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Clonostachys (teleomorph: Bionectria) fungi are well known to produce a variety of secondary metabolites with various biological activities to show their pharmaceutical and agrochemical applications. Up to now, at least 229 secondary metabolites, mainly including 84 nitrogen-containing metabolites, 85 polyketides, 40 terpenoids, and 20 other metabolites, have been reported. Many of these compounds exhibit biological activities, such as cytotoxic, antimicrobial, antileishmanial, antimalarial activities. This mini-review aims to summarize the diversity of the secondary metabolites as well as their occurrences in Clonostachys fungi and biological activities. [ABSTRACT FROM AUTHOR]

Nectria ganymede on decaying ascomata of Zeus olympius is reported from the Republic of North Macedonia, thus significantly extending its geographic area westwards. Gnomonia arnstadtiensis is collected on dead leaves of Ostrya carpinifolia at the Ohrid Lake. Concise descriptions and original illustrations of the studied materials are presented. [ABSTRACT FROM AUTHOR]

The new species Stilbocrea walteri is described and illustrated from Quercus ilex collected in Portugal. Phylogenetic analyses of LSU rDNA, rpb1, rpb2 and tef1 sequence matrices place S. walteri in the Bionectriaceae, Hypocreales, within a clade of specimens morphologically identified as Stilbocrea macrostoma, the generic type of Stilbocrea. Stilbocrea walteri differs from S. macrostoma in dark olive green to blackish ascomata basally immersed in a stroma, KOH+ and LA+ ascomata and the lack of a stilbella-like asexual morph on natural substrate and pure culture. A simple phialidic asexual morph is formed in pure culture. To enable a morphological comparison, Stilbocrea macrostoma is illustrated. [ABSTRACT FROM AUTHOR]

The ascomycetous dark septate endophytic (DSE) fungi characterized by their melanized hyphae can confer abiotic stress tolerance in their associated plants in addition to improving plant growth and health. In this study inoculation of the DSE fungus Nectria haematococca Berk. & Broome significantly improved all the plant growth parameters like the plant height, stem girth, leaf characteristics and plant biomass of drought-stressed tomato. Root characters like the total root length, primary root diameter, 2nd order root number and diameter, root hair number and length were also significantly influenced by the fungal inoculation. Nevertheless, N. haematococca inoculation did not affect root colonization by native arbuscular mycorrhizal (AM) fungi and no significant correlation existed between the AM and DSE fungal variables examined. The proline accumulation in shoots of N. haematococca inoculated plants was significantly higher than uninoculated plants. The present study clearly indicates for the first time the ability of the DSE fungus, N. haematococca in inducing the drought stress tolerance and promoting the growth of the host plant under water stress. [ABSTRACT FROM AUTHOR]

Species of Cosmospora are parasites of other fungi (mycoparasites), including species belonging to the Xylariales. Based on prior taxonomic work, these fungi were determined to be highly host specific. We suspected that the association of Cosmospora and their hosts could not be a result of random chance, and tested the cospeciation of Cosmospora and the their hosts with contemporary methods (e.g., ParaFit, PACo, and Jane). The cophylogeny of Cosmospora and their hosts was found to be congruent, but only host-parasite links in more recent evolutionary lineages of the host were determined as coevolutionary. Reconciliation reconstructions determined at least five host-switch events early in the evolution of Cosmospora. Additionally, the rates of evolution between Cosmospora and their hosts were unequal. This pattern is more likely to be explained by pseudocospeciation (i.e., host switches followed by cospeciation), which also produces congruent cophylogenies. [ABSTRACT FROM AUTHOR]

Two species of lichenicolous fungi on Placopsis gélida are described from Ecuador: Capronia andina (also collected from Costa Rica and Colombia) and Roselliniopsis palicei. A diagnosis of Nectria byssophila, collected for the first time in America on Stereocaulon is presented. The new combination Cosmospora marelliana is proposed and Epicymatia microspora is synonymized with Phacopsis thallicola.

On 11 December 2008, a severe ice storm affected large portions of southern New England. We report the results of a study investigating differential damage among tree species. Past studies surveying ice-damaged forests have relied heavily on ocular estimations of canopy damage. We compare this method with damage estimates based on the cross-sectional area of downed woody material and quantitative comparisons of tree height and canopy projection in damaged and undamaged stands. Ocular estimates and changes in canopy height and projection were unreliable. Estimates based on the amount of woody debris provide a more robust measure of storm damage. We assess damage in two forest tracts with a dominant red oak ( Quercus rubra L.) canopy (42% of total basal area) and an American beech ( Fagus grandifolia Ehrh.) dominated understory (50% of all stems > 1.3 m). Species' standing basal area was well correlated with the amount of newly downed woody debris ( r = 0.69, p < 0.001); accordingly, oak species constituted approximately 57% of all newly downed woody debris, and ANOVA showed that oak species were significantly more impacted by ice damage than other species present ( p < 0.001). Our findings indicate that canopy species provide an 'umbrella effect', shielding less dominant lower strata trees from the worst effects of ice load. Oak was also the largest contributor to older downed woody debris, indicative of a recurrent historical pattern of differential canopy disturbance driven by strata and relative dominance. These findings suggest that periodic ice events play an important role in facilitating the advancement of shade-tolerant tree species into the canopy from lower strata. [ABSTRACT FROM AUTHOR]

PDA1 -conditionally dispensable chromosome (CDC) of Nectria haematococca MP VI has long served as a model of supernumerary chromosomes in plant pathogenic fungi because of pathogenicity-related genes located on it. In our previous study, we showed the dosage effects of PDA1 -CDC on pathogenicity and homoserine utilization by exploiting tagged PDA1 -CDC with a marker gene. CDC content of mating partners and progenies analyzed by PCR, PFGE combined with Southern analysis and chromosome painting via FISH. In this study, we analyzed mode of meiotic inheritance of PDA1 -CDC in several mating patterns with regard to CDC content and found a correlation between CDC content of parental strains with fertility of crosses. The results showed non-Mendelian inheritance of this chromosome followed by duplication or loss of the CDC in haploid genome through meiosis that probably were due to premature centromere division, not by nondisjunction as reported for the supernumerary chromosomes in other species. Correlation of CDC with fertility is the first time to be examined in fungi in this study. [ABSTRACT FROM AUTHOR]

The genus Cosmospora includes nectrioid fungi that grow on polypores and xylariaceous fungi. The collections growing on xylariaceous fungi have been identified recently as Cosmospora viliuscula. In this paper the phylogeny and taxonomy of C. viliuscula are investigated. A phylogeny was generated with maximum likelihood and Bayesian inference methods applied to a three-partition dataset (ITS, 28S, MCM7-RPB1-TUB2). Based on these results, we demonstrate that Cosmospora viliuscula represents a diverse species complex comprising more than 10 species. Seven new species are described, including three single-strain lineages, and the sexual states of C. arxii and C. khandalensis are described for the first time. The sexual states of these fungi tend to have a high degree of morphological homoplasy, making it difficult to differentiate among them based on morphological characters alone. However, the apparent host specificity of species in this complex aide in the diagnosis of these fungi. In addition, the RPB1 marker provides sufficient resolution to distinguish these fungi. [ABSTRACT FROM AUTHOR]

Microcera coccophila has been regarded as an entomopathogen of armoured scales in Australia since the late 1800s. We confirmed its identity and presence in Australia using morphological and molecular data. We also confirmed that a related species, M. larvarum, is an entomopathogen of armoured scales in Australia. M. coccophila was recorded as a parasite of Aonidiella aurantii, A. citrina, Lepidosaphes beckii, L. gloverii and Unaspis citri in citrus orchards on the Central Coast of New South Wales. We recorded M. larvarum in these orchards in association with A. aurantii and one or more hosts that could not be identified due to their condition. The sexual and asexual morphs of both species are described. Genetic variation suggested that the taxa could represent various phylogenetic species. We fulfilled Koch's postulates for both fungi in separate bioassays with Aspidiotus nerii. Infection was not dependent on the reproductive status of the scale. A laboratory study showed that Iridomyrmex rufoniger, a common ant in Australian citrus orchards, can passively disperse conidia of M. coccophila. Field observations suggested that the prevalence of the two fungal parasites in orchards is influenced by host scale densities, climate, and foraging by I. rufoniger workers on honeydew produced by their sternorrhynchan trophobionts, particularly Saissetia oleae. These foraging activities induced dense populations of A. aurantii by disrupting the activities of the scale's natural arthropod enemies; this was followed by epizootics of M. coccophila that decimated populations of the scale. [ABSTRACT FROM AUTHOR]

Genera with cylindrocarpon-like asexual morphs are important pathogens of various herbaceous and woody plant hosts globally. Recent multi-gene studies of this generic complex indicated that the genus Ilyonectria is paraphyletic. The present study was therefore initiated to re-evaluate the generic status of Ilyonectria and at the same time address some taxonomic irregularities in the genera Cylindrodendrum and Neonectria. Using multi-gene DNA data and morphological comparisons, the genus Dactylonectria is introduced with 10 new combinations, several of which were previously treated in Ilyonectria. Two new species, D. hordeicola and D. pinicola, are also described. Furthermore, one new combination is provided in the genus Cylindrodendrum, and three new combinations in the genus Neonectria, for species previously treated in the genera Acremonium, Cylindrocarpon, Nectria and Neonectria. The aquatic genus Heliscus is reduced to synonymy under Neonectria. [ABSTRACT FROM AUTHOR]

To our best knowledge, all of the fungal immunomodulatory proteins (FIPs) have been successfully extracted and identified in Basidomycetes, with only the exception of FIP from ascomycete Nectria haematococca (FIP-nha) discovered through homology alignment most recently. In this work, a gene encoding FIP-nha was synthesized and recombinantly expressed in an Escherichia coli expression system. SDS-PAGE and MALDI-MS analyses of recombinant FIP-nha (rFIP-nha) indicated that the gene was successfully expressed. The yield of the bioactive FIP-nha protein was 42.7 mg/L. In vitro assays of biological activity indicated that the rFIP-nha caused hemagglutination of human and rabbit red blood cells, significantly stimulated mouse spleen lymphocyte proliferation, and enhanced expression of interleukin-2 (IL-2) released from mouse splenocytes, revealing a strong antitumor effect against HL60, HepG2 and MGC823. Through this work, we constructed a rapid and efficient method of FIP production, and suggested that FIP-nha is a valuable candidate for use in future medical care and pharmaceutical products. [ABSTRACT FROM AUTHOR]

During the last decade the use of transaminases for the production of pharmaceutical and fine chemical intermediates has attracted a great deal of attention. Transaminases are versatile biocatalysts for the efficient production of amine intermediates and many have ( S)-enantiospecificity. Transaminases with ( R)-specificity are needed to expand the applications of these enzymes in biocatalysis. In this work we have identified a fungal putative ( R)-specific transaminase from the Eurotiomycetes Nectria haematococca, cloned a synthetic version of this gene, demonstrated ( R)-selective deamination of several substrates including ( R)-α-methylbenzylamine, as well as production of ( R)-amines, and determined its crystal structure. The crystal structures of the holoenzyme and the complex with an inhibitor gabaculine offer the first detailed insight into the structural basis for substrate specificity and enantioselectivity of the industrially important class of ( R)-selective amine : pyruvate transaminases. Database The atomic coordinates and structure factors for the Nectria TAm in holoenzyme and gabaculine-bound forms have been deposited in the PDB as entries 4cmd and 4cmf respectively. Structured digital abstract • and by () [ABSTRACT FROM AUTHOR]

Cosmospora sensu Rossman accommodated nectroid fungi with small, reddish, smooth, thin-walled perithecia but recently was found to be polyphyletic and has been segregated into multiple genera. Not all cosmospora-like fungi have been treated systematically. Some of these species include C. vilior and many specimens often labeled "Cosmospora sp." The objectives of this research were to establish the identity of C. vilior through epitypication using a recent collection that agrees with the type specimen in morphology, host and geography and to determine its phylogenetic position within Cosmospora sensu lato and the Nectriaceae. A multilocus phylogeny was constructed based on six loci (ITS, LSU, MCM7, rpb1, tef1, tub) to estimate a phylogeny. Results from the phylogenetic analyses indicated that C. vilior forms a monophyletic group with other cosmospora-like fungi that have an acremonium-like anamorph and that parasitize Eutypa and Eutypella (Ascomycota, Sordariomycetes, Xylariales, Diatrypaceae). The group is phylogenetically distinct from other previously segregated genera. A new genus, Pseudocosmospora, is described to accommodate the type species, P. eutypellae, and nine additional species in this clade. [ABSTRACT FROM AUTHOR]

Two novel arylacetonitrilases were purified from Escherichia coli BL21-Gold (DE3) expressing nit genes from Nectria haematococca mpVI 77-13-4 (EEU45207; NitNh) and Arthroderma benhamiae CBS 112371 (EFE30690; NitAb). The nitrilases formed holoenzymes of 360 and 336 kDa through gel filtration, while their apparent subunit size in SDS-PAGE was approximately 36 and 37 kDa, respectively. The preferred substrates of the purified enzymes were phenylacetonitrile, ( R,S)-mandelonitrile, and 3-indolylacetonitrile. Both enzymes hydrolyzed ( R)-mandelonitrile preferentially but with different degrees of selectivity, the e.e.s of the product ( R)-mandelic acid being 63 and 89% in NitAb and NitNh, respectively, at pH 8.0. NitAb exhibited a higher temperature and pH stability than NitNh. Significant amounts of amide (> 5% of total product) were produced only by NitNh (from 2-cyanopyridine, ( R,S)-mandelonitrile and phenylacetonitrile). [ABSTRACT FROM AUTHOR]

Abstract: Host specificity of plant pathogens can be dictated by genes that enable pathogens to circumvent host defenses. Upon recognition of a pathogen, plants initiate defense responses that can include the production of antimicrobial compounds such as phytoalexins. The pea pathogen Nectria haematococca mating population VI (MPVI) is a filamentous ascomycete that contains a cluster of genes known as the pea pathogenicity (PEP) cluster in which the pisatin demethylase (PDA) gene resides. The PDA gene product is responsible for the detoxification of the phytoalexin pisatin, which is produced by the pea plant (Pisum sativum L.). This detoxification activity allows the pathogen to evade the phytoalexin defense mechanism. It has been proposed that the evolution of PDA and the PEP cluster reflects horizontal gene transfer (HGT). Previous observations consistent with this hypothesis include the location of the PEP cluster and PDA gene on a dispensable portion of the genome (a supernumerary chromosome), a phylogenetically discontinuous distribution of the cluster among closely related species, and a bias in G+C content and codon usage compared to other regions of the genome. In this study we compared the phylogenetic history of PDA, beta-tubulin, and translation elongation factor 1-alpha in three closely related fungi (Nectria haematococca, Fusarium oxysporum, and Neocosmospora species) to formally evaluate hypotheses regarding the origin and evolution of PDA. Our results, coupled with previous work, robustly demonstrate discordance between the gene genealogy of PDA and the organismal phylogeny of these species, and illustrate how HGT of pathogenicity genes can contribute to the expansion of host specificity in plant-pathogenic fungi. [Copyright &y& Elsevier]

Nectria flute canker is a fungal disease that results in cankers on Pinus radiata stems. The disease, caused by the pathogen Neonectria fuckeliana, is associated with commercial pruning operations that limit knot defect to a central core to promote growth of high-quality clearwood. Nectria flute canker is present in commercial plantation forests in parts of New Zealand and Chile. Symptoms of the disease, bark cracks, stem flattenings or depressions and flute cankers, were identified on 25 mature Pinus radiata trees. Trees were felled, and discs crosscut from within, and adjacent to, the disease symptoms. The discs were photographed, and three different methods were used to determine the extent of Nectria damage beyond the defect core into the valuable clearwood sheath. These methods included a visual assessment of photographs of internal damage and two quantitative methods, based on calculations of defect extent using image processing software. Overall, flute cankers were associated with the greatest degree of encased bark and severe decay pockets, and stem flattenings the least. None of the flattened stems had internal decay. The average damage to the clearwood sheath due to flute canker was 43%, whilst that for bark cracks and flattenings was 19 and 8%, respectively. Similar results were achieved using all three methods, and the preferred method would depend on the context of the study. Using a combination of all three methods provides a robust method for measuring the damage to internal wood quality by stem pathogens and other abiotic agents. [ABSTRACT FROM AUTHOR]

A large collection of strains belonging to the Fusarium solani species complex (FSSC) was isolated from soil and perithecia in primap/ forests in Sri Lanka (from fallen tree bark) and tropical Australia (Queensland, from fallen tree fruits and nuts). Portions of the translation elongation factor 1-alpha (tef1) gene, the nuclear large subunit (NLSU) and internal transcribed spacer regions (ITS) of the nuclear ribosomal RNA genes were sequenced in 52 isolates from soil and perithecia. The FSSC was divided previously into three clades with some biogeographic structure, termed Clades 1, 2 and 3. MI Sri Lankan and Australian soil isolates were found to be members of Clade 3, most grouping with the cosmopolitan soil-associated species F. falciforme. All but two Sri Lankan perithecial isolates were associated with a set of five divergent phylogenetic lineages that were associated with Clade 2. Australian perithecial isolates resided in a subclade of Clade 3 where most of the previously defined mating populations of the FSSC reside. Isolates from perithecia and those cultured from soil were always members of different species lineages, even when derived from proximal locations. The previous biogeographic assignment of Clade 2 to South America is now expanded to the worldwide tropics. Sri Lanka appears to be an important center of diversity for the FSSC. Nectria haematococca is epitypified with a collection from the type locality in Sri Lanka; its anamorph is described as a new species, Fusarium haematococcum. Neocosmospora E.F. Smith is adopted as the correct genus for Nectria haematococca. These new species are described: F. kurunegalense/Neo, kurunegalensis, F. rectiphorus/ Neo. rectiphora/, F. mahasenii/Neo. mahasenii/, F. kelerajum/Neo, keleraja. [ABSTRACT FROM AUTHOR]

The recent availability of genome sequences of four different Fusarium species offers the opportunity to perform extensive comparative analyses, in particular of repeated sequences. In a recent work, the overall content of such sequences in the genomes of three phylogenetically related Fusarium species, F. graminearum, F. verticillioides, and F. oxysporum f. sp. lycopersici has been estimated. In this study, we present an exhaustive characterization of pogo-like elements, named Fots, in four Fusarium genomes. Overall 10 Fot and two Fot-related miniature inverted-repeat transposable element families were identified, revealing a diversification of multiple lineages of pogo-like elements, some of which accompanied by a gain of introns. This analysis also showed that such elements are present in an unusual high proportion in the genomes of F. oxysporum f. sp. lycopersici and Nectria haematococca (anamorph F. solani f. sp. pisi) in contrast with most other fungal genomes in which retroelements are the most represented. Interestingly, our analysis showed that the most numerous Fot families all contain potentially active or mobilisable copies, thus conferring a mutagenic potential of these transposable elements and consequently a role in strain adaptation and genome evolution. This role is strongly reinforced when examining their genomic distribution which is clearly biased with a high proportion (more than 80%) located on strain- or species-specific regions enriched in genes involved in pathogenicity and/or adaptation. Finally, the different reproductive characteristics of the four Fusarium species allowed us to investigate the impact of the process of repeat-induced point mutations on the expansion and diversification of Fot elements. [ABSTRACT FROM AUTHOR]

Myrmaeciella caraganae was recollected in and around Vienna, Austria and found to be morphologically different generically from the type species of Myrmaeciella, M. endoleuca. We redescribe M. caraganae in the new genus Stromatonectria. Phylogenetic analyses of LSU sequences place the genus in the Bionectriaceae, Hypocreales. S. caraganae occurs on branches of Caragana spp., Colutea arborescens and Laburnum anagyroides of the Fabaceae. It is characterized by spheroid perithecia partly or entirely immersed in a Hypocrea-like stroma, a Nectria-like centrum and bicellular hyaline ascospores. Conidia of S. caraganae are produced in compound pycnidia that are formed prior to or in association with perithecia. Sporodochia but no pycnidia are formed in culture. We discuss the genus Myrmaeciella and compare S. caraganae with species of the Nectriaceae, including Nectria balansae, N. eustromatica and N. paraguayensis. [ABSTRACT FROM AUTHOR]

A series of small-scale controlled inoculation experiments has been conducted during 2005-2009 to determine whether temperature and controlled atmosphere (CA) storage conditions affect significantly the incidence of Botrytis cinerea and Neonectria galligena rots of apples and to assess whether CA regimes can be 'fine-tuned' to suppress fungal rotting. The incidence of B. cinerea and N. galligena rots on apple was reduced consistently by storage in lower temperatures (1.5-2°C). In no case was the disease incidence significantly higher than that under air storage conditions. However, the effect of CA conditions on rot development varied greatly from year to year so that overall there were no significant effects of CA conditions on the incidence of rot during storage till the following April. Thus, we can neither fine-tune CA conditions to reduce rot development nor exploit the advantages of lower storage temperatures for Cox and Bramley for this purpose due to inevitable development of low temperature breakdown. Further research is needed to study the effects of ethylene control technologies and modulated storage temperatures on rot development. [ABSTRACT FROM AUTHOR]

A new species with remarkable morphology, Nectria eustromatica, is described, based on morphology of the teleomorph and anamorph, ecology and molecular phylogenetic analyses. Nectria eustromatica is characterized by sphaeroid perithecia immersed in pseudoparenchymatous stromata formed singly or collectively on a subiculum. Despite its deviating teleomorph morphology, it is placed within Nectria sensu stricto in phylogenetic analyses of a combined dataset of LSU, ITS, rpb2 and tef1 sequences with high internal support. Nectria eustromatica has been collected specifically on Hippocrepis (Coronilla) emerus in southern Europe. The anamorph of N. eustromatica shares morphological traits with the genera Stilbella and Tubercularia but produces non-phialidic macroconidia in addition to phialoconidia. [ABSTRACT FROM AUTHOR]

Abstract: Nitrilase activity in Fusarium solani IMI196840 (approx. 1500Ul−1 of culture broth) was induced by 2-cyanopyridine. The enzyme was purified by a factor of 20.3 at a yield of 26.9%. According to gel filtration, the holoenzyme was an approx. 550-kDa homooligomer consisting of subunits with a molecular weight of approximately 40kDa, as determined by SDS-PAGE. Mass spectrometry analysis of the tryptic fragments suggested a high similarity of this enzyme to the hypothetical CN hydrolases from Aspergillus oryzae, Gibberella zeae, Gibberella moniliformis and Nectria haematococca. Circular dichroism and fluorescence spectra indicated that secondary structure content and overall tertiary structure, respectively, were almost identical in nitrilases from F. solani IMI196840 and F. solani O1. The melting temperatures of the enzymes were 49.3°C and 47.8°C, respectively. The best substrates for the purified nitrilase from F. solani IMI196840 were benzonitrile and 4-cyanopyridine, which were hydrolyzed at the rates of 144 and 312Umg−1 protein, respectively, under the optimum conditions of pH 8 and 45°C. The enzyme was highly chemoselective, producing ≤2% amides as by-products. [Copyright &y& Elsevier]

This work investigated biostimulation and bioaugmentation as strategies for removing polyurethane (PU) waste in soil. Soil microcosms were biostimulated with the PU dispersion agent "Impranil" and/or yeast extract or were bioaugmented with PU-degrading fungi, and the degradation of subsequently buried PU was determined. Fungal communities in the soil and colonizing buried PU were enumerated on solid media and were analyzed using denaturing gradient gel electrophoresis (DGGE). Biostimulation with yeast extract alone or in conjunction with Impranil increased PU degradation 62% compared to the degradation in untreated control soil and was associated with a 45% increase in putative PU degraders colonizing PU. Specific fungi were enriched in soil following biostimulation; however, few of these fungi colonized the surface of buried PU. Fungi used for soil bioaugmentation were cultivated on the surface of sterile wheat to form a mycelium rich inoculum. Wheat, when added alone to soil, increased PU degradation by 28%, suggesting that wheat biomass had a biostimulating effect. Addition of wheat colonized with Nectria haematococca, Penicillium viridicatum, Peniciiium ochrochloron, or an unidentified Mucormycotina sp. increased PU degradation a further 30 to 70%, suggesting that biostimulation and bioaugmentation were operating in concert to enhance PU degradation. Interestingly, few of the inoculated fungi could be detected by DGGE in the soil or on the surface of the PU 4 weeks after inoculation. Bioaugmentation did, however, increase the numbers of indigenous PU.degrading fungi and caused an inoculum dependent change in the composition of the native fungal populations, which may explain the increased degradation observed. These results demonstrate that both biostimulation and bioaugmentation may be viable tools for the remediation of environments contaminated with polyurethane waste. [ABSTRACT FROM AUTHOR]

Twenty-two fungi of the family Bionectriaceae (Hypocreales, Ascomycota), collected from forests in Taiwan are reported, including Bionectria byssicola, B. compactiuscula, B. grammicospora, B. ochroleuca, B. parviphialis, B. pseudostriata, B. verrucispora, Hydropisphaera ciliata, H. cf. cyatheae, H. peziza, H. suffulta, H. cf. rufofusca, Ijuhya parilis, Ijuhya sp., Nectriella cf. luteola, Nectriopsis cupulata, N. lasiodermopsis, N. sibicola, Ochronectria cf. calami, Stephanonectria keithii, Stilbocrea gracilipes and S. macrostoma. Most of them were found on recently dead broad-leaf trees. All of these species are newly recorded in Taiwan. A dichotomous key to these species is given. [ABSTRACT FROM AUTHOR]

Aim: The aim of this study was to develop molecular assays for investigating the presence and diversity of pathogenicity genes from the pea footrot pathogen Nectria haematococca (anamorph Fusarium solani f.sp. pisi) in soils. Methods and Results: Polymerase chain reaction (PCR) assays were developed to amplify four N. haematococca pathogenicity genes ( PDA, PEP1, PEP3 and PEP5) from isolates and soil-DNA from five agricultural fields with a prior footrot history. A collection of 15 fungi isolated on medium selective for Fusarium spp. exhibited variation in their virulence to peas as assessed via a disease index (DI: 0–5; no virulence to the highest virulence). PCR analyses showed that three isolates in which all four pathogenicity genes were detected resulted in the highest DI (>3·88). All four pathogenicity genes were detected in soil-DNA obtained from all five fields with a footrot disease history, but were not amplified from soils, which had no footrot history. Denaturing gradient gel electrophoresis and/or sequence analysis revealed diversity amongst the pathogenicity genes. Conclusion: The PCR assays developed herein enable the specific detection of pathogenic N. haematococca in soils without recourse to culture. Significance and Impact of the Study: Molecular assays that specifically target pathogenicity genes have the capacity to assess the presence of the footrot-causing pathogen in agricultural soils. [ABSTRACT FROM AUTHOR]

During the past decade, and in particular after the wet year 2002 and the dry year 2003, an increasing number of trees and stands of European beech ( Fagus sylvatica L.) in Bavaria were showing symptoms typical for Phytophthora diseases: increased transparency and crown dieback, small-sized and often yellowish foliage, root and collar rot and aerial bleeding cankers up to stem heights of >20 m. Between 2003 and 2007 134 mature beech stands on a broad range of geological substrates were surveyed, and collar rot and aerial bleeding cankers were found in 116 (86.6%) stands. In most stands the majority of beech trees were declining and scattered or clustered mortality occurred. Bark and soil samples were taken from 314 trees in 112 stands, and 11 Phytophthora species were recovered from 253 trees (80.6%) in 104 stands (92.9%). The most frequent species were P. citricola, P. cambivora and P. cactorum. Primary Phytophthora lesions were soon infected by a series of secondary bark pathogens, including Nectria coccinea, and wood decay fungi. In addition, infected trees were often attacked by several bark and wood boring insects leading to rapid mortality. Bark necroses were examined for their probable age in order to determine whether the onset of the current Phytophthora epidemic was correlated to rainfall rates recorded at 22 Bavarian forest ecosystem monitoring stations. A small-scale survey in nine Bavarian nurseries demonstrated regular infestations of all beech fields with the same range of Phytophthora species. The results indicate that (1) Phytophthora species are regularly associated with beech decline and may also be involved in the complex of ‘Beech Bark Disease’, (2) excessive rainfalls and droughts are triggering the disease, and (3) widespread Phytophthora infestations of nursery stock might endanger current and future silvicultural projects aiming on the replacement of non-natural conifer stands by beech dominated mixed stands. [ABSTRACT FROM AUTHOR]

Fungi are found in a wide range of environments, and the ecological and host diversity of the fungus Nectria haematococca has been shown to be due in part to unique genes on different supernumerary chromosomes. These chromosomes have been called "conditionally dispensable" (CD) since they are not needed for axenic growth but are important for expanding the host range of individual isolates. From a biological perspective, the CD chromosomes can be compared to bacterial plasmids that carry unique genes that can define the habits of these microorganisms. The current study establishes that the N. haematococca PDA1-CD chromosome, which contains the genes for pea pathogenicity (PEP cluster) on pea roots, also carries a gene(s) for the utilization of homoserine, a compound found in large amounts in pea root exudates. Competition studies demonstrate that an isolate that lacks the PEP cluster but carries a portion of the CD chromosome which includes the homoserine utilization (HUT) gene(s) is more competitive in the pea rhizosphere than an isolate without the CD chromosome. [ABSTRACT FROM AUTHOR]

Aims: The aim of the study was to isolate and characterize the endophytic fungi from the rhizomes of the Chinese traditional medicinal plant Dioscorea zingiberensis and to detect their antibacterial activities. Methods and Results: After strict sterile sample preparation, nine fungal endophytes were isolated from rhizomes of the Chinese traditional medicinal plant D. zingiberensis. The endophytes were classified by morphological traits and internal transcribed spacer (ITS) rRNA gene sequence analysis. Their ITS rDNA sequences were 99–100% identical to Nectria, Fusarium, Rhizopycnis, Acremonium and Penicillium spp. respectively. Of these, the most frequent genera were Fusarium and Nectria. One isolate, Dzf7, was unclassified on the basis of its low sequence similarity. The next closest species was Alternaria longissima ( c. 92·4% sequence similarity). Endophyte isolate Dzf5 showed the closest sequence similarity ( c. 99·5%) to an uncultured soil fungus ( ) obtained from Cedar Creek, USA. Bioassays using a modified broth dilution test were used to detect the antibacterial activity of n-butanol extracts of both mycelia and culture filtrates of D. zingiberensis showed biological activity against Bacillus subtilis, Staphylococcus haemolyticus, Escherichia coli and Xanthomonas vesicatoria. Minimal inhibitory concentration (MIC) values of the extracts were between 31·25 μg ml−1 and 125 μg ml−1. Conclusions: Endophytic fungus Dzf2 ( c. 99·8% sequence similarity to Fusarium redolens) isolated from D. zingiberensis rhizome showed the most potent antibacterial activities. Significance and Impact of the Study: Endophytic fungi isolated from D. zingiberensis may be used as potential producers of antibacterial natural products. [ABSTRACT FROM AUTHOR]

Two new azaphilone metabolites, named pseudohalonectrin A ( 1) and B ( 2), were isolated from the culture of the aquatic fungus Pseudohalonectria adversaria YMF1.01019, originally separated from submerged wood in Yunnan Province, China. Pseudohalonectrin A and B were assessed for their nematicidal activity against the pine wood nematode Bursaphelenchus xylophilus and their structures were defined after spectral analysis. This is the first report of secondary metabolites from any member of the genus Pseudohalonectria. [ABSTRACT FROM AUTHOR]

The relationship of two species of Neonectria associated with beech bark canker in North America was evaluated by comparing isolates of these and additional species of the Neonectria coccinea (Pers.:Fr.) Rossman & Samuels group found on Fagus. Gene regions in the translation elongation factor 1-alpha (EF1-α), RNA polymerase II second largest subunit (RPB2), and β-tubulin were sequenced and analyzed. Results indicate that the fungus associated with beech bark disease previously known as Neonectria coccinea var. faginata Lohman et al. (≡ Nectria coccinea (Pers.:Fr.) Fr. var. faginata Lohman et al.) should be recognized as a separate species, Neonectria faginata, distinct from Neonectria coccinea. Neonectria faginata including its anamorphic state, Cylindrocarpon faginatum C. Booth, is known only on Fagus in North America. A second species associated with beech bark disease in North America is Neonectria ditissima (Tul. & C. Tul.) Samuels & Rossman, which can be distinguished morphologically from Neonectria faginata based on ascospore size, conidial size and shape, and colony pigmentation. Morphological and molecular data indicate that Neonectria ditissima represents an older name for Neonectria galligena Bres. Similarly, the anamorphic state of Neonectria ditissima is the older epithet Cylindrocarpon heteronema with Cylindrocarpon willkommii as a synonym. Neonectria ditissima occurs on a variety of hardwood trees in North America and Europe. Neonectria coccinea occurs only on Fagus in Europe. Neonectria major (Wollenw.) Castl. & Rossman is recognized as a species that occurs only on Alnus in Canada (British Columbia), France, Norway, and the United States (Washington). The following nomenclatural changes are proposed: Neonectria faginata comb. and stat. nov., Neonectria fuckeliana comb. nov., Neonectria hederae comb. nov., Neonectria major comb. and stat. nov., and Neonectria punicea comb. nov. [ABSTRACT FROM AUTHOR]