Cost Action E37 Final Conference in Bordeaux 2008 Socio-economic perspectives of treated wood for the common European market Limiting fungal spread in buildings without the use of toxic biocides

By preventing amino acid translocation through mycelial networks, the spread of wood decay fungi within building structures can be contained, and sound joinery protected from attack. The amino acid analogue AIB (α-aminoisobutyric acid) competitively excludes utilisable amino acids from the mycelium, and from the nutrient supply network of mycelial cords that enables basidiomycete fungi including S. lacrymans to spread through buildings. AIB inhibits all basidiomycetes tested including Serpula lacrymans, Coniophora puteana, Gloeophyllum trabeum, Lentinus lepideus and Coriolus versicolor. It is effectively non-toxic to non-target organisms and biodegrades in soil. Here we report the application of a radiolabelled 14C-AIB marker to establish the power of locally applied AIB to arrest extension throughout a whole mycelial network, irrespective of the point of application. Real time imaging by PCSI was used to track the velocity and direction of AIB translocation in microcosms designed to mimic building timber elements in a masonry structure. AIB applied at any point in the mycelial network rapidly permeated the whole fungal system, resulting in durable inhibition of extension. Mycelial extension ceased and the development of the foraging network was delayed and disorganised. Experiments on the partitioning of AIB between partially exhausted and fresh wood food sources showed that AIB was preferentially translocated to sites of attack on fresh wood, where it accumulated. AIB is licensed for experimental use on a site by site basis, and is suitable for controlling spread of dry rot, particularly to conserve wood and cellulosic materials in historic buildings infected with Serpula lacrymans