Fungicide efficacy of nanofibre textiles containing chemical preservatives for protection of wooden materials – preliminary study

The aim of presented work was to verify a possible application of nanofibre polyvinyl alcohol (PVA) textiles doped with commercially available biocides for chemical preservation of wooden materials. Fungicide efficacy of biocides based on Propiconazole, Tebuconazole, IPBC was evaluated on Norway spruce samples (Picea abies Karst. L.) 25 x 25 x 4 mm covered by the nanofibre textiles, against the wood destroying fungus Coniophora puteana during 28 days. Decay resistance of spruce samples with the fungicidally treated layer was valued on the base of weight loss (Δm) criteria. The durability of spruce samples significantly increased after incorporation of fungicides into the nanofibre textiles (Δm from 0.2 to 3.7 %), but the influence of the stabilization process was also reflected.

Indoor fungal destroyers of wooden materials – their identification in present review

The wood-destroying fungi traditionally were separated from one another primarily on a basis of their sporocarp and/or strain morphology. Their diversity and simple macro- and micromorphology of fungal structures have been major obstacles for more rapid progress in this regard. However, over the past two decades, there has been substantial progress in our understanding of genetic variability within traditionally recognized morphospecies. In this study we have overviewed genetic variation and phylogeography of macrofungi, which are important destroyers of wooden materials indoor of buildings. Several morphologically defined species of these fungal destroyers (Coniophora puteana, C. olivacea, C. arida, Serpula himantioides) have been shown to actually encompass several genetically isolated lineages (cryptic species). The protective efficacy against cryptic species within traditionally recognized morphospecies through laboratory tests (EN 113) and field trials (EN 252) might be sufficient to better prognosis of decay development in wooden materials for hazard assessment and for proper conservation and management plans.

Short note: The impact of glue-lines on the protective effect of a low- pulsed electric field in wood

A wood protection method using electric fields to inhibit wood decay by brown rot fungi has been investigated in laboratory trials. Glued and non-glued wood samples were exposed to fungal attack for 6 weeks in Petri dishes and showed significantly reduced mass loss when connected to a low pulsed electric field (LPEF). The mass loss of LPEF-protected samples was in average lower than 10%, with a wood moisture content above 40%. The mass loss of untreated wood samples was above 30% in average. The glue line did not represent a barrier for the electric field in the test setup (a), where the glue line was applied on the transverse section of two glue-jointed wood sample halves. A test setup with two glue lines at the tangential side of three jointed wood samples, showed only slightly higher mass loss compared with wood samples consisting of two jointed halves. It is concluded that glue lines using the MUF glue mix used in this study do not impede the protective effect of LPEF.