Primary cavity excavators, such as woodpeckers, are ecosystem engineers in many systems. Associations between cavity excavators and fungi have long been hypothesized to facilitate cavity excavation, ...but these relationships have not been experimentally verified. Fungi may help excavators by softening wood, while excavators may facilitate fungal dispersal. Here we demonstrate that excavators facilitate fungal dispersal and thus we report the first experimental evidence of a symbiosis between fungi and a cavity excavator, the red-cockaded woodpecker (RCW, Picoides borealis). Swab samples of birds showed that RCWs carry fungal communities similar to those found in their completed excavations. A 26-month field experiment using human-made aseptically drilled excavations in live trees, half of which were inaccessible to RCWs, demonstrated that RCWs directly alter fungal colonization and community composition. Experimental excavations that were accessible to RCWs contained fungal communities similar to natural RCW excavations, whereas inaccessible experimental excavations contained significantly different fungal communities. Our work demonstrates a complex symbiosis between cavity excavators and communities of fungi, with implications for forest ecology, wildlife management, and conservation.
Mycoheterotrophic plants (MHPs) are leafless, achlorophyllous, and completely dependent on mycorrhizal fungi for their carbon supply. Mycorrhizal symbiosis is a mutualistic association with fungi ...that is undertaken by the majority of land plants, but mycoheterotrophy represents a breakdown of this mutualism in that plants parasitize fungi. Most MHPs are associated with fungi that are mycorrhizal with autotrophic plants, such as arbuscular mycorrhizal (AM) or ectomycorrhizal (ECM) fungi. Although these MHPs gain carbon via the common mycorrhizal network that links the surrounding autotrophic plants, some mycoheterotrophic lineages are associated with saprotrophic (SAP) fungi, which are free-living and decompose leaf litter and wood materials. Such MHPs are dependent on the forest carbon cycle, which involves the decomposition of wood debris and leaf litter, and have a unique biology and evolutionary history. MHPs associated with SAP fungi (SAP-MHPs) have to date been found only in the Orchidaceae and likely evolved independently at least nine times within that family. Phylogenetically divergent SAP Basidiomycota, mostly Agaricales but also Hymenochaetales, Polyporales, and others, are involved in mycoheterotrophy. The fungal specificity of SAP-MHPs varies from a highly specific association with a single fungal species to a broad range of interactions with multiple fungal orders. Establishment of symbiotic culture systems is indispensable for understanding the mechanisms underlying plant–fungus interactions and the conservation of MHPs. Symbiotic culture systems have been established for many SAP-MHP species as a pure culture of free-living SAP fungi is easier than that of biotrophic AM or ECM fungi. Culturable SAP-MHPs are useful research materials and will contribute to the advancement of plant science.
Fungi are an alternative source to animal-based chitin. In fungi, chitin fibrils are strongly interconnected and bound with glucans that justify the unique matrix. The present study aimed to extract ...chitin and glucans from the mycelium of several wood decay fungal strains in order to obtain flexible materials and to check correlations between chitin content and the mechanical properties of these materials. Five strains were chosen in consideration of their different cell wall chemical composition (high content of α-glucans, β-glucans or chitin) to evaluate how these differences could influence the mechanical and chemical characteristics of the material. The fungal strains were cultivated in liquid-submerged dynamic fermentation (both flasks and bioreactor). Chitin and glucans were crosslinked with acetic acid and plasticized with glycerol to obtain flexible sheets. Abortiporus biennis, Fomitopsis iberica and Stereum hirsutum strains were found to adapt to produce material with adequate flexibility. The obtained materials were characterized by Thermogravimetric analysis (TGA) for the understanding of the material composition. The material obtained from each species was mechanically tested in terms of tear strength, elongation at break, and Young's modulus.
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•Preparation of elastomeric leather-like material derived from fungi.•Improvement of the fungi cultivation technique by using bioreactors.•A post-processing technique was developed to increase the elastomeric properties.•Understanding the role of different biopolymers content to serve as elastomers.•Reduction of the environmental impact of the leather industry by avoiding breeding and killing animals and toxic industrial processes like tanning.
In esca disease affecting grapevines,
Phaeomoniella chlamydospora
and
Phaeoacremonium minimum
colonize the woody parts of the trunks and arms, where they obtain nutrition from xylem sap and, ...potentially, from residues resulting from the enzymatic breakdown of lignified cell walls, particularly osidic residues. We quantified the secretion of lignin peroxidase, manganese peroxidase and laccase by these fungi in woody tissues of selectively infected cuttings using immunolabeling and transmission electron microscopy. Our results indicated that the detection of these enzymes was generally higher in tissues infected with
Phaeoacremonium minimum
. These data were confirmed through immunodetection of enzymes secreted by hyphae of fungi grown in vitro. Additionally, we observed that the supply of various carbohydrates (mono, di, tri and tetrasaccharides and polymers) differentially influenced fungal growth and polypeptide secretion. Since some secreted polypeptides display detrimental effects on grapevine cells, these results raise the question of whether the carbohydrate environment could be a factor affecting the aggressiveness of these pathogens.
In this study, we focused on the isolation and structural characterization of polysaccharides from a basidiocarp of polypore fungus
. Polysaccharide fractions were obtained by successive extractions ...with cold water at room temperature (20 °C), hot water under reflux (100 °C), and a solution of 1 mol L
sodium hydroxide. The purity of all fractions was controlled mainly by Fourier transform infrared (FTIR) spectroscopy, and their composition and structure were characterized by organic elemental analysis; neutral sugar and methylation analyses by gas chromatography equipped with flame ionization detector (GC/FID) and mass spectrometry detector (GC/MS), respectively; and by correlation nuclear magnetic resonance (NMR) spectroscopy. The aqueous extracts contained two main polysaccharides identified as a branched
-2-
-d-mannosyl-(1→6)-
-d-galactan and a highly branched (1→3)(1→4)(1→6)-
-d-glucan. Mannogalactan predominated in the cold water extract, and
-d-glucan was the main product of the hot water extract. The hot water soluble fraction was further separated by preparative anion exchange chromatography into three sub-fractions; two of them were identified as branched
-d-glucans with a structure similar to the corresponding polysaccharide of the original fraction. The alkaline extract contained a linear (1→3)-
-d-glucan and a weakly branched (1→3)-
-d-glucan having terminal
-d-glucosyl residues attached to
-6 of the backbone. The insoluble part after all extractions was identified as a polysaccharide complex containing chitin and
-d-glucans.
Mycelium-based insulation materials made from lignocellulosic resources have the potential to replace petroleum-based foams. In this study, desilicated wheat straw was inoculated with Pleurotus ...ostreatus (PO) and Ganoderma lucidum (GL) fungi and incubated for 10, 20, and 30 days to produce mycelium-based insulation boards. The process of extracting silica from wheat stalks was conducted using a 1% sodium hydroxide (NaOH) solution prior to the production of mycelium-based insulation boards. Density, water absorption, thickness swelling, modulus of rupture, modulus of elasticity, tensile strength perpendicular to the surface (Internal bonding test), and compressive strength of the mycelium insulation boards were measured. The results showed that mycelium-based insulation boards produced with GL had better physical and mechanical properties than those produced with PO. Furthermore, pretreatment of wheat straw with 1% NaOH improved the mechanical properties of the insulation boards produced.
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•Synthesized gemini compounds display effective tensioactive properties.•Their antifungal activities are comparable to commercial products.•New gemini succeeded in turning wood highly ...resistant against fungal degradation.•Ecotoxicity assays show less environmental impact using this new preservative.
Three gemini compounds were synthesized and characterized in the search of an alternative eco-friendly wood preservative. Synthesis was carried out from N,N-dimethylamines and 2-O-acetyl-1,3- dichloropropane as linker molecule. All the synthesized molecules were adequately purified and characterized by TLC, GC, FT-IR and NMR. Their tensioactive properties were determined. All three efficiently lowered the surface tension in aqueous solutions with critical micelle concentrations ranging from 0.53 to 1.34mM. Their antifungal activities were evaluated from a broth dilution test against four yeasts and two filamentous fungi and were compared to commercially available references: Fluconazole and TCMTB (2-thiocyanomethylthiobenzothiazole). All gemini compounds displayed good antifungal activity; particularly, the gemini derived from N,N-dimethyldodecylamine, with even better performance than Fluconazole against Saccharomyces cerevisiae, Aspergillus niger and Alternaria sp., and than TCMTB against the last one. The environmental impact of the gemini compound that showed the highest antifungal activity was analyzed through ecotoxicity tests, using Chlorella vulgaris and Daphnia magna as model organisms. It was several orders of magnitude less toxic than TCMTB. Finally, wood preservation efficacy studies were carried out on pine (Pinus ponderosa) samples. Results demonstrated accomplished resistance against brown rot fungi, comparable to a widespread commercial hydrosoluble preservative.
One of the most important biological factors that damage wood materials are wood-decay fungi (WDF). Chemical preservatives have traditionally been the most effective method for controlling WDF. ...However, due to environmental pressures, scientists are working on alternative protection methods. The aim of this study was to investigate the potential of some antagonistic fungi against wood-decay fungi as a biological control agent (BCA). For this purpose, the antagonistic effects of
Trichoderma harzianum, Trichoderma viride, Aspergillus niger
, and
Penicillium brevicompactum
fungi were investigated against the
Trametes versicolor, Trametes hirsuta, Stereum hirsutum, Coniophora puteana, Neolentinus lepideus
, and
Postia placenta
species of wood-decay Basidiomycetes fungi. In the study, firstly, inhibition rates were determined by comparing dual culture tests on agar medium, and then the performance of BCAs was compared by performing decay tests on wood blocks. As a result of the study, it was determined that the species belonging to the genus
Trichoderma
showed a very effective performance on WDF, increased the inhibition rate to 76–99%, and reduced the weight loss to 1.9–5.8%. Considering the inhibition rates, it was determined that the most effective rate of the BCAs was on
P. placenta
and the least on
S. hirsutum
species. According to the results obtained, it has been determined that some BCAs were very effective biological control agents of rot fungi on agar and wood blocks in vitro. However, in order to more clearly determine the effectiveness of BCAs in practice, this study, which was carried out in the laboratory environment, should be supported by tests performed in contact with the external field and soil.
Purpose
Wood decay fungi are the only forms of life capable of degrading wood to its initial constituents, greatly contributing to the soil ecosystem. This study summarizes the current research ...status and development characteristics of global wood decay fungi research, in order to better understand their role in soils.
Methods
A bibliometric analysis was applied to the literature from 1913 to 2020, based on data from the Web of Science (WOS) Core Collection. For this, various bibliometric analysis methods, R (Biblioshiny package), and VOSviewer were applied.
Results
A total of 8089 documents in this field were identified in the WOS Core Collection. The annual number of publications tended to increase, with exponential growth after 2008. Researchers in this field were mainly concentrated in North Europe, the USA, and China. Biotechnology, applied microbiology, environmental sciences, and microbiology were the most popular WOS categories.
Bioresource Technology
and
Applied Environmental Microbiology
were the top two journals with the most citations. The top three authors with the most published papers were Dai YC, Martinez AT, and Cui BK. Co-occurrence analysis of author keywords identified six clusters, mainly divided into three categories: the classification and diversity, the degradation mechanisms, and the ecological functions of wood decay fungi. Clustering results further showed that the lignin degradation process and the application of wood decay fungi in industrial production and soil contamination remediation are current research hotspots.
Conclusions
We present a comprehensive and systematic overview of research related to wood decay fungi and provide a deep perspective to understand the associated research progress. This is important for facilitating the development of a profound understanding of the contribution of wood decay fungi to soil systems and the degradation of soil contaminants.
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