latent in barley plants until flowering, coupled with its very slow growth in vitro, makes it difficult to detect in crops. As a result, the epidemiology of this pathogen remains poorly understood. However, the recent development of rapid and reliable PCR methods for specific detection of R. collo-cygni offers the prospect of increased understanding of its epidemiology and improved disease control.

Cenococcum geophilum is perhaps the most widely distributed and most recognized ectomycorrhizal fungus with a host range of more than 200 tree species from 40 genera of both angiosperms and gymnosperms. We conducted a phylogenetic analysis on a large collection of isolates (n=74) from North America and Europe based on glyceraldehyde 3-phosphate dehydrogenase (gpd). A subset of isolates (n=22) also was analyzed with the more conservative LSU-rDNA locus. Significant nucleotide diversity was detected (approximately 20%) in the gpd region and the LSU-rDNA analysis supported that the C. geophilum isolates studied were monophyletic but distinct from two isolates, Am5-1 and N2-10, which previously were used in population genetic studies of this species. These results suggest that Am5-1 and N2-10 are likely two undescribed species or even genera. Our results suggest that C. geophilum sensu lato is a species complex and support previous molecular, physiological and morphological studies that have shown significant diversity in C. geophilum. This study also revealed that caution is advised when conducting population genetic studies in C. geophilum due to the possibility of pooling unrelated isolates. This potential problem also has implications for other fungal taxa because cryptic species routinely have been found in recent years based on molecular data.

Diaporthe helianthi is the causal agent of sunflower stem canker, a serious pathogen of sunflower in Europe, which has been sporadically recorded in Italy. A collection of 26 Diaporthe helianthi isolates deriving from different geographic origins was analysed in order to determine the presence of extra-chromosomal genetic determinants and their molecular diversity. Extra-chromosomal bands in total genomic DNAs were identified in every French and the Yugoslavian isolate and in only one Italian isolate, while no Romanian and Argentinean isolates resulted to host any plasmids. When tested for their chemicophysical nature, they were recognised as linear plasmids sized about 2.3 Kb. A more detailed analysis was performed on a plasmid purified from a French isolate (plasmid F). Its intracellular localisation resulted as mitochondrial. Plasmid F was also exploited as a probe in Southern hybridisation experiments, in which it recognised only plasmids present in the genomes of French and Yugoslavian isolates (countries were the disease has a heavy incidence) indicating a strong correlation to geographic origin. An RFLP hybridisation analysis performed on genomic DNAs revealed a homogeneous restriction pattern in all French and Yugoslavian isolates, suggesting molecular homology among plasmids present in those isolates.

Molecular and genetic approaches were used to evaluate the genetic relatedness among isolates of the fungus Phoma macrostoma Montagne originating from Canada and Europe and to other species in the genus Phoma. Distinct differences were observed in genetic variation among nine species of the genus Phoma. Randomly amplified polymorphic DNA (RAPD) revealed the presence of intraspecific genetic variation among the isolates of P. macrostoma, with the isolates being used for biological weed control being distributed in a distinct phylogenetic cluster. Additional variation within the biocontrol isolate cluster in P. macrostoma was revealed by pulsed field gel electrophoresis (PFGE), which showed that biocontrol isolates generated two different chromosomal profiles, however the profiles did not relate to their Canadian ecozone origin. Mating studies showed that biocontrol isolates of P. macrostoma from Canada did not produce sexual reproductive structures and were incapable of crossing. These studies also confirmed that no obvious differentiation exists among the biocontrol isolates of P. macrostoma from Canadian Ecozones 3 and 4.

A fossil ascomycete was found attached to the thorax of a stalk eyed fly (Diopsidae: Prosphyracephala succini) in a fragment of Baltic amber. The fungus is assigned to the extant genus Stigmatomyces and described as S. succini sp. nov. This find is the first fossil record of the order Laboulbeniales. At the same time it constitutes the oldest record of a parasitic fungus on an insect. The palaeohabitat is discussed with regard to the find.

Entoleuca mammata (syn. Hypoxylon mammatum) is a damaging pathogen of Populus tremuloides and P. grandidentata in North America and P. tremula in Europe, where the fungus occurs only sporadically in alpine regions and Scandinavia. It has been hypothesized that E. mammata was introduced to Europe from North America. In this study, E. mammata isolates collected from Europe and North America were compared by a sequence analysis of two DNA markers derived from DNA fingerprints. The objective of the study was to elucidate the relationship between North American and European E. mammata populations by testing two hypotheses: (1) North American and European isolates are conspecific; and (2) the fungus was introduced between continents causing both a founder effect and a genetic bottleneck. North American populations were found to be more polymorphic, but no major phylogenetic differences between fungal isolates collected from different continents were found. This result combined with the historical observations of the disease in Europe implies that E. mammata was introduced to Europe several centuries ago.

DNA sequence data from three nuclear loci were collected from 384 isolates representing fourteen globally distributed populations of the plant pathogenic fungus Mycosphaerella graminicola. Gene genealogies were constructed for the actin and beta-tubulin loci as well as for the previously characterized RFLP locus STS2. The STS2 and beta-tubulin loci showed greater potential for phylogenetic studies than the actin locus. Greater sequence diversity was found in the "Old World" populations (Middle East and Europe) than in the "New World" populations (North and South America and Australia). The gene trees were rooted using homologous DNA sequences of Septoria passerinii, the closest known relative to M. graminicola, as well as coalescent rooting. Based on the rooted trees, a tentative phylogenetic history of these populations was inferred. The Middle East appears to be the most likely center of origin, while European populations are more ancient than New World populations. A test for neutrality indicated that the intron in the actin locus could be under selection, while the other two sequence loci were neutral.

Samples of a carbonated orange drink, raw materials, and intermediate products originating from 6 Iraqi bottling plants were examined. 69 drinks, 4 flavoured syrups and 19 simple syrups contained yeasts, whereas all samples from one plant and all samples of beverage base were free from viable yeasts. From the orange drink 2 species were isolated viz. Saccharomyces montanus and Torulopsis stellata. The following species were present in simple syrup: Hansenula anomala, Sacch. bisporus var. mellis, T. candida and T. stellata. Sacch. bisporus var. mellis was also isolated from favoured syrup. Representative strains were submitted to routine growth tests at reduced oxygen tension, at reduced water activity and on solid soft-drink media containing various amounts of anti-microbially active benzoic acid at pH 3.0. The results are discussed and compared to those obtained in European soft drinks.