Xylophagous Fungi Research Articles

Promising Antifungal Activity of Cedrela fissilis Wood Extractives as Natural Biocides against Xylophagous Fungi for Wood Artwork of Cultural Heritage

Xylophagous fungi are able to thrive inside wood because they produce enzymes that can degrade it and cause significant damage. Due to this process, in the case of wood that forms part of the structure of a building or furniture, xylophagous fungi pose a serious problem that needs to be addressed, as they can compromise the integrity and durability of the wood. The aim of this work was to obtain extractives from Cedrela fissilis wood in order to conduct a preliminary evaluation of their antifungal activity against xylophagous fungi Trametes trogii (white rot), Pycnoporus sanguineus (white rot), and Chaetomium globosum (soft rot). The antifungal activity of the extractives was evaluated against these xylophagous fungi through tests of growth fungal colonies with the extractives in Petri dishes. All the evaluated extractives showed antifungal activity against all the fungi tested, demonstrating their potential use as natural biocides for wood artwork of Cultural Heritage.

Angiosperm fossil woods from the Upper Cretaceous (Cardiel Formation) of Argentinean Patagonia

Abstract We describe nine angiosperm fossil woods from sediments of the Cardiel Formation (Upper Cretaceous) near the Cardiel Lake, Santa Cruz Province, Argentinian Patagonia. On the basis of the characteristics of the anatomy, the specimens were placed in three fossil species: Weinmannioxylon trichospermoides related to the Cunoniaceae, Burseroxylon panzai sp. nov. possibly related to the Anacardiaceae or Burseraceae, and a new taxon with unknown affinity, Tortorellixylon oligoporosum gen. et sp. nov. Angiosperms are 15% of the assemblage and conifers 85%, which is consistent with previous studies of fossil woods from the Late Cretaceous of Patagonia. Most specimens show poorly distinct growth ring boundaries that suggest a weakly marked annual seasonality during the deposition of the Cardiel Formation. In addition, the specimens’ size and the rings’ curvature are consistent with large trees. Decay patterns similar to those produced by modern xylophagous fungi are also recognized in most specimens. The identification of three species in an assemblage of nine fossil woods suggests a significant taxonomic richness of angiosperms, and the taxonomic composition suggests a Late Cretaceous age for the Cardiel Formation (probably Campanian–Maastrichtian). These new records allow a better understanding of the composition of the fossil forests of the Late Cretaceous of Patagonia, in which the tree canopy was apparently dominated by conifers.

Silver Nanoparticles and Chitosan Oligomers Composites as Poplar Wood Protective Treatments against Wood-Decay Fungi and Termites

This study focuses on Populus ×euramericana (Dode) Guinier, a globally distributed fast-growing tree. Despite its valuable wood, it exhibits low durability. The aim of this study was to assess the efficacy of a binary composite comprising silver nanoparticles (AgNPs) and chitosan oligomers (COS) in protecting P. ×euramericana ‘I-214’ wood against degradation caused by xylophagous fungi and termites through vacuum-pressure impregnation. The test material was carefully selected and conditioned following the guidelines of EN 350:2016, and impregnation was carried out in accordance with EN 113-1:2021. Five concentrations of AgNPs–COS composites were utilized. Biodeterioration resistance was evaluated based on EN 350:2016 for white (Trametes versicolor (L.) Lloyd) and brown (Coniophora puteana (Schumach.) P.Karst.) rot fungi, and EN 117:2012 for subterranean termites (Reticulitermis grassei Clément). The durability class and use class were assigned following EN 350:2016 and EN 335:2013, respectively. In comparison to the untreated control, the binary solution at its highest concentration (AgNPs 4 ppm + COS 20 g·L−1) demonstrated a notable reduction in weight loss, decreasing from 41.96 ± 4.49% to 30.15 ± 3.08% for white-rot fungi and from 41.93 ± 4.33% to 27.22 ± 0.66% for brown rot fungi. Furthermore, the observed termite infestation shifted from “heavy” to “attempted attack”, resulting in a decrease in the survival rate from 53.98 ± 10.40% to 26.62 ± 8.63%. Consequently, the durability classification of P. ×euramericana I-214 witnessed an enhancement from “Not durable” to “Slightly” and “Moderately durable” concerning decay fungi and termites, respectively. These findings expand the potential applications of this wood and substantiate the advantages of employing this environmentally friendly treatment.

Natural durability of timber species exposed to xylophagous fungi in southern Durango, Mexico.

Wood is a natural resource used for construction and the manufacture of many products. This material is exposed to damage due to biotic and abiotic factors. An important biotic factor is wood-degrading fungi that generate large economic losses. The objectives of this study were to determine the effect of xylophagous fungi (Coniophora puteana and Trametes versicolor) on the natural durability of six timber species in southern Durango, Mexico, and to establish differences between fungal effects on each tree species. Samples of Pinus durangensis, P. cooperi, P. strobiformis, Juniperus deppeana, Quercus sideroxyla, and Alnus acuminata were exposed to fungi for 4 months under laboratory conditions according to European Standard EN350-1. Samples of Fagus sylvatica were used as control. Durability was determined as the percentage of wood mass loss for each species. Welch ANOVA tests were performed to establish differences among tree species. Welch t-tests were used to prove loss mass differences between fungi for each tree species. The most resistant species to C. puteana were P. durangensis, J. deppeana, P. cooperi and P. strobiformis, showing mean mass losses lower than 8.08%. The most resistant species to T. versicolor were J. deppeana, P. strobiformis and P. durangensis (mean mass losses lower than 7.39%). Pinus strobiformis and Q. sideroxyla were more susceptible to C. puteana effect; in contrast, P. durangensis and P. cooperi showed more damage due to T. versicolor degradation. Woods of P. durangensis, P. cooperi, P. strobiformis and Juniperus deppeana are well adapted to infection by these xylophagous fungi and are therefore highly recommended for commercial use in southern Durango, Mexico.

Resistance of Untreated and Torrefied Medium-Density Fiberboard (MDF) Residues to Xylophage Fungi

The manufacture of wood panels generates a large amount of waste. This material can be an option for renewable energy generation. However, long-term storage, exposure to moisture and contact of these panels with the soil facilitate colonization by xylophagous organisms. Torrefaction, a heat treatment between 200 and 300 °C in an oxygen-free atmosphere, is a process that decreases hygroscopicity while increasing carbon content, energy efficiency and resistance to fungal attack. This work aimed to evaluate the resistance of MDF panel residues. The MDF panels were produced using eucalyptus wood and bonded with thermosetting synthetic resin, under high temperature and pressure, torrefied at 300 °C for 20, 30 and 40 min and exposed to the xylophagous fungi of the white rot, Irpex lacteus (Fr.) Fr. (1828) and Trametes versicolor, and that of the brown rot, Postia placenta. After the 12-week evaluation period under fungal exposure, the mass loss of the samples attacked by T. versicolor and P. placenta was similar between treatments, except the MDF untreated, which had greater mass losses from the fungus Irpex lacteus. The torrefaction process increased the material resistance to deterioration by fungi, with an inverse correlation between the torrefaction period and the mass losses by fungal attack of the MDF panel residues.

Lichen Transplantation on Polyporales Fungi. An Attempt to Verify the Compatibility after Translocation from a Hill Forest to Anthropized City Parks at Livorno (Tuscany, Italy)

The transplantation of genus Cladonia terricolous lichens on Polyporales parasitic xylophagous fungi was attempted. Three species of Cladonia (C. pyxidata, C. rangiformis, C. foliacea) have been moved (translocated) from Livorno hill woods (Tuscany, Italy) to some public Livorno parks which suffer by an excessive anthropization. After a short period (a week) of adaptation to the new environment we transplanted thirteen specimens of Cladonia lichens on four different species of Polyporales fungi (Fomitopis betulina, Phellinus torulosus, Stereum hirsutum and Ganoderma applanatum) identified on the trees of the parks. The transplants obtained good engraftment and every periodic qualitative control showed a persistent photosynthetic activity even eight months after the start. Only one transplant (on Ganoderma applanatum) failed due by the toxicity of a secretion after incision. These observations lead us to consider those experiments as a demonstration of the compatibility of the implied tissues on transplantation and also allow us to introduce the difference of the term transplantation (the insert of an organism to another) from the often-confused translocation (relocation of an organism in different habitat). Future checks will indicate how and for how long this artificial association complex might persist.

Mechanical Properties of Three Bamboo Species: Effect of External Climatic Conditions and Fungal Infestation in Laboratory Conditions

Bamboo is a material with good tensile and flexural resistance. As a construction material with structural capacity, using bamboo implies considerable environmental advantages in relation to other typical materials such as steel or concrete. For its correct implementation, it is necessary to define its mechanical properties and durability. Bamboo is susceptible to degradation due to the lack of natural toxins and thin walls, which means that shallow decomposition processes can imply appreciable reductions in its mechanical capacity. The main degrading agents considered in this study were beetles, termites, and xylophagous fungi. The aim of this study was to analyze the durability of three different species: DS, PA, and AA. Durability and mechanical tests results after 6 months of exposure to biotic and abiotic agents were compared with their original properties and chemical composition. In this study, durability was analyzed in two ways. Firstly, the loss of mass due to fungal infection was investigated. The results obtained were based on the standard EN 113 using the fungus CP. Secondly, bending and compressive strength was evaluated after a durability test according to the standard EN 335:2013 for the CU3.1 use class after a 6 month period in the city of Donostia/San Sebastian, Spain. The DS and AA varieties were rated as very durable CD1, while the PA variety is durable CD2, thus proving to be an attractive material for construction.

Durability Evaluation of New Composite Materials for the Construction of Beehives

Given the current situation we face regarding climate change, one of the greatest and most critical concerns is related to the reduction in the bee population. This population largely depends on beekeeping production units around the world. However, these production units also face great challenges in the construction of beehives, as pine word generally deteriorates within a period of five years or less. This relatively rapid deterioration has both economic and environmental repercussions, which may affect the economic sustainability of the beekeeping system. The objective of this research was the production and subsequent evaluation of the durability of alternative composite materials that can be used in beehive construction. The materials are based on high-density polyethylene and agro-industrial residues (fique fiber, banana fiber, and goose feathers) from the Boyacá region of Colombia. The composite materials studied in the present study were exposed to xylophagous fungi for 90 days, at constant humidity and under controlled temperature conditions that are conducive to fungi proliferation. The results showed that composite materials that include fique fibers are the most promising substitute for wood in the construction of beehives. Indeed, these materials were shown to be 80% more resistant to pathogen attack and durable weight loss than pine wood. These durability results may be of great importance for future implementation in beekeeping production units. They have the potential to impact not only the sustainable development of rural communities, but also to make a great ecological contribution by reducing the need to cut down trees while maintaining the health of beehives.

Antifungal Activity of Datura stramonium L. Extractives against Xylophagous Fungi

Some plants have great resistance against herbivores, invertebrates, insects, bacteria, and fungi. This resistance is mostly present in plants containing alkaloids, which are the substances responsible for giving them defensive properties. The genus Datura contains tropane alkaloids and all plants from this genus have defensive properties. In this work, we report the toxic effect against fungi of Datura stramonium extracts, obtained by the Petri dish method. The extraction solvents were water, ethanol, 2-propanol, n-butanol, propanone, butanone, 3-methyl-2-pentanone, dichloromethane, xylene, and toluene. The test fungi were Trametes versicolor (L. ex. Fr) Pilát and Rhodonia placenta (Fr.) Niemelä, K.H.Larss. & Schigel. It was found that water, butanone, and toluene extracts promoted mycelial growth, xylene extracts neither inhibited nor promoted mycelial growth, while the other extracts slightly inhibited the growth of these fungi.

Effect of silica bionanoparticles obtained from rice husk for the treatment of wood of Pinus elliottii

Renewable products can ensure environmental sustainability, human health, and reduce the use of traditional products that have toxic compounds in their formulation. Therefore, the research aimed to evaluate the biological resistance of Pinus elliottii wood against xylophagous fungi and termites through impregnation with silica bioparticles (SiO2) obtained from rice husks. To obtain the silica, the material underwent chemical treatment, two cycles of acid leaching with hydrochloric acid, and heat treatment at 500 °C, 550 °C or 600 °C. The purity of the silica obtained was characterized by X-ray fluorescence technique (XRF), and the mean particle size by scanning electron microscopy (SEM). SiO2 was applied to the specimens at concentrations of 0.5%, 1.0%, and 2.0%, and the impregnated samples were subjected to tests with brown rot fungi (Gloeophyllum trabeum, Rhodonia placenta and Neolentinus lepideus), soft rot (taken from natural forest soil) and xylophagous termites (Nasutitermes corniger and Cryptotermes brevis). The thermal treatments promoted the obtainment of high purity bioparticles, with value of approximately 90% and diameter of 263.7 nm. In the termite test, the smallest loss of mass and damage were for the impregnated samples. Termite mortality increased with the concentration of solutions. SiO2 was not effective against xylophagous fungi, with no difference between treatments and controls, indicating that resistance was inherent in the wood itself.

Colour of polyurethane foams filled with wood and wood derivatives exposed to two xylophagous fungi

This study addresses changes in aesthetical features of bio-based polyurethane (PU) foams filled with four forest-based particles (namely wood flour, wood bark, kraft lignin, and paper sludge), which were decayed by two wood-rot fungi. White-rot and brown-rot fungi were inoculated on these foams and further characterization results were obtained using colourimetric parameters measured according to the CIELab method. The fungi penetrated into both intra and intercellular spaces into the PU foams, although it neither changed the foam weight nor chemically interacted with the polymer cell wall. These fungi changed overall the appearance of the foams, which indicates that a protective strategy against these microorganisms may be of interest, especially for foam parts used in contact with wood products. The neat PU presented smaller colour stability if compared to the filled foams. Among the fillers, powdered kraft lignin stood out and can be indicated to produce valuable darkened PU parts with stable colour patterns.

Oil in Water Nanoemulsions Loaded with Tebuconazole for Populus Wood Protection against White- and Brown-Rot Fungi

Eugenol in water nanoemulsions loaded with tebuconazole appear as a very promising alternative formulations for wood protection against xylophagous fungi that are the main species responsible for different rots in wood structures. The dispersions as prepared and upon dilution (impregnation mixtures) were characterized by the apparent hydrodynamic diameter distribution of the oil droplets loaded with tebuconazole and their long-term stability. The impregnation mixtures were applied on wood of Populus canadensis I-214 clone by using a pressure-vacuum system, and the effectiveness against fungal degradation by Gloeophyllum sepiarium and Pycnoporus sanguineus fungi was determined. The retention of tebuconazole in wood was about 40% of the amount contained in the impregnation mixtures. The results showed that the impregnation process leads to a long-term antifungal protection to the wood, with the mass loss after 16 weeks being reduced more than 10 times in relation to the control (untreated poplar wood) and the reference wood (untreated beech wood).

Resistência de espécies arbóreas tropicais à ação de <i>Ganoderma philippii</i>

A resistência da madeira a fungos xilófagos é uma característica desejável em madeiras comerciais e nas empregadas na arborização urbana. Isso porque a ação desses fungos pode levar à perda das propriedades físicas, redução da resistência mecânica e durabilidade da madeira. Entretanto, pouco se sabe sobre a resistência de madeiras tropicais a fungos apodrecedores. Nesse contexto, este trabalho teve como objetivo avaliar a resistência natural da madeira de 28 espécies arbóreas tropicais submetidas à ação de Ganoderma philippii, através da análise da perda de massa obtida em um ensaio in vitro. Segundo os critérios de classificação de resistência a fungos da ASTM D2017 (2005), a maioria das espécies foi considerada altamente resistente, exceto Amburana cearensis, Pterocarpus rohrii, Joannesia princeps e Basiloxylon brasiliensis consideradas resistentes. A comparação dos valores de perda de massa obtidos entre todas as espécies arbóreas, após a ação de Ganoderma philippii, demonstrou que Joannesia princeps, Amburana cearensis, Pterocarpus rohrii, Basiloxylon brasiliensis, Barnebydendron riedelii, Parkia pendula, Cariniana legalis, Copaifera langsdorffii, Terminalia mameluco, Spondias venulosa, Astronium concinnum e Zeyheria tuberculosa tiveram perda de massa estatisticamente maior que as demais espécies.

Antifungal activity of Cinnamomum zeylanicum bark natural extract subjected to xylophagous fungi

The search for natural wood preservatives is becoming increasingly evident due to industrial preservatives presenting several environmental restrictions, such as soil, water and ecosystems contamination. Therefore, the objective of the present study is to evaluate the antifungal activity of Cinnamomum zeylanicum bark natural extract subjected to rotting fungi. In order to obtain the aqueous extract, two methods were performed with different concentrations, 50 and 100 g L-1, using Pycnoporus sanguineus e Gloeophyllum trabeum, mycelium. In the first, we kept the C. Zeylanicum bark with distilled water for 1 h in water bath and, in the second, the same concentrations were used, however, this was kept in a recipient for 24 h. Then, the extract was subjected to sterilization along with the BDA medium in autoclave at 120ºC for 20 min, they were then put in petri dishes for later evaluation of the mycelium root growth compared with the control. The fungi Pycnoporus sanguineus presented higher fungal activity, obtaining total inhibition of all treatments and extract concentrations, however, for the fungi Gloeophyllum trabeum, the 100 g L-1 concentration warmed in water bath obtained a better result than the others. Therefore, it can be concluded that the Cinnamomum zeylanicum aqueous extract presented inhibitory potential. Considering this, we suggest that more studies with this thematic should be carried out, seeking to discover new alternatives for wood preservatives that are less damaging to the environment and to mankind.

Susceptibility of Populus x euramericana ‘I-214’ of Spanish origin to xylophagous attacks: durability tests for its possible inclusion in European standard

Aim of study: to assess the natural durability of Populus x euramericana ‘I-214’ against xylophagous fungi and termites, and to carry out a macro-microscopic analysis of the alterations caused by each xylophagous agent in order to get the necessary information for its possible inclusion in existing European standards.Area of study: A 20-years-old commercial plantation Populus x euramericana‘I-214’ located in Quintanilla de Sollamas (42° 36′ 00″N - 05° 49′ 00″ W), Spanish community of Castile-LeonMaterial and methods: material sampling and selection was carried out following EN 350:2017 for commercial sawn timber. Poplar resistance to xylophagous basidiomycete, soft rot fungi and subterranean termites was determined according to CEN/TS 15083-1:2005, CEN/TS 15083-2:2005 and EN 117:2012, respectively. The durability and use classes were estimated according to EN 350:2016 and EN 335:2013, respectively. The anatomical studies were carried out with Optical and Scanning Electron Microscope. Material characterization was carried out by reference to Anagnost (1998) and Schwarze (2007).Main results: ‘I-214’ poplar wood proved to be “Not-durable” to the action of basidiomycetes, soft rot fungi and termites, use classes 1-2, and showed macro-microscopic evidence of these types of decay.Research highlights: the information obtained in this study would allow the inclusion of clone I-214 in the standard EN 350 and its explicit classification within it.Keywords: wood-decay fungi; termites; EN 350.Abbreviations used: TM: test material; RM: reference material; RH: relative humidity; ML: mass loss; mi: initial dry mass; mf: final dry mass; DC: durability class; OM: Optical Microscope; SEM: Scanning Electron Microscope; TS: transverse section samples; LS: longitudinal section samples; CI: robust confidence intervals; F: fibre; V: vessel; h: hole; t: erosion trough; R: radial parenchyma cell; ep: erosion pitting; Fc: fungal colonization; fr: fracture; c: cavity; b: bore hole; m: mycelium.

Resistance of in natura and torrefied wood chips to xylophage fungi

The diversity of fungi allows for their colonisation in different environments, including wood destined for power generation, with an ability to degrade or hinder its use. Torrefaction or pre-carbonisation, a low oxygenation heat treatment with temperatures between 200 and 300 °C, accumulates carbon and lignin, decreases hygroscopicity, increases energy efficiency and reduces the wood attractiveness to xylophagous microorganisms. This work aimed to study the resistance of Eucalyptus urophylla wood chips, submitted to torrefaction temperatures of 180, 220 and 260 °C for 20 minutes, to xylophagous fungi, according to the ASTM D-2017 method (2005). The white rot fungi Phanerochaete chrysosporium, Pleurotus ostreatus and Trametes versicolor and the brown rot fungus Gloeophyllum trabeum were used. After 12 weeks of exposure, the mass losses of wood samples in natura and torrified at 180 °C attacked by Pleurotus ostreatus and Trametes versicolor was higher. Torrefaction increased the resistance to fungi; the treatment at 260 °C was the most efficient with lower mass losses caused by fungi attacks and, consequently, greater resistance to the fungi tested.

Evidence to wood biodeterioration of tropical species revealed by non-destructive techniques

The wood biodeterioration process is one of the symptoms produced by biotic agents that affect the biomechanics of urban trees and reduce their useful life and environmental services. This process is mainly studied through methods that are time-consuming or destructive and provide little information regarding the degradation process at the cellular scale. Based on a non-destructive study of five tropical urban trees: Poincianella pluviosa (sibipiruna), Pterocarpus rhorii (aldrago), Rhamnidium elaeocarpum (saguaraji), Trichilia clausenii (Catiguá) and Lafoensia glyptocarpa (mirindiba rosa); the wood decaying zone, by xylophagous fungi, was analized. The trunk-wood samples containing the decaying zone were extracted with metal probes. Their microscopic anatomical structures were characterized and their microdensity and chemical composition analyzed by X-ray densitometry and X-ray fluorescence, respectively. Degraded cell wall fiber and vessels obstructed by mycelial mass were observed in wood decay zones. The presence of wood compartmentalized by the formation of extractive deposits was also observed, as a possible resistance mechanism varying among species. Likewise, phosphorus (P), calcium (Ca), calcium/manganese molar ratio and wood density increase were observed in barrier zones, while iron (Fe) was related to the decay zone. Altogether, the present study show for detailed evaluation of the wood biodeterioration process at the microscopic scale. The potential of non-destructive techniques for application in the physiological analysis of trees was also demonstrated.

Granulobasidium vellereum (Ellis &Cragin) Jülich, a promising biological control agent

Studies involving biological control of wood decay fungi and pests in forest areas are scarce. The basidiomycete Granulobasidium vellereum (Ellis & Cragin) Jülich has been isolated as wood endophyte from London Plane trees (Platanus acerifolia (Ait.) Willd). This basidiomycete produces a variety of sesquiterpenes with antifungal activity. In this study we evaluated the potential activity of G. vellereum against wood decay fungi and fungi associated with the ambrosia beetle Megaplatypus mutatus Chapuis, an important forest pest in Populus sp. A combination of in vitro assays was made, in cultures and on wood blocks. Granulobasidium vellereum’s Volatile Organic Compounds (FVOCs) were characterized and their potential role in biocontrol was assessed. Granulobasidium vellereum did not cause a significant loss of weight on P. acerifolia and Populus wood and inhibited the growth of the target fungi, mainly when inoculated first. Up to nineteen volatile compounds were determined in G. vellereum strains. The growth of all target fungi was inhibited by FVOCs and in some cases the morphology of the fungi was altered. These results indicate that G. vellereum can be used as a Biological Control Agent (BCA) of xylophagous fungi and fungi related to forest pests. Further investigations should focus on developing application strategies for M. mutatus management.

Natural resistance of four Amazon woods submitted to xylophagous fungal infection under laboratory conditions

The present study aimed to assess the natural resistance of four Amazon tropical wood species, used in the production of sawn timber, against infection with xylophagous fungi. Apuleia leiocarpa (amarelão), Dinizia excelsa (angelim vermelho), Vochysia maxima (quaruba), and Bagassa guianensis (tatajuba) were selected to perform the accelerated laboratory test. These species were exposed to white rot xylophagous fungi Pycnoporus sanguineus, Phanerochaete chrysosporium and Schizophyllum commune, and to the brown rot fungus Gloeophyllum abietinum. The laboratory test was performed following the methodology and classification of the natural resistance of wood according to ASTM D2017-86 (American Society for Testing Materials). All species were classified as highly resistant to fungal attack; however, V. maxima lost the highest percentage of weight. Therefore, we recommend that D. excelsa, A. leiocarpa, and B. guianensis be used in the production of sawn timber since they exhibited lower weight loss in the presence of all the fungi tested during a period of 12 weeks.

The Frequency of Xylophagous Fungi in a Plum Plantation from Reghin Area

The main purpose of the study was to observe the frequency of the wood decay fungi in plum plantations and also to identify the species of xylophagous fungi that grow on plum trees. The plum varieties used in the experiment were Anna Spath, De BistriE›a, Stanley and Silvia on which the lesions in the trees were counted and the infected lesions were monitored in four plantations. The monitored plantation was affected by two species of wood decaying fungi, identified as Phellinus igniarius and Stereum hirsutum, the frequency of the Stereum hirsutum specie being higher compared with Phelinus igniarius.