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Research on reducing the movement of pests on wood products has led to several options for safer trade including heat treatment of wood to mitigate pests. In this study, pathogenic organisms commonly regulated in the trade of forest products were tested to determine the minimum heat dose (temperature and time) required to cause mortality. The mycelial stage of tree pathogens, Heterobasidion occidentale, Grosmannia clavigera, Bretziella fagacearum, Phytophthora cinnamomi, P. lateralis, P. ramorum and P. xmultiformis, which may be found in untreated wood products, were tested in vitro using the Humble water bath with parameters simulating the rate of heat applied to wood in a commercial kiln. RNA detection using reverse transcription real-time PCR was used to validate pathogen mortality following treatment for: P. ramorum, P. lateralis, P. cinnamomi, P. xmultiformis and G. clavigera. The lethal temperature for all pathogens ranged from 44 to 50°C for a 30-min treatment duration. Using this method to evaluate heat treatment for other forest product pests is recommended to accurately identify the minimum dose required to support phytosanitary trade. With more data potentially lower heat treatment applications may be recommended under specific conditions to produce more efficient and economical heat treatment schedules and reduce environmental impacts. [ABSTRACT FROM AUTHOR]

Research on reducing the movement of pests on wood products has led to several options for safer trade including heat treatment of wood to mitigate pests. In this study, pathogenic organisms commonly regulated in the trade of forest products were tested to determine the minimum heat dose (temperature and time) required to cause mortality. The mycelial stage of tree pathogens, Heterobasidion occidentale, Grosmannia clavigera, Bretziella fagacearum, Phytophthora cinnamomi, P. lateralis, P. ramorum and P. xmultiformis, which may be found in untreated wood products, were tested in vitro using the Humble water bath with parameters simulating the rate of heat applied to wood in a commercial kiln. RNA detection using reverse transcription real-time PCR was used to validate pathogen mortality following treatment for: P. ramorum, P. lateralis, P. cinnamomi, P. xmultiformis and G. clavigera. The lethal temperature for all pathogens ranged from 44 to 50°C for a 30-min treatment duration. Using this method to evaluate heat treatment for other forest product pests is recommended to accurately identify the minimum dose required to support phytosanitary trade. With more data potentially lower heat treatment applications may be recommended under specific conditions to produce more efficient and economical heat treatment schedules and reduce environmental impacts.

This study considered the mechanical properties of primary blue-stained sapwood of Norway spruce infested by the bark beetle Ips typographus. Nineteen stems from Stammerberg (ZH, Switzerland) were harvested in three different seasons and after different periods of bark beetle outbreaks. Density, Brinell hardness including elastic recovery after load, and key strength properties were tested on blue-stained wood and non-infected controls. Differences in mechanical properties were analysed according to the stand and storage time of the stems after the bark beetle attack. Spruce harvested at a late stage after the bark beetle attack (2–3 months) showed a clear reduction in impact bending strength, a significant loss in surface elastic recovery after indentation during Brinell hardness test, and a striking number of specimens with brittle fracture behaviour during Three-Point-Bending. Light microscopy and the results of the mechanical tests give clear evidence to suggest that wood-degrading fungi are already active in addition to the sap-staining fungi. Especially after larger outbreaks of bark beetles, it must be assumed that sapwood of Norway spruce does not only show the typical blue stain, but also incipient stages of wood degradation by wood-degrading fungi. [ABSTRACT FROM AUTHOR]

By damaging bark, mechanized harvesting deprives wood of its natural mechanical barrier. This study concerns the effect of this damage on the changes in moisture content that occur near the damaged areas of Scots pine (Pinus sylvestris L.). This study was carried out using 45 randomly selected 11 m long logged pine stems. Additionally, the effect of bark thickness on the depth of damage was measured. To determine the influence of the location of the damage and bark thickness on the wood moisture near the damaged region, wood samples were collected from two sections. The first was located one meter above the log's base, while the second was located one meter from the end of the log. Two increment cores were taken by a Pressler borer in each section: one from the damaged wood zone and the second from the undamaged wood zone. The average bark thickness one meter from the base of the log was 11.2 mm, which decreased to 1.8 mm in the samples taken one meter from the top of the log. The average depths of the damage caused by feed roller spikes in the two sections were 3.9 and 3.8 mm, respectively, indicating that there was no significant effect of bark thickness on the depth of the damage. The wood samples collected near the damaged wood zone (DW) had about 13 percent lower moisture content than those taken from the undamaged zone (UDW). This difference was statistically significant. We observed greater mean moisture content closer to the top of the log for both the samples taken near the damaged zone and the samples taken from the undamaged zone. One meter from the base of the log, the moisture content difference between the DW and UDW was 9.8 percentage points, which was statistically insignificant. By contrast, significantly lower moisture content (−16%) was observed in the DW one meter from the top of the log. [ABSTRACT FROM AUTHOR]

Wood coatings prolong the service life of wood-based products, but they are usually of synthetic origin. The aim of the present article is to reduce the fossil-based compounds in a commercial waterborne acrylic coating by CNC addition and to test its performance. The coatings were applied on European beech and Norway spruce wood in order to test durability against Gloeophyllum trabeum (brown wood rot) and Trametes versicolor (white wood rot). Artificial weathering and blue stain, contact angle, physical tests (adhesion, impact and scratch test), chemical (FTIR) and morpho-anatomical analysis (SEM) were carried out. CNC addition increased viscosity, limiting the spreading of the coating into wood pores as visible after SEM observation, which reduced coating adhesion on the substrate. CNC improved fungal resistance as seen by a reduced mass loss and FTIR spectroscopy thanks to crosslinks formation, which reduced water sorption as well. Color change was not significant, and, on the other hand, glossiness was reduced but resulted as more homogeneous than control. CNC addition gave good results also in blue stain protection. CNC improved scratch resistance, but no visible change to impact was registered. CNC has promising results in coatings depending on wood and fungal species and presence of further commercial additives (biocides). [ABSTRACT FROM AUTHOR]

By damaging bark, mechanized harvesting deprives wood of its natural mechanical barrier. This study concerns the effect of this damage on the changes in moisture content that occur near the damaged areas of Scots pine (Pinus sylvestris L.). This study was carried out using 45 randomly selected 11 m long logged pine stems. Additionally, the effect of bark thickness on the depth of damage was measured. To determine the influence of the location of the damage and bark thickness on the wood moisture near the damaged region, wood samples were collected from two sections. The first was located one meter above the log’s base, while the second was located one meter from the end of the log. Two increment cores were taken by a Pressler borer in each section: one from the damaged wood zone and the second from the undamaged wood zone. The average bark thickness one meter from the base of the log was 11.2 mm, which decreased to 1.8 mm in the samples taken one meter from the top of the log. The average depths of the damage caused by feed roller spikes in the two sections were 3.9 and 3.8 mm, respectively, indicating that there was no significant effect of bark thickness on the depth of the damage. The wood samples collected near the damaged wood zone (DW) had about 13 percent lower moisture content than those taken from the undamaged zone (UDW). This difference was statistically significant. We observed greater mean moisture content closer to the top of the log for both the samples taken near the damaged zone and the samples taken from the undamaged zone. One meter from the base of the log, the moisture content difference between the DW and UDW was 9.8 percentage points, which was statistically insignificant. By contrast, significantly lower moisture content (−16%) was observed in the DW one meter from the top of the log.

Blue staining leads to significant economic losses because of the changes it causes in the aesthetic characteristics and mechanical shock resistance of log, timber and materials in the usage area. On the other hand, it is known that the low success rate of impregnation and surface treatment in materials exposed to degradation considerably narrows down industrial usage areas of the logs. This study aims to determine the effects of blue stain degradation on manufacturing process of forest industry managements processing log and the losses caused by this. This research was conducted in a total of 9 small and medium sized lumber production managements processing scots pine log in Gümüşhane province. In this study, the size of the blue stain degradation was evaluated by calculating the total volume of the log. On the other hand, comparisons regarding blue stain degradation have been carried out between the managements that conduct productions intended for the construction and woodworking sectors. At the end of the study, it has been determined that the ratio of exposure to volumetric damages ranges between %32-84 depending on fresh wood width, log length and diameter variables in the blue stain degradation. Furthermore, it has been confirmed that statistically significant differences (p

This study investigated the effects of felling season on the discoloration of rubberwood sawn timber during conventional kiln drying. The samples were collected throughout the year 2015 to monitor the variation of free sugars and starch content in the rubberwood logs. Two batches of logs, one from the rainy season and the other from the dry season, were felled and sawn for experimentation. The findings showed that discoloration was more prominent in sawn timber obtained from logs felled during the dry season. The amount of free sugars and starch in the logs had a strong influence on the extent of discoloration in the rubberwood sawn timber during the kiln drying process. A higher amount of free sugars and starch in the logs felled during the dry season increased the incidence of blue stain on these logs. The results of this study conclusively showed that discoloration in rubberwood can be minimized by the choice of log felling season and the use of an appropriate drying technique, which will inevitably improve the aesthetic appeal of the wood.

In this research, the effect of wetwood and blue stain on the drying rate and fluid transport coefficients of poplar (P. nigra) was evaluated. For this purpose, five boards with dimensions of 150 × 35 × 45 mm were cut from wet‌ wood, normal ‌wood and stained -wood areas of freshly cut lumbers in Taleghan region and then dried to the final moisture content of 8 percent inside a laboratory dryer at temperature of 50 °C, relative humidity of 60% and air velocity of 1 m/s. Overall, drying time was 120 h. After drying, the transverse permeability and diffusion coefficients were measured. The results showed that the wetwood had no decreasing effect on the drying rate of poplar wood; however, it reached to the final moisture content slower due to higher initial moisture content. َAlso, the wetwood had no significant effect on the transverse permeability but reduced the diffusion coefficient. In contrast to the wetwood effects, the drying rate, permeability and diffusion coefficients were increased due to the blue stain.

Thraustochytrid cells attach to their food via ectoplasmic nets (ENs). Here, we analyzed the cause and effect relationship between the various forms and functions of ENs of Schizochytrium aggregatum. The ENs spread out over a large area forming a fine network to efficiently search for the experimental food source. After recognizing the experimental food source, the ENs that attached to the food source became thicker, and net elements developed. The thick ENs on the surface at the attachment site were enveloped in dense materials (fibrous materials), which were visualized as fibrous layers under a transmission electron microscope. Experiments using fluorescein diacetate and the fluorescent glucose analog 2-NBDG showed that the production rate of hydrolytic enzymes and the absorption rate of glucose by ENs of S. aggregatum increased in the presence of an experimental food source. Our results reveal that ENs change their shape and function according to the presence/absence of a food source. [ABSTRACT FROM AUTHOR]

In this study, mould and blue stain susceptibility, capillary water uptake (CWU) and microstructural properties of two thermo-hydro-treated (THT) birch plywood products A and B were investigated. Plywood A represented a THT industrial plywood glued with a phenol formaldehyde (PF) adhesive. Plywood B represented panels from THT veneers glued with a PF film. The THT regimes were (temperature, °C/time, min): 150/10, 150/50, 160/10 and 160/50. Both THT plywood products and untreated samples were resistant to mould and blue stain growth in 1 month of exposure in laboratory and outdoor conditions. A statistically significant correlation between fungal growth in laboratory and outdoor conditions for plywood products A and B was not found (P > .05). Artificial weathering of both plywood products provided adverse fungal growth results compared to the natural weathering test outdoors. The fungal growth on plywood A and B samples mutually strongly correlated (P < .05) only in the outdoor test. Plywood B samples demonstrated a much lower CWU than plywood A, obviously because of microstructural changes, including densification, and type of glue used. Lower CWU of THT plywood in comparison with untreated samples did not provide clear evidence on inhibition of fungal growth. [ABSTRACT FROM AUTHOR]

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The genomes of Cercospora zeina, Fusarium pininemorale, Hawksworthiomyces lignivorus, Huntiella decipiens, and Ophiostoma ips are presented in this genome announcement. Three of these genomes are from plant pathogens and otherwise economically important fungal species. Fusarium pininemorale and H. decipiens are not known to cause significant disease but are closely related to species of economic importance. The genome sizes range from 25.99 Mb in the case of O. ips to 4.82 Mb for H. lignivorus. These genomes include the first reports of a genome from the genus Hawksworthiomyces. The availability of these genome data will allow the resolution of longstanding questions regarding the taxonomy of these species. In addition these genome sequences through comparative studies with closely related organisms will increase our understanding of how these species or close relatives cause disease. [ABSTRACT FROM AUTHOR]

Although several Botryosphaeriaceae species have been relatively well-studied on economically important crops and forest plantations, little is known regarding their presence and ecology on native tree species in the natural tropical forests in South America. Therefore, the aim of this study was to determine the fungi associated with blue stain symptoms of the wood on Ficus insipida in lumber yards from the Imataca natural forest in Eastern Venezuela using morphological descriptions and DNA sequences of the internal transcribed spacer region (ITS1-5.8S-ITS2) and part of the translation elongation factor 1-α (TEF) gene. Results of this study showed the botryosphaeriaceous taxa Lasiodiplodia theobromae and L. venezuelensis to be the main fungi associated with blue stain symptoms. This study represents the first report of these fungi on F. insipida lumber in the Natural Forest of Venezuela. [ABSTRACT FROM AUTHOR]

The potential of a lactylate (the sodium caproyl lactylate or C10 lactylate), a typical food grade emulsifier, as an anionic environmental friendly anti-fungal additive was tested in growth medium and formulated in a protective coating for exterior wood. Different laboratory growth tests on the blue stain fungus Aureobasidium pullulans were performed and its interactions on a model fungal cell membrane were studied. Promising short term anti-fungal effects in growth tests were observed, although significant but less dramatic effects took place in coating test on wood panels. Scanning electron microscope analysis shows clear differences in the amount of fungal slime on the mycelium of Aureobasidium pullulans when the fungus was exposed of C10 lactylate. This could indicate an effect on the pullulan and melanin production by the fungus. Moreover, the interaction studies on model fungal cell membranes show that C10 lactylate affects the phospholipid bilayer in a similar manner to other negative charged detergents. [ABSTRACT FROM AUTHOR]

The aim of the present paper is to investigate the influence of biotic factors (fungi and insects) on the mechanical properties of wood through the effect of blue-stain, taking into account the time of harvesting and the time of stay of wood in the forest. Specifically, the resistance to axial compression and to bending (modulus of rupture (MOR)) was studied using infected specimens of Scots Pine (Pinus sylvestris) and Norway Spruce (Picea abies) (the usual types of wood used in woodwork). The specimens were obtained from logs of Scots Pine and Norway Spruce that were harvested in three different seasons of year, namely in July 2012, November 2012 and June 2013, respectively, in the forest of Elatia-Greece, and the attack pace by biotic factors with respect to the time of logging was studied. The placement of the experimental surfaces of each type of tree was made on skid road and in the stand. Totally, 120 laboratory measurements in axial compression and 120 measurements in bending (MOR) took place. The results proved that blue-stain hardly affect the mechanical properties of both wooden species and particularly the specimens that were derived during the winter logging. [ABSTRACT FROM PUBLISHER]

Scots pine ( Pinus sylvestris L.) sapwood specimens were subjected to a two-step treatment combining vacuum-pressure impregnation with short-chain siloxanes followed by copper deposition on the wood surface via atmospheric pressure plasma. The obtained materials were exposed to a blue stain fungus in a laboratory test following EN 152 (2011). Copper treatment alone reduced fungal colonisation, but did not fully prevent it. A two-step treatment was able to impart high resistance to Aureobasidium pullulans . Termite resistance of siloxane-treated and copper-plasma coated wood was also assessed. A laboratory no-choice test according to EN 118 (2013) revealed strong attack by Reticulitermes flavipes , but termite mortality increased compared to untreated wood. In contrast, under choice conditions, R. flavipes exhibited significant avoidance towards the treated specimens. [ABSTRACT FROM AUTHOR]

Background: Malaria is the most important parasitic infection of man. Microscopy remains gold standard in malaria diagnosis. Management of malaria requires rapid detection of parasite in human blood. Hence there is a need to develop another diagnostic method with less limitation, which will address this issue. Aim and Objectives:To find a low cost reliable and accurate method for malaria detection on peripheral smear. Material and Methods: Aprospective study of 40 cases was done. Two thin smears were prepared for each case; one was stained with Leishman stain and other with new methylene blue stain and examined under oil immersion. The smears were examined individually by two pathologists and results were prepared. Different parasitic morphologic forms were looked for. Parasitemia percentage was calculated. We also compared number of fields required to diagnose with both stains in positive cases. Results: In this study we found that 25 (83.3%) cases were detected in less than 50 fields using New Methylene blue stain against 18 (60.0%) cases with Leishman stain. We also found 100% sensitivity and specificity for New Methylene blue stain, whereas Leishman stain showed 90% sensitivity and specificity of 85%. Conclusion: The detection of malaria parasite was considerably easy with New Methylene Blue stain and required less time in comparison with Leishman stain. [ABSTRACT FROM AUTHOR]

1. Invasive species with global distributions encounter unique environmental and biotic variables that can greatly affect the magnitude of their impact. The European woodwasp, Sirex noctilio Fabricius, is a prime example that has invaded climatically and ecologically distinct ecosystems across the Southern Hemisphere and, more recently, North America. 2. Northeastern North America presents a unique set of conditions, including pine host species, native parasitoids, a diverse assemblage of native co-colonising insects, and fungal associates of these co-colonisers. In North America, S. noctilio attacks both a naturalised ancestral host ( Pinus sylvestris L.) from Europe and a naïve native host ( P. resinosa). A large assemblage of insects and their associated bluestaining ophiostomatoid fungi colonise these pines. Competition between S. noctilio and this group is a hypothesised mechanism of biotic resistance in the invaded region of North America, possibly via superior resource capture abilities or alteration of host tissue by bluestain fungi. 3. Investigating these ecological interactions is challenging because they manifest deep in the xylem tissue. To overcome this, 30 experimentally stressed trees were systematically dissected with an electric log splitter to investigate the effects of bluestain fungi and tree factors on S. noctilio development and parasitism by native hymenopterans. 4. Body size and colonisation density were affected by pine species, with S. noctilio being 25% larger and densities three-fold greater in P. sylvestris than P. resinosa. Survivorship was slightly negatively correlated with the proportional volume of bluestain infection. Interestingly, rhyssine ( Rhyssa and Megarhyssa spp.) parasitism responded positively to greater S. noctilio density, but there was no density relationship with Ibalia leucospoides ensiger parasitism. Pine host species appears to play a strong role in S. noctilio development, which is important considering uninvaded regions of North America have a diversity of pine species that likely vary in their susceptibility to this woodborer. [ABSTRACT FROM AUTHOR]

Bark beetles (Coleoptera, Scolytinae) have a widespread association with fungi, especially with ophiostomatoid fungi (Ascomycota) that cause blue staining of wood, and in some cases, serious tree diseases. In Fennoscandia, most studies of these fungi have focused on economically important bark beetle species and this is likely to have led to a biased view of the fungal biodiversity in the region. Recently, the associations between fungi and bark beetles in Fennoscandia have been shown to be more diverse than previously thought. Furthermore, they form complex and dynamic associations that are only now beginning to emerge. This review examines the current knowledge of the rather poorly known interactions between bark beetles, fungi and their conifer host trees in Fennoscandia. The diversity of ophiostomatoid species is discussed and the possible factors that influence the assemblages of fungal associates are considered for all species that are known to occur in the region. For many ophiostomatoid species found in Fennoscandia, little or nothing is known regarding their pathogenicity, particularly if they were to be transferred to new environments. We, therefore, draw attention to the possible threats of timber trade and climate change-induced invasions of new habitats by bark beetles and the fungi that can be moved along with them.

La madera de Pinus sylvestris tiene interés comercial aunque su valor se reduce considerablemente cuando presenta hongos de azulado. En el presente estudio se apearon siete pinos procedentes de plantaciones españolas, y de los fustes se muestrearon 14 rodajas a diferentes alturas. Cuando éstas estaban parcialmente azuladas se labraron para obtener probetas pequeñas sin defectos anatómicos, sobre las que se determinó la densidad y además la estabilidad dimensional en volumen y en las tres dimensiones principales de la madera. En cada rodaja se compararon las propiedades físicas de las probetas completamente azuladas y las no azuladas, mediante el análisis de la varianza con un factor. El método permitió analizar la influencia específica del azulado eliminando otras fuentes de variación: factor árbol, altura en el fuste, anchura de anillos, presencia de albura y edad cambial. Solo en algunas rodajas la madera azulada de pino silvestre resultó significativamente diferente en densidad y contracción axial (madera azulada un 1% más densa y con la contracción axial un 13% mayor).Pinus sylvestris timber is commercially important, but its value is considerably decreased by the effects of blue stain fungi. Seven pine trees from Spanish plantations were felled for the study, and 14 discs were sampled from different heights in their stems. When the discs showed partial discolouration due to fungal infection, they were cut to produce small defect-free specimens for determining density and dimensional stability (in volume and in the three main dimensions of wood). The physical properties of fully stained and stain free specimens were compared, in each disc, by one-factor analysis of variance. This method enabled analysis of the specific influence of the blue stain fungi while avoiding other sources of variation: tree factor, height in the stem, ring width, presence of sapwood and cambial age. However, the only significant differences between discoloured and unstained wood were in the density and axial shrinkage, in some discs (the density of the blue-stained wood was 1% higher and the axial shrinkage 13% higher than in the unstained wood).

Thermally modified timber (TMT) is increasingly offered in Europe as an alternative to preservative treated timber. TMT durability in field tests as well as its moisture sorption behaviour in façade application was determined so as to consider its suitability for outdoor use. Additionally, abrasion and crack-formation of TMT deckings were examined and the optical appearance of a TMT façade was evaluated after 5 years of service. After 7.5 years exposure in ground contact, the various TMT materials tested were classed as “slightly durable” to “not durable” whereas the classification in above ground exposure as “very durable” to “moderately durable”, which was in line with the reduced moisture sorption of TMT in weathered application. Moreover, the TMT-decking showed less abrasion and crack-formation compared to references, though the TMT façade revealed considerable discoloration by weathering. Hence, the suitability of TMT for above ground use is suggested, but a surface treatment is obligatory if discoloration is objectionable.

According to FAO - ISPM No 15, in international trade wood packaging material on the basis of sawn timber requires to be heat-treated to avoid spreading of harmful organisms. "Heat-treatment" means a minimum core temperature of the wood of 56° C for a minimum of 30 minutes. ISPM No 15 does not define moisture content and therefore does not include rules for the drying process. Practitioners report that fresh sapwood, after having undergone a pure heat treatment without any kind of drying, shows a great affinity to fungi (mould and blue stain). Even though the infestation does not affect the strength properties of the wood, it must be considered as an optical and a sanitary problem. An environmentally friendly, cheap and easy to use technique for temporary anti-mould protection of heat-treated wood is needed to bridge the time span between sawing, heat treatment and air or kiln drying. Results derived from laboratory experiments have shown that the heat-treatment affects the elution of the lipid components within pine sapwood. While searching for alternatives to conventional preservation methods, different environmentally compliant agents (particularly aqueous solutions containing sodium- and potassium carbonate) were found to inhibit the germination of mould and blue stain fungi spores on wood packaging material surfaces in a temporary manner. Besides their effectiveness, the usage of these agents to achieving the temporary protection (e.g. for a couple of weeks) is economically feasible and easily applicable in industrial practice. However, drying (either naturally or technically) is indispensable to avoid fungal hazard on the long run. A combination of temporary treatment immediately after sawing followed by a drying-process (long lasting protection) seems to be the most effective method to protect ISPM No 15 treated wood packaging material against mould

Bacillus subtilis is a potent biocontrol agent producing a wide array of antifungal lipopeptides for the inhibition of fungal growth. B. subtilis B1 isolated from market-available compost provided an efficient control of rubberwood sapstain fungus, Lasiodiplodia theobromae. The current study is aimed to identify and characterize the lipopeptides responsible for the biocontrol of rubberwood sapstain fungus by Bacillus subtilis B1. The bacterial whole-cell surface extract from the dual culture of B. subtilis B1 and sapstain fungus ( L. theobromae) was analysed using MALDI-TOF-MS. The protonated as well as sodium, potassium adducts of homologues of iturin C, surfactin, bacillomycin D and fengycin A and B were identified and expression of the lipopeptide biosynthetic genes could be confirmed through RT-PCR. This is the first report of mycobacillin and trimethylsilyl derivative of bacilysin during antagonism through MALDI-TOF-MS. MALDI-TOF-MS with RT-PCR offered easy platforms to characterize the antifungal lipopeptides. The identification of antifungal lipopeptides can lead to the formulation of prospective biocontrol by-products which have wide-scale utility. [ABSTRACT FROM AUTHOR]

The ophiostomatoid fungi (Microascales and Ophiostomatales, Ascomycota) are common associates of Ips typographus, and include tree pathogens and species responsible for blue-stain of timber. Fungal assemblages associated with I. typographus have varied considerably between studies but few investigations have attempted to explain this variation. For this reason, we assessed the overall cultivable fungal diversity associated with I. typographus in a storm-felled spruce forest in south-eastern Finland. Fungi were isolated from the individually collected beetles as well as their phoretic mites in spring, summer and autumn, including different life stages of the beetle (hibernation, dispersal flight and first generation). The internal transcribed spacer (ITS) gene region was used to identify the fungi. A total of 32 operational taxonomic units (OTUs) were found and these resided in four fungal phyla/subphyla (24 Ascomycota, 2 Basidiomycota, 5 Mucoromycotina, 1 Mortierellomycotina) in association with adult bark beetles. Ophiostomatoid species were the most commonly detected fungal associates. A generalized linear model analysis showed a clear association between fungal communities and season, indicating seasonal succession among I. typographus-associated fungi. The season of sampling appears to be an important factor that has resulted in inconsistencies between results in previous studies. Many of these fungi were also found on phoretic mites and their presence or absence could have influenced variation in patterns of association. [ABSTRACT FROM AUTHOR]

This study investigated the effects of felling season on the discoloration of rubberwood sawn timber during conventional kiln drying. The samples were collected throughout the year 2015 to monitor the variation of free sugars and starch content in the rubberwood logs. Two batches of logs, one from the rainy season and the other from the dry season, were felled and sawn for experimentation. The findings showed that discoloration was more prominent in sawn timber obtained from logs felled during the dry season. The amount of free sugars and starch in the logs had a strong influence on the extent of discoloration in the rubberwood sawn timber during the kiln drying process. A higher amount of free sugars and starch in the logs felled during the dry season increased the incidence of blue stain on these logs. The results of this study conclusively showed that discoloration in rubberwood can be minimized by the choice of log felling season and the use of an appropriate drying technique, which will inevitably improve the aesthetic appeal of the wood. [ABSTRACT FROM AUTHOR]

The aesthetic value of the rubberwood is lost due to the bluish black discolouration caused by sapstain fungus, Lasiodiplodia theobromae , which leads to an economic loss in the wood industry. In our earlier study, Bacillus subtilis B1 has been identified as the potential biocontrol agent against L. theobromae , the dominant sapstain fungus infecting the rubberwood. Bacillus subtilis is known for its biocontrol activity against a wide range of fungal pathogens by various means including the action of non-ribosomal antifungal lipopeptides viz . iturin, surfactin and fengycin. The present study aims to characterize and quantify the gene expression levels of these antifungal lipopeptidic genes using RT-qPCR during inhibition process in the dual culture. Among the three lipopeptide genes, fengycin biosynthetic gene was constantly expressed in high amounts throughout the antagonism. The gene for surfactin biosynthesis was also expressed all through and may have helped in the growth and spreading of B. subtilis ​B1. Bacilysin biosynthetic gene expressed only in the fourth and fifth days dual culture might have complemented the action of fengycin in inhibiting the sapstain fungus. [ABSTRACT FROM AUTHOR]

Thin layers of copper micro-particles were deposited on the surfaces of Scots pine ( Pinus sylvestris L.) micro-veneers using atmospheric pressure plasma to improve the resistance of the surfaces to weathering. Three different loadings of copper were established. Micro-veneers were exposed to artificial weathering in a QUV weathering tester for 0, 24, 48, 96 and 144 h following the standard EN 927-6 [1] . Mass losses after each exposure showed significant differences between copper coated and untreated micro-veneers. Tensile strength was assessed at zero span (z-strength) and finite span (f-strength) under dry conditions (20 °C, 65% RH). During 48 h, micro-veneers lost their z-strength progressively. In contrast, copper coating at highest loading imparts a photo-protective effect to wood micro-veneers during 144 h exhibiting z-strength retention of 95%. F-strength losses were similar in all copper treated and untreated micro-veneers up to 96 h. However, after 144 h, copper coated micro-veneers at highest loading showed significantly greater strength retention of 56%, while untreated micro-veneers exhibited only 38%. Infrared spectroscopy suggested that copper coating does not stabilize lignin. Inductively Coupled Plasma revealed that micro-veneers coated with the highest loading exhibited the lowest percentage of copper loss. Blue stain resistance of copper coated Scots pine following the guidelines of EN 152 [2] was performed. Additional test with different position of the coated surface was also assessed. Copper coating reduced fungal growth when coated surface is exposed in contact with vermiculite. Spores of Aureobasidium pullulans were not able to germinate on the copper coated surface positioned uppermost. [ABSTRACT FROM AUTHOR]

According to FAO – ISPM No 15, in international trade wood packaging material on the basis of sawn timber requires to be heat-treated to avoid spreading of harmful organisms. “Heat-treatment” means a minimum core temperature of the wood of 56° C for a minimum of 30 minutes. ISPM No 15 does not define moisture content and therefore does not include rules for the drying process. Practitioners report that fresh sapwood, after having undergone a pure heat treatment without any kind of drying, shows a great affinity to fungi (mould and blue stain). Even though the infestation does not affect the strength properties of the wood, it must be considered as an optical and a sanitary problem. An environmentally friendly, cheap and easy to use technique for temporary anti-mould protection of heattreated wood is needed to bridge the time span between sawing, heat treatment and air or kiln drying. Results derived from laboratory experiments have shown that the heat-treatment affects the elution of the lipid components within pine sapwood. While searching for alternatives to conventional preservation methods, different environmentally compliant agents (particularly aqueous solutions containing sodiumand potassium carbonate) were found to inhibit the germination of mould and blue stain fungi spores on wood packaging material surfaces in a temporary manner. Besides their effectiveness, the usage of these agents to achieving the temporary protection (e.g. for a couple of weeks) is economically feasible and easily applicable in industrial practice. However, drying (either naturally or technically) is indispensable to avoid fungal hazard on the long run. A combination of temporary treatment immediately after sawing followed by a drying-process (long lasting protection) seems to be the most effective method to protect ISPM No 15 treated wood packaging material against mould.

The development of appropriate chemical precursors that can covalently functionalize natural wood aims at efficient restriction of deterioration. Biological staining experiments were performed with veneer pieces made of sapwood of Scots pine ( Pinus sylvestris L.) that had previously been chemically modified with substituted benzoates. Based on the recently published protocol on esterification of wood by means of 1 H-benzotriazole activation, the quantity of covalently bonded organomaterials (QCOs), a recently defined advantageous value considering the individual molecular weight of the functionalizing organochemical groups, was obtained in the range of 0.9-1.5 mmol g-1. The modified wood was analyzed by attenuated total reflection IR spectroscopy. Modification with three electronically different benzoates clearly reduced the colonization of the specimen's surfaces by the blue stain fungus Aureobasidium pullulans but did not fully prevent it. The degree of colonization appeared to decrease with increasing QCO values of the modification agents but apparently did not strongly depend on the additional functionality of the benzoate. [ABSTRACT FROM AUTHOR]

The genomes of Chrysoporthe austroafricana, Diplodia scrobiculata, Fusarium nygami, Leptographium lundbergii, Limonomyces culmigenus, Stagonosporopsis tanaceti, and Thielaviopsis punctulata are presented in this genome announcement. These seven genomes are from endophytes, plant pathogens and economically important fungal species. The genome sizes range from 26.6 Mb in the case of Leptographium lundbergii to 44 Mb for Chrysoporthe austroafricana. The availability of these genome data will provide opportunities to resolve longstanding questions regarding the taxonomy of species in these genera, and may contribute to our understanding of the lifestyles through comparative studies with closely related organisms. [ABSTRACT FROM AUTHOR]

The presence of blue-stain fungi considerably decreases the value of Pinus radiata timber, which is commercially important in Galicia (NW Spain). For this study, seven young pine trees growing in four different plantations were felled, and 20 discs were sampled from different heights in the stems. Parts of the discs were discoloured as a result of fungal infection. The discs were cut into small specimens. Defect-free specimens (controls) were selected for determining density and dimensional stability both in the volume and in the axial direction. Physical properties of fully blue-stained specimens and the controls were compared for each disc based on one-factor analysis of variance. As the factor was blue-stain, the other sources of variation were suppressed, such as tree source, height in the stem, ring width, cambial age and presence of heartwood or sapwood. Most of the physical properties analysed on some sample discs differed significantly between discoloured and unstained wood. The variables most affected by blue stain were basic density and volumetric shrinkage: blue-stained wood was 1.1% lighter and volumetric shrinkage was 5% higher in blue-stained wood than in the controls. [ABSTRACT FROM AUTHOR]

The capability of Trichoderma gamsii to biologically control sapstain fungi has been investigated. Six ophiostomatoids, including Ophiostoma floccosum, O. piceae, O. piliferum, O. ips, Grosmannia koreana, and G. piceaperda, were inhibited by the extracts of T. gamsii. Of the various cultivation periods, 7 days of T. gamsii cultivation produced antifungal compounds most efficiently. The crude extracts of T. gamsii inhibited O. ips, G. koreana, and G. piceaperda by over 99%. The crude extracts of T. gamsii were isolated, and the compounds were purified by thin layer chromatography (TLC), open column chromatography, ultra-performance liquid chromatography combined with quadrupole time-of-flight mass spectrometry (UPLC-QToF-MS) and NMR spectroscopy. The active fractions were separated based on the degree of T. gamsii antifungal activity. The compound 6-pentyl-α-pyrone (6PAP) was evaluated as a biological control agent for sapstain fungi. [ABSTRACT FROM AUTHOR]