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Rare studies investigated influence of neonicotinoid insecticides on the whole soil biota including non-target invertebrates and microorganisms. And less is known about the consequent intervention on soil C processes. This study aimed to decipher Collembola-fungi-bacteria interactive effects on pathways of maize C translocation, combining isotopic tracer analysis of relevant compartments with high-throughput sequencing for bacterial and fungal genetic profiles. Dinotefuran was applied at 0 or 100 μg kg−1 (a simulating residual dosage) to microcosms containing soils, Collembola and 13C labelled maize. Dinotefuran drastically reduced the density and maize-derived biomass C of Collembola, while intensifying antagonistic associations between soil organisms, with flourishing growth of Ascomycota and Actinobacteria, e.g., Streptomyces. This led to higher soil organic C (SOC) mineralization (elevated by 9.8–10.5%) across soils, attributing to the shift in microbial taxonomic and functional guild, e.g., with the increased abundance of genes aligned to cytochrome P450. Maize decomposition was controlled by Collembola that primarily fed on maize, via grazing behavior that facilitated labile maize C preferred decomposers, e.g., Xanthomonadaceae. These findings elucidate the influence of minute dinotefuran on intra-linkages between biomes (Collembola, fungi and bacteria), and highlight such legacy effects on maize and SOC mineralization.

Forest trees are considered important in ameliorating climate change through removing carbon dioxide from the atmosphere, stabilizing water catchments and for timber production. Wood decay fungi are among the most important biotic factors in ecosystems, infecting valuable landscaping trees causing an economic loss or the preeminent recyclers of the wood. In a survey of forest trees in the Alamdardeh forest, northern Iran, fungal fruit bodies were collected and isolations made. Based on a combination of macro-morphological characteristics and molecular analyses, using the sequence data of ITS-rDNA, isolates were identified to the species level. A total of 22 species in nine families and 15 genera were identified. Most isolates were the white-rot fungi. Additionally, the brown-rot fungus Laetiporus sulphureus and the soft-rot species Xylaria longipes were identified.

This research assessed the destructive behaviors of two white-rot fungi, Pleurotus ostreatus and Trametes versicolor and compared their degradation capabilities on solid oriental beech wood (Fagus orientalis Lipsky). Beech wood specimens were exposed to both fungi for a period of 120 days based on the specifications in the EN-113 standard. Mechanical properties and chemical composition of the specimens were measured every 15 days. Mass loss (ML) caused by the two fungi were not significantly different at the last stage of exposure, although T. versicolor showed higher ML at the middle exposure intervals. Compression strength parallel to grain, hardness, and impact bending values were higher in specimens exposed to P. ostreatus, although differences were not statistically significant. Microscopic images showed nearly the same decay patterns for both fungi. The results of the chemical assessment indicated that degradation of cell wall components was approximately the same for both fungi, but in some case T. versicolor showed a slightly higher potential to decay compared to P. ostreatus, especially in the early stages of exposure. The two fungi differed in their ability to reduce degree of polymerization (DP) holocellulose of beech wood. It was concluded that the destructive behaviors ability of both fungi was considerable.

We performed a greenhouse experiment to test how the functional diversity of earthworms, the dominant group of soil macro-invertebrates in many terrestrial ecosystems, affects nitrogen cycling and plant growth. Three species were chosen to represent a range of functional traits: Lumbricus terrestris (large, mainly detritivorous, makes vertical permanent burrows open at the surface), Aporrectodea longa (medium-large, feeds on both detritus and soil, makes burrows more branched than L. terrestris), and Allolobophora chlorotica (small, geophagous, makes ephemeral burrows below the soil surface). Mesocosms with ryegrass (Lolium perenne) were inoculated with none to all three species (similar total biomass), using an experimental design (Simplex) suited to partition single species and diversity effects. Two contrasting N sources, urea or mammalian dung, were labelled with 15N so that the acquisition by plants and earthworms and recovery of applied 15N could be estimated. Over 3 months, plant production was higher with urea applications, but there were also species-specific earthworm effects: A. chlorotica and, to a lesser extent, A. longa increased shoot biomass, whereas L. terrestris increased root biomass. Earthworms did not affect soil N concentrations or leaching losses, whereas more N was leached under urea. A. chlorotica tended to increase dung-15N recovery in grass shoots, but in interaction with A. longa had the opposite effect, possibly through increased N immobilization in the microbial biomass. Earthworms assimilated negligible amounts of urea-15N but a substantial proportion (17% on average) of the dung-15N, with no clear-cut differences between species. Our findings show that earthworm species may have similar trophic response to N sources and yet different effects on plant N uptake and primary production, and that inter-specific earthworm interactions can result in non-additive diversity effects.

Oil palm wood samples were subjected to decay by the brown-rot fungus Coniophora puteana and the white-rot species Pleurotus ostreatus. There was up to 61% mass loss by C. puteana and 32% by P. ostreatus within two month of incubation. Light microscopy of the decayed samples showed preferential degradation of the parenchymatous ground tissue and phloem in the vascular bundles. Transmission electron microscopy revealed details on the micromorphology of cell wall decay. C. puteana consumed the carbohydrates. P. ostreatus produced simultaneous white-rot. Ultraviolet microspectrophotometry provided insight in lignin degradation by P. ostreatus showing lignin decrease in the walls of parenchyma cells, fibers and vessels. C. puteana increased the UV absorbance due to depolymerization of the lignocelluloses matrix and modifications in the lignin side chains.

Freshly harvested palm trunks and timber with their high moisture content (MC) are susceptible to fungi due to the high content of easily consumable sugars and starch as long as MC of the tissue is above fiber saturation point (FSP). To test the influence of sugars and starch on fungal development, small wood samples from oil palm (Elaeis guineensis) were watered and their contents of the non-structural carbohydrates were measured. Glucose was the most abundant substance in the extract, followed by starch, fructose, and sucrose. Watering for 3 and 10 days with daily water exchange reduced the content of sugars and starch considerably. Untreated and watered samples were then subjected to spore suspensions of the moulds Aspergillus niger, Penicillium commune, to a natural infection by air-born spores and to the blue-stain-fungi Alternaria alternata and Aureobasidium pullulans. The former colonized the surface of the untreated samples within a few days, while the latter caused considerable mass loss. With increasing watering both fungal activities were reduced as the nutrients for the fungi were removed. The woods of E. guineensis and Phoenix dactylifera (date palm) with MC above FSP were treated with acetic and propionic acid and subsequently infected by moulds, staining and decay fungi. Short dipping in solutions of 2% acetic acid and 2% propionic acid, respectively, protected all samples for 3 months against the mould fungi. Staining fungi and wood-decay fungi were slightly inhibited by a treatment with 5% acid concentration. Treatment with these acids offers a protection technique for the practice. Their sodium salts were ineffective due to their high pH-value.

The scope of this research was to evaluate the influence of xylem ray (XR) and degree of polymerization (DP) of holocellulose in Oriental beech wood (Fagus orientalis Lipsky.) on impact bending strength against two white-rot fungi. Beech wood specimens, exposed to Pleurotus ostreatus and Trametes versicolor, were evaluated for impact bending strength at 15-day intervals for 120 days. Microscopic evaluations at each time interval indicated that both fungi degraded marginal ray parenchyma at early stages of decomposition causing a drastic loss in impact bending strength. However, the two fungi differed in their ability to reduce DP; DP and xylem ray integrity (without precedence) were the most important factors in mechanical stability of beech wood.

The degradation capabilities of two white rot fungi, Pleurotus ostreatus and Trametes versicolor, obtained from natural stands of Fagus orientalis (beech) in Northern Iran were studied. Fruiting bodies of P. ostreatus and T. versicolor were collected from fallen beech in the Alamdardeh forest, Iran. Beech wood samples were exposed to both fungi for 120 days according to EN113. Mass loss, resistance to compression parallel to grain, impact load resistance, as well as lignin, cellulose and hemicellulose content were determined in the samples before and after fungal exposure. FT-IR spectroscopy was used to collect spectra after fungal decay. Light and electron microscopy were used to study white-rot decay patterns in wood and compare the mechanism of attack for both fungi. Both fungi reduced wood mass and chemical constituents in similar quantities. Chemical analyses indicated similar reductions in cellulose, lignin and total carbohydrates. Both fungi had negligible affect on the hemicelluloses, arabinan, galactan, and glucan. Patterns of white decay were the same for both fungi. Thinning of the cell walls, colonization of fungal hyphae as well as formation of bore holes on the cell wallswere also similar for both fungi. The results demonstrated that both fungi produced a simultaneous white rot in beech wood.

Summary Chemical, light and electron microscopic studies were carried out on wood of Oriental beech (Fagus orientalis Lipsky) decayed by the white-rot fungi Pleurotus ostreatus and Trametes versicolor for 30, 60 and 120 days according to the modified European standard EN 113. Mass loss as well as lignin, cellulose and carbohydrate content were determined before and after fungal attack. There were no significant differences of wood mass loss and chemical composition between both fungi at the end of incubation. After each incubation period, small specimens were stained for microscopic studies. The micromorphology of fungal cell wall degradation was rather similar for both fungi. Both decreased the cell wall thickness to the same extent. The accumulation of hyphae as well as the rupture of cell walls was also similar. The occurrence of hyphae, cavities in the pits and vessel walls followed nearly the same patterns. The parenchyma cells were completely destroyed. Altogether, both fungi produced a simultaneous white rot in Oriental beech wood.

Effects of nano-clay on weight loss of wood-plastic composites (WPC) by five fungi were studied. Nanoclay particles of 20 to 50 nm size were applied at 2, 4, and 6% WPC of 0,90 g/cm3 density. The white-rot fungi Physisporinus vitreus, Pleurotus ostreatus and Trametes versicolor as well as the brown-rot species Antrodia vaillantii and Coniophora puteana were used. Mass loss tests were conducted according to the European standard. The highest (3.2%) and lowest (0,2%) mass losses were produced by T. versicolor and P. vitreus in the control and 6%-nanoclay treatments, respectively. Obviously the weight loss of WPC depends on the fungus species. Although weight losses were extremely low, nano-clay considerably inhibited the growth of wood-deteriorating fungi. Mass loss correlated with water absorption.

Felled palm trunks are susceptible to fungi as long as their moisture content is above fibre saturation. During this period, palm wood has to be protected against mould and rot fungi. The study was aimed at testing environment-friendly organic acids for their protecting efficiency. Small samples of date palm (Phoenix dactylifera) and oil palm (Elaeis guineensis) wood were treated with weak organic acids and subsequently infected by moulds and wood-decay fungi. Short dipping of the samples in solutions of 5% acetic acid and propionic acid, respectively, protected all samples for two months from colonization by Aspergillus niger, Penicillium sp., Cladosporium sp. and by a natural infection. Boric acid (4%) used in practice for protection was ineffective. Decay tests with the white-rot fungus Pleurotus ostreatus, the brown-rot species Coniophora puteana and the soft-rot fungus Chaetomium globosum showed that both acids prevented most samples from fungal colonization for three weeks and reduced the de...

The effects of exposing specimens of Oriental beech [Fagus sylvatica subsp. orientalis (Lipsky) Greuter and Burdet] to the white-rot fungi Pleurotus ostreatus (Jacq.: Fr.) Kummer and Trametes versicolor (L.: Fr.) Pilát strain 325 have been studied concerning the mechanical properties and chemical composition in terms of carbohydrates, cellulose, and lignin. Biological decay tests were carried out in accordance with the EN 113 standard specifications for 30 and 120 days. P. ostreatus had nearly the same deteriorating effects on the mechanical properties and chemical composition as that caused by T. versicolor. High and significant correlations were found between some mechanical properties with chemical components; for instance, the correlation coefficient (R2) between impact bending and carbohydrate content was about 0.96. The changes of components influence the various mechanical properties to a different degree. Incipient fungal decay caused severe changes for impact bending and carbohydrate loss. Several other properties declined at 120-day exposure time, such as the hardness, compression strength parallel to grain, and cellulose and lignin losses.

Some of the most important indoor wood-decay basidiomycetes were investigated in Erlenmeyer flask experiments, in which 50 Pinus sylvestris sapwood samples with moisture content (MC) of 16% were piled, in view of the parallel influence of wood moisture and temperature on decay in buildings. In the piles, the moisture flow from the liquid at the bottom was interrupted by a metal ring at layer 7. Laboratory incubations with Antrodia xantha, Coniophora puteana, Donkioporia expansa, and Gloeophyllum abietinum over the temperature range of 10°C–25°C showed that fungi are able to colonize, moisten, and thereafter degrade wood samples below fiber saturation, if a moisture source nearby is available. In extreme cases, mycelium grew on wood with 17.4% final MC, and wood mass loss of more than 2% occurred at 24.6% moisture.

The durability of five bamboo species from various origin against brown-, white- and soft-rot fungi was investigated in Kolle flasks in accordance with the European standards EN 350-1, EN 350-2 and EN 113. Considerable variability exists in the durability of the bamboo species. Guadua angustifolia was rather resistant to Trametes versicolor and Dendrocalamus asper against Chaetomium globosum. Among the brown-rot fungi, the four strains of Coniophora puteana and two strains of Gloeophyllum trabeum produced low mass loss (maximum 2.9 %). Of the white-rot fungi, T. versicolor yielded the highest decay (max. 15.3 %), whereas Schizophyllum commune was rather inactive (max. 3.2 %). Of the soft-rot fungi, Ch. globosum showed medium degradation (max. 9.6 %) and Paecilomyces variotii low decay (max. 3.1 %).

We tested experimentally if photoautotrophic microorganisms are a carbon source for invertebrates in temperate soils. We exposed forest or arable soils to a 13 CO 2 -enriched atmosphere and quantified 13 C assimilation by three common animal groups: earthworms (Oligochaeta), springtails (Hexapoda) and slugs (Gastropoda). Endogeic earthworms ( Allolobophora chlorotica ) and hemiedaphic springtails ( Ceratophysella denticulata ) were highly 13 C enriched when incubated under light, deriving up to 3.0 and 17.0%, respectively, of their body carbon from the microbial source in 7 days. Earthworms assimilated more 13 C in undisturbed soil than when the microbial material was mixed into the soil, presumably reflecting selective surface grazing. By contrast, neither adult nor newly hatched terrestrial slugs ( Deroceras reticulatum ) grazed on algal mats. Non-photosynthetic 13 CO 2 fixation in the dark was negligible. We conclude from these preliminary laboratory experiments that, in addition to litter and root-derived carbon from vascular plants, photoautotrophic soil surface microorganisms (cyanobacteria, algae) may be an ecologically important carbon input route for temperate soil animals that are traditionally assigned to the decomposer channel in soil food web models and carbon cycling studies.

Soil nematode feeding groups are a long-established trophic categorisation largely based on morphology and are used in ecological indices to monitor and analyse the biological state of soils. Stable isotope ratio analysis (13C/12C and15N/14N, expressed asδ13C andδ15N) has provided verification of, and novel insights into, the feeding ecology of soil animals such as earthworms and mites. However, isotopic studies of soil nematodes have been limited to date as conventional stable isotope ratio analysis needs impractically large numbers of nematodes (up to 1,000) to achieve required minimum sample weights (typically >100 µg C and N). Here, micro-sample near-conventional elemental analysis–isotopic ratio mass spectrometry (μEA–IRMS) of C and N using microgram samples (typically 20 µg dry weight), was employed to compare the trophic position of selected soil nematode taxa from four feeding groups: predators (AnatonchusandMononchus), bacterial feeders (PlectusandRhabditis), omnivores (Aporcelaimidae and Qudsianematidae) and plant feeder (Rotylenchus). Free-living nematodes were collected from conventionally and organically managed arable soils. As few as 15 nematodes, for omnivores and predators, were sufficient to reach the 20 µg dry weight target. There was no significant difference inδ15N (p= 0.290) orδ13C (p= 0.706) between conventional and organic agronomic treatments but, within treatments, there was a significant difference in N and C stable isotope ratios between the plant feeder,Rotylenchus(δ15N = 1.08 to 3.22 mUr‰,δ13C = –29.58 to –27.87 mUr) and all other groups. There was an average difference of 9.62 mUr inδ15N between the plant feeder and the predator group (δ15N = 9.89 to 12.79 mUr,δ13C = –27.04 to –25.51 mUr). Isotopic niche widths were calculated as Bayesian derived standard ellipse areas and were smallest for the plant feeder (1.37 mUr2) and the predators (1.73 mUr2), but largest for omnivores (3.83 mUr2). These data may reflect more preferential feeding by the plant feeder and predators, as assumed by classical morphology-based feeding groups, and indicate that omnivory may be more widespread across detritivore groups i.e. bacterial feeders (3.81 mUr2). Trophic information for soil nematodes derived from stable isotope analysis, scaled as finely as species level in some cases, will complement existing indices for soil biological assessment and monitoring, and can potentially be used to identify new trophic interactions in soils. The isotopic technique used here, to compare nematode feeding group members largely confirm their trophic relations based on morphological studies.

By living in permanent burrows and incorporating organic detritus from the soil surface, anecic earthworms contribute to soil heterogeneity, but their impact is still under-studied in natural field conditions. We investigated the effects of the anecic earthworm Lumbricus centralis on fresh carbon (C) incorporation, soil organic matter composition, protists, and nematodes of a Cambisol under grassland. We used plant material labelled with stable isotope tracers to detect fresh C input around earthworm-occupied burrows or around burrows from which the earthworm had been removed. After 50 days, we sampled soil (0--10 cm depth) in concentric layers around the burrows, distinguishing between drilosphere (0--8 mm) and bulk soil (50--75 mm). L. centralis effectively incorporated fresh C into the drilosphere, and this shifted soil organic matter amount and chemistry: total soil sugar content was increased compared to unoccupied drilosphere and bulk soil, and the contribution of plant-derived sugars to soil organic matter was enhanced. Earthworms also shifted the spatial distribution of soil C towards the drilosphere. The total abundance of protists and nematodes was only slightly higher in earthworm-occupied drilosphere, but strong positive effects were found for some protist clades (e.g. Stenamoeba spp.). Additional data for the co-occurring anecic earthworm species Aporrectodea longa showed that it incorporated fresh C less than L. centralis, suggesting that the two species may have different effects on soil C distribution and organic matter quality.

Lumbricus terrestris is a deep-burrowing anecic earthworm that builds permanent, vertical burrows with linings (e.g., drilosphere) that are stable and long-lived microhabitats for bacteria, fungi, micro- and mesofauna. We conducted the first non-culture based field study to assess simultaneously the drilosphere (here sampled as 0–2 mm burrow lining) composition of microbial and micro/mesofaunal communities relative to bulk soil. Our study also included a treatment of surface-applied 13C- and 15N-labeled plant residue to trace the short-term (40 d) translocation of residue C and N into the drilosphere, and potentially the assimilation of residue C into drilosphere microbial phospholipid fatty acids (PLFAs). Total C concentration was 23%, microbial PLFA biomass was 58%, and PLFAs associated with protozoa, nematodes, Collembola and other fauna were 200-to-300% greater in the drilosphere than in nearby bulk soil. Principal components analysis of community PLFAs revealed that distributions of Gram-negative bacteria and actinomycetes and other Gram-positive bacteria were highly variable among drilosphere samples, and that drilosphere communities were distinct from bulk soil communities due to the atypical distribution of PLFA biomarkers for micro- and mesofauna. The degree of microbial PLFA 13C enrichment in drilosphere soils receiving 13C-labeled residue was highly variable, and only one PLFA, 18:1ω9c, was significantly enriched. In contrast, 11 PLFAs from diverse microbial groups where enriched in response to residue amendment in bulk soil 0–5 cm deep. Among control soils, however, a significant δ13C shift between drilosphere and bulk soil at the same depth (5–15 cm) revealed the importance of L. terrestris for translocating perennial ryegrass-derived C into the soil at depth, where we estimated the contribution of the recent grass C (8 years) to be at least 26% of the drilosphere soil C. We conclude that L. terrestris facilitates the translocation of plant C into soil at depth and promotes the maintenance of distinct soil microbial and faunal communities that are unlike those found in the bulk soil.

Trees are valuable for urban areas, however, are also susceptible to wood rot fungi. For accurate and fast assessment of the severity and evolution of decay in standing trees, a molecular technique was used to identify the causal agents of wood rot. Fruit bodies of wood decay fungi were collected from infected trees in various stands in Germany. Thirty-six species were identified by traditional methods. The DNA of fruit bodies was extracted, ITS-rDNA amplified by PCR, and ITS regions sequenced. Wood samples from infected urban trees were collected, the entire DNA extracted from affected wood parts, and fungal ITS amplified and sequenced. Fungal species were identified by comparing sequence data with the fruit body data. The technique enables an accurate and rapid identification of causal rot fungi in urban trees.

Summary 1. Labelling plants with 15 Na nd 13 C stable isotopes usually require cultivation of plants in isotopically enriched soil and gas-tight labelling chambers - both approaches are not suitable if one aims to investigate in situ species interactions in real plant communities. 2. In this greenhouse experiment, we tested a labelling method in which dual-labelled ( 15 N, 13 C) urea solution is brushed directly onto leaves of twelve temperate grassland species representing grasses, non-leguminous forbs and legumes. 3. Across all plant species, shoots ( 15 N: 0AE145; 13 C: 0AE090 atom percent excess, APE) and roots ( 15 N: 0AE051; 13 C: 0AE023 APE) were significantly enriched after five daily labelling events. Generally, isotopic enrichments were significantly higher in shoots than in roots. No clear pattern of absolute isotopic enrichment was observed between plant functional groups; however, grasses showed a more even allocation between shoots and roots than forbs and legumes. Isotopic enrichment levels after 4 weeks were lower, higher or unchanged compared to those of week one and varied between species or plant parts. 4. Considering the consistent enrichment levels and simplicity of this method, we conclude that it can be applied widely in ecological studies of above-belowground plant–plant or plant–animal interactions even in real plant communities.

Indoor wood-decay fungi are economically very important. Approximately half of the total damage caused by indoor fungi in Germany is caused by species of the Coniophoraceae. The sequence of the intergenic spacer (IGS) region of the ribosomal DNA was elucidated with the following fungi of this family: Serpula lacrymans (true dry rot fungus), S. himantioides (wild merulius), Meruliporia incrassata (North American dry rot fungus), Leuco-gyrophana pinastri (mine dry rot fungus), Coniophora puteana (brown cellar fungus), and C. marmorata (marmoreus cellar fungus). The IGS length ranges between 2584 and 3785 bp and consists of the short IGS 1 (253–440 bp), the 5S rDNA (118 bp) and the long IGS 2 (2193–3310 bp). IGS 1 is phylogenetically less informative for the investigated Coniophoraceae species. 5S rDNA is transcribed in the reverse direction. IGS 2 contains extended repeat blocks of copies of different length. Intraspecific length polymorphism as a result of different copy number occurs in M. incrassata and L. pinastri. In combination with previous results, the full-length sequence of the rDNA repeat unit is available for important indoor wood-decay fungi. The various rDNA regions can now be used for future identification of unknown sequences by BLAST and also for phylogenetic studies.

Net carbon isotope discrimination (13CΔn) in leaves from Thuja plicata, Larix × eurolepis and Picea sitchensis was assessed with the aim of exploring the potential use of leaf carbon isotope signatures as a physiological marker for the selection of shade-tolerant tree species. Leaf 13CΔn varied from 14.2‰ to 26.7‰ depending on incident irradiance and species and was negatively correlated with annual biomass increment. Under shaded conditions, variations in 13CΔn values were consistent with differences in instantaneous nitrogen use efficiency and the ratio of sub-stomatal internal to external CO2 concentration (Ci:Ca). Although changes in 13CΔn were consistent variations in instantaneous photosynthetic discrimination (13CΔi) across all irradiances, we suggest that species-specific variations in Ci:Ca and other isotopic fractionation processes may influence 13CΔn. We demonstrate that 13CΔn can be used to rank species according to shade tolerance (T. plicata > P. sitchensis > L. eurolepis) under shaded conditions only. Therefore, the proposed use of 13CΔn to select shade tolerance should be approached with caution because the ranking of individual species may depend on the light environment to which the material is exposed and what photosynthetic and other metabolic characteristics influence 13CΔn.

An identification key for 20 common strand-forming indoor wood decay fungi is given. The key is based on observations of material from affected buildings and on wood samples that have been incubated in the laboratory. The key is with macro- and microscopic photographs.

Untersucht wurden die Letaltemperaturen von acht Hausfaulepilzen. Alle Pilze vertrugen in getrockneten Holzproben deutlich hohere Temperaturen als auf Agar: Donkioporia expansa und die Gloeophyllum-Arten uberlebten vier Stunden 95°C, Antrodia vaillantii und Oligoporus placenta 80°C, Leucogyrophana mollusca und Coniophora puteana 70°C und Serpula lacrymans 65°C. Diese Befunde werden im Hinblick auf Heisluftbehandlungen diskutiert. Laborversuche und Beobachtungen aus uber 40 Hausschwammbefallen in Gebauden im Hamburger Raum zeigten nur geringen Wassertransport durch das Mycel. Bei S. lacrymans lag die maximale Befeuchtungsgeschwindigkeit bei drei Millimetern pro Woche. Die minimale Holzfeuchtigkeit fur den Abbau von Kiefernholz betrug fur S. lacrymans 26,2% u, das Optimum in der Initialphase 35–55% u und bei starkstem Holzabbau 45–90% u; das Maximum lag uber 220% u. Insgesamt wurden 37 verschiedene Hausfaulepilze nachgewiesen, sechs davon erstmals. S. lacrymans war der haufigste Pilz. In Gebauden scheint sich eine Verschiebung im Artenspektrum zu Pilzen mit hoheren Feuchtigkeitsanspruchen abzuzeichnen, die auch das Vorkommen von Schleimpilzen einschliest. Ein Zusammenhang mit dem verstarkten Warmeschutz in Altbauten wird vermutet.

A simple, rapid and cost-effective laboratory method was developed for labelling soil-feeding earthworms simultaneously with 15N and 13C. The method circumvents the production of labelled plant material and can be adapted to devise pulse-labelling or long-term labelling protocols. Soil was amended with 15NH4+ and incubated for 7 days. Then, U-13C-glucose was added and endogeic earthworms, Aporrectodea caliginosa (Oligochaeta: Lumbricidae), were provided individually with 4 g of this pre-incubated soil. The labelling period was 4 days. The labelling efficiency (percentage of tracer retained in earthworm tissues) was estimated to be 15.8% for 15N and 10.3% for 13C. The loss of 15N and 13C label from tissue and mucus was traced for 21 days post-labelling. Label loss from mucus was best described by a two-term exponential function, whereas the label loss in body tissue followed a single-term exponential function. Half-life estimates for the 15N and 13C tracers in body tissue were 16 and 37 days, respectively.

cause wood decay in buildings. Withregard to remedial treatment of the damage caused bythese fungi and for scientific purposes, species identityshould be known. An identification key on the basis offruit bodies is in the Internet (Huckfeldt 2002), and a keywas developed for species that form mycelial cords(Huckfeldt and Schmidt 2004). However, often only veg-etative mycelium is found in buildings. Furthermore,experience has shown that some cultures held in straincollections need re-identification (Schmidt et al. 2002;Schmidt and Moreth 2003a). Keys based on morpholog-ical and physiological characters of the vegetative myce-lium cannot discriminate closely related species. Thus,molecular methods were used for wood decay fungi (Pal-freyman 1998; Schmidt 2000; Jasalavich et al. 2000;Adair et al. 2002; Diehl et al. 2004). SDS-PAGE of pro-teins discriminated

The devastating dry rot fungus, Serpula lacrymans , has a worldwide occurrence in buildings. We investigated the genetic variation in European isolates belonging to five vegetative compatibility groups (VCGs) by AFLP analysis. Our results indicate that S. lacrymans in Europe is genetically extremely homogenous; only five out of 308 scored AFLP fragments (1.6%) were polymorphic. In contrast, S. himantioides , the closest relative of S. lacrymans , possessed 31.3% polymorphic fragments (84 out of 268). AFLP polymorphisms observed in S. lacrymans were distributed independently of the VCG boundaries, indicating that the VCGs do not represent clones but that different genets of S. lacrymans frequently share similar vic alleles due to low genetic variation. Thus, although the European S. lacrymans is genetically extremely homogeneous, and our results suggest that the species reproduces and spreads mainly sexually and not by clones.

Summary Antrodia vaillantii (DC.: Fr.) Ryv., A. serialis (Fr.) Donk, A. sinuosa (Fr.) P. Karsten, A. xantha (Fr.: Fr.) Ryv. and Oligoporus placenta (Fr.) Gilb.& Ryv. form a group of internal brown-rot fungi (‘Porenschwämme’), which are associated with decay of coniferous woodwork in buildings and timber in ground contact. The fungi have similar occurrence, biology, fruit bodies and mycelia. Their nomenclature has a confusing history and is still not uniform. For a better understanding of the domestic pore fungi and for a reliable species differentiation and identification of isolates, the internal transcribed spacer (ITS) of the ribosomal DNA (rDNA) was amplified by polymerase chain reaction and sequenced. Isolates from decayed wood and from culture collections were used. The ITS sequences characteristic of A. vaillantii, A. serialis,A. sinuosa, A. xantha and O. placenta were obtained and deposited in the international databases. The ITS size ranges from 636 to 668 bp. Intraspecific variation was low. A dendrogram was performed for the phylogenetic relationship. Some isolates obtained mislabelled were named correctly according to the ITS sequence. The sequences contribute to our collection of ITS data from internal wood decay fungi made to characterize fungi in culture.

Summary Within the genus Coniophora, C. puteana and the less common species C. marmorata, C. arida and C. olivacea form a group of domestic brown-rot fungi (“cellar fungi”), which cause considerable decay in the woodwork of buildings. The fungi are difficult to distinguish by their fruit bodies. Traditional methods fail to identify species in a pure culture. Also with regard to decay of wood in use, the basidiomes rarely develop, and the surface mycelium on wood is sparse except for the fine dark strands. Thus, molecular techniques were applied to obtain a reliable method for differentiation and detection and to aquire a greater knowledge of the domestic Coniophora species. Isolates obtained from decayed wood and from culture collections and identified as domestic Coniophora species were used. The internal transcribed spacer (ITS) of the ribosomal DNA was amplified by polymerase chain reaction, sequenced and restricted by the endonuclease TaqI. The ITS sequences characteristic of C. puteana, C. arida, C. marmorata and C. olivacea were obtained and entered into the international databases. The sequence size ranges from 525 to 729 bp. The data supplement our collection of ITS sequences from domestic wood decay fungi built for the characterization of mycelium in culture. Most isolates belong to C. puteana and some to C. arida, C. marmorata and C. olivacea. Two other isolates belong to a further Coniophora species close to C. olivacea. Obviously, at least five Coniophora species occur within European buildings. Many of the isolates were not correctly identified. Consequently, the traditional characterization methods used, viz., growth rate, temperature influence and wood weight loss, were less suitable for the differentiation of Coniophora species as formerly anticipated.

Summary Stable isotope tracers are a promising tool for investigating the ecology of terrestrial slugs, including predator-prey relationships, migration behaviour, nutrient turnover and dietary routing. The objective of the present feasibility study was to label two economically important slug groups, Deroceras reticulatum and keeled slugs (families Limacidae and Milacidae, respectively), with the stable isotope 15 N under controlled laboratory conditions. Significant isotopic enrichment in slug tissue was detected after 4 days and persisted for at least 10 days after slugs had been fed on 15 N enriched food for a period of 15 days. The time course of 15 N uptake into slug tissues and its relation to food consumption were well described mathematically. Estimated mean 15 N assimilation efficiencies from labelled maize mixed with unlabelled wheat bran were 30% and 38%, respectively, for the species groups studied. These findings suggest that slugs can be readily and efficiently labelled and that it is feasible to devise protocols for producing large numbers of isotopically labelled slugs for use in ecological studies. A simple method is described for the collection and analysis of cutaneous mucus from individual slugs which can be used to test uniformity of isotopic labelling.

Summary In this research, we examined decay patterns occurring in Quercus castaneifolia wood under natural conditions compared with controlled decay in vivo. Pleurotus ostreatus-infected oak wood was obtained from the Sari forests in the north of Iran. The species causing decay was verified as P. ostreatus using rDNA-ITS sequencing of pure cultures from infected sapwood. In addition to P. ostreatus, two wood-inhabiting Ascomycota, Trichoderma harzianum and T. lixii, were present. Mass loss in oak sapwood samples exposed to P. ostreatus for 60 days was around 10 per cent. Samples were prepared from both naturally decayed wood and wood decayed under controlled conditions and examined using microscopy. P. ostreatus was found to produce a simultaneous white-rot decay pattern in both conditions.

Decayed-wood samples were collected from a naturally-infected bridge made of Quercus robur. Fruiting bodies of the white-rot basidiomycetes Hymenochaete rubiginosa and Stereum hirsutum were sampled. The white-rot fungus Fuscoporia ferrea and the secondary saprobiont Mycena galericulata were identified from the rotten wood by means of rDNA-ITS sequencing. The topochemistry of lignin degradation within individual cell-wall layers was determined by cellular UV-microspectrophotometry (UMSP) at 278 nm wavelength. Increased delignification occurred in compound middle lamella regions (CML), secondary wall layers of fibres (S2), longitudinal and ray parenchyma cells as well in vessels. The highest lignin content at initial and medium decay was recorded in the CML, whereas in advanced decay secondary wall layers of the vessels exhibited the highest content of residual lignin. In all stages of degradation, the S2 layers of fibres had the lowest lignin amount.

The use of 13C isotope tracer techniques in terrestrial ecology has been restricted by the technical requirements and high costs associated with the production of 13C enriched plant material by 13CO2 release in labelling chambers. We describe a novel, simple and relatively inexpensive method for the small-scale production of 13C and 15N labelled plant material. The method is based on foliar feeding of plants with a urea solution (97 atom% 13C, 2 atom% 15N) by daily misting. Maize was grown in a greenhouse in a compost–soil mixture and enclosed in clear polythene bags between urea applications. Final enrichment in 27 d old maize shoots was 211‰ δ13C (≈1.34 atom% 13C) and 434‰ δ15N (≈0.52 atom% 15N). Enrichments of hot-water extractable fractions (289‰ δ13C, 469‰ δ15N) were only slightly higher than those observed in plant bulk material, which suggests that daily urea applications ensured fairly uniform labelling of different biochemical fractions and plant tissues. Recovery of applied excess 13C and 15N in plant shoots was 22% and 42%, respectively. Roots were less enriched (21‰ δ13C and 277‰ δ15N), but no attempts were made to recover roots quantitatively.

Summary Novel methods developed for characterization and identification of wood-inhabiting fungi target molecules of the organisms such as proteins and nucleic acids and use mycelial interaction, mating, antibodies, electrophoretic protein patterns, oligonucleotide primers and DNA sequencing. The article reviews the respective work on the dry rot fungus Serpula lacrymans in the Hamburg institute and also covers the international literature.

Various isolates of the dry rot fungus, Serpula lacrymans, the wild merulius. S. himantioides, and the cellar fungus. Coniophora puteana, from Asia, Europe and USA were investigated by the polymerase chain reaction (PCR) based technique of randomly amplified polymorphic DNA (RAPD). The banding patterns obtained revealed for S. lacrymans a rather species-specific reaction which may be used to distinguish the dry rot fungus from other indoor rot species. On the other hand. the isolates of the wild merulius and the cellar fungus showed more polymorphisms possibly suitable for identification of individual isolates.

The natural abundances of the stable isotopes of nitrogen (δ 15 N) and carbon (δ 13 C) were measured in plant shoots and in seven earthworm (Lumbricidae) species from a wheat and a wheat-clover cropping system. Variations in earthworm δ 13 C were generally small in these systems containing only C 3 plants. Plant shoot δ 15 N ranged from −2.2‰ to −0.7‰ in white clover and from +0.9‰ to +6.6‰ in winter wheat. Intraspecific variability in earthworm δ 15 N was small. Earthworm δ 15 N was significantly related to the cropping system and to the ecological grouping of the earthworms. Mean δ 15 N values of all earthworm groups were significantly lower (by 3.5‰ to 4.4‰) in the wheat-clover field than in the wheat field. Within each of the two cropping systems, earthworm nitrogen isotope ratios differed significantly between ecological earthworm groups, with δ 15 N values decreasing in the order Allolobophora chlorotica and Aporrectodea caliginosa > Aporrectodea longa > Lumbricus spp. These results demonstrate for the first time that the δ 15 N signature of legumes can influence those of soil invertebrates. Because isotope measurements reflect assimilated tissue nitrogen, they offer novel insights into the feeding ecology and trophic positions of earthworms.

Earthworm food was tested as a carrier and inoculum source for Pseudomonas corrugata 2140R, a biocontrol agent for Take-all disease of wheat, in order to use the feeding, burrowing and casting activity of earthworms to disperse the biocontrol agent through soil. Three experiments are reported here using a bioluminescent derivative, P. corrugata 2140R lux8 (hereinafter called P. corrugata). In the first experiment, P. corrugata was inoculated into autoclaved sheep dung pellets at 106 colony forming units [cfu] g−1 wet weight and maintained in the laboratory either in moist soil or in a soil-free environment. In both situations, bacterial numbers increased to ca. 109 cfu g−1 of moist dung in 2 days and declined only slowly to about 108 cfu g−1 over the following 29 days at 18°C. The second experiment tested the effects of simple, carrier pre-treatments (which are likely to reduce indigenous microbial competition and increase nutrient availability) on the population dynamics of freshly inoculated P. corrugata in small pellets of two different organic plus mineral soil mixtures (cow dung and decomposed leaf litter mixed with soil). Autoclaving of cow dung led to significantly (P < 0.05) higher P. corrugata populations over a period of 21 days after inoculation compared to untreated dung. Similarly, a freshly prepared mixture of oven-dried, milled leaf litter and soil supported larger populations of P. corrugata than the same mixture that had been conditioned for 5 days (P < 0.05). In the third experiment, four species of earthworm (Aporrectodea caliginosa, A. longa, Lumbricus rubellus, L. terrestris) were fed either soil or a mixture of soil and leaf litter containing P. corrugata. High numbers (105–107 cfu g−1 fresh wt) of P. corrugata were recovered from fresh casts of all species tested.

Proposed is a method to investigate degradation of lignocelluloses by pure cultures of basidiomycetes using preserving jars with vermiculite as reservoir for water and nutrients. Bamboo samples of Gigantochloa atroviolacea and Phyllostachys pubescens and wood samples of Fagus sylvatica and Pinus sylvestris were inoculated with the brown-rot fungus Coniophora puteana and the white-rot fungus Schizophyllum commune. The fungi were cultured on vermiculite containing different amounts of tap water or malt extract solution. Mass loss of the bamboos after 32 weeks was low and did not show a remarkable influence of moisture content and nutrient addition. However, considerable degradation of Pinus sylvestris sapwood occurred by C. puteana whereby moisture and nutrients influenced aggressiveness.

Pure cultures of the Paria indoor brown-not fungi, Antrodia vaillantii, A.sinuosa, A.serialis, A.xantha and Tyromyces placenta, were studied regarding growth rate, response to temperature, copper tolerance, wood decay and mycelial interactions. Radial growth extension reached from 4-9 mm/d. All fungi were rather resistant to high temperatures. Optimum temperature was between 25 and 31°C. All withstood 1 hour at 60°C and some even 3h at 65°C. A.vaillantii showed copper tolerance up to 0.05 M Cu. Wood weight loss after 20 weeks was higher by T.placenta (35%) and A.sinuosa (33%) than by A.xantha (21%), A.serialis (16%) and A.vaillantii (14%). Dual cultures showed various inter- and intraspecific interactions and detected identity of differently coded cultures. The former Poria vaporaria Normstamm II for testing wood preservatives and the recent Poria placenta EN113 strain, FPRL280, were assumed either to be identical or at least to originate from the same individual.

Species of the Poria group causing brown rot of wood in buildings and with similar morphological appearance and biology, namely Antrodia vaillantii, A. seriadis, A. sinuosa, A. xantha, and Tyromyces placenta, were investigated by SDS polyacrylamide gel electrophoresis. Different cultures of A. vaillantii showed a species-specific protein profile separating the fungus from A. serialis, A. sinuosa and A. xantha and from T. placenta. The method also differentiated these pore fungi from the dry rot fungus Serpula lacrymans and detected misidentifications

International audience; Brown rot decay removes cellulose and hemicellulose from wood-residual lignin contributing up to 30% of forest soil carbon-and is derived from an ancestral white rot saprotrophy in which both lignin and cellulose are decomposed. Comparative and functional genomics of the "dry rot" fungus Serpula lacrymans, derived from forest ancestors, demonstrated that the evolution of both ectomycorrhizal biotrophy and brown rot saprotrophy were accompanied by reductions and losses in specific protein families, suggesting adaptation to an intercellular interaction with plant tissue. Transcriptome and proteome analysis also identified differences in wood decomposition in S. lacrymans relative to the brown rot Postia placenta. Furthermore, fungal nutritional mode diversification suggests that the boreal forest biome originated via genetic coevolution of above- and below-ground biota.

We used natural abundance stable isotope techniques to estimate carbon and nitrogen turnover rates in body tissue and mucus of earthworms. Isotope ratios of carbon (delta(13)C) and nitrogen (delta(15)N) were monitored simultaneously in body tissue and mucus for up to 101 days in feeding or fasting Lumbricus festivus kept in an artificial substrate. When the diet of the earthworms was switched from clover (C(3) plant, legume) to maize (C(4), non-legume), the new dietary delta(13)C signature manifested itself much more rapidly in the mucus than in the body tissue of the animals, causing a delta(13)C shift of about 4 per thousand in mucus and 1 per thousand in tissue after 13.5 days. Turnover of earthworm body tissue carbon, unlike that of mucus carbon, was described adequately by an exponential, single-pool model. Nitrogen turnover could not be assessed because the delta(15)N difference between sources was too small. Fasting for 56 days did not result in the expected whole-body (15)N or (13)C enrichment, but it caused a significant decrease in mucus and tissue C:N ratios and in the ratio (mucus C:N ratio):(tissue C:N ratio). We conclude that the separate analysis of body tissue and mucus has great potential for studying the ecophysiology, feeding ecology and role in elemental cycling of earthworms and other invertebrates.

Monokaryotic single-basidiospore mycelia were derived from ten dikaryon isolates (stocks) of Serpula lacrymans, and the infertility between them was investigated. The isolates originated from different localities in Europe and Australia, and were induced to fruit in the laboratory. Monokaryons produced arthropores, dikaryons showed clamp connections. The external reactions in different mating factor combinations pairings were variable. When four mating types from each stock were paired in all combinations, the pairings yielded only 442 dikaryons out of 720 possible, due to the occurrence of only 4 different A and 5 B factors in the sample. The number of different mating factors in the natural population of S. lacrymans is probably not much more, indicating a low outbreeding efficiency.

On etude l'aptitude a la degradation du bois de nouvelles souches de Serpula lacrymans monocaryotiques et dicaryotiques, ainsi que leur inhibition par le borax

Indoor wood-decay fungi cause considerable economical damage. Most of the structural damage to the indoors of buildings in Europe and North America is caused by brown-rot fungi that degrade conifer wood; white-rot fungi, which preferentially attack hardwoods, are less common. This review covers the approximately 80 basidiomycetes that commonly occur in buildings. Emphasis was placed on Serpula lacrymans, which is the most common indoor basidiomycete in central Europe. Meruliporia incrassata, the North American pendant to S. lacrymans, has also received considerable attention. In terms of indoor wood decay, moisture and temperature are the most important influences. Wood samples with a low moisture content can be degraded. High temperatures as an alternative control measure do not kill mycelia, with some species surviving in wood samples in the form of heat-resistant arthrospores at temperatures as high 95°C. For refurbishment and scientific purposes, the identity of the causal species should be known. More recently, several molecular techniques have been used to identify fungi; these results are often conflicting with those obtained by other, earlier applied methods. Sequencing of the internal transcribed spacers (ITS) of the rDNA is currently the best molecular tool. Among the other methods available, matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI TOF MS) has also been shown to be able to distinguish closely related sister taxa. For further characterization of indoor basidiomycetes, the complete sequences of the 18S, 28S rDNA and the intergenic spacers with the included 5S rDNA have been acquired for some species. If current projects involving whole funal genome sequencing are not taken into account, Antrodia vaillantii is the first basidiomycete for which the complete rDNA sequence has been deposited. The review closes with fundamentals on the prevention and control of indoor wood decay.

A simple method is described that causes basidiome formation by the dry rot fungus Serpula lacrymans in culture. S. lacrymans is incubated on malt agar plates for three to five weeks at 25°, followed by two to four weeks at 20°.

Etude de la degradation des bois de Fagus sylvatica, Populus, Picea abies et Pinus sylvestris par 57 souches bacteriennes