Wood decay fungi damage wood by production of enzymes that attack the structural components. The objective of this study was to better understand which suite of decay genes and proteins are expressed during biodeterioration of three different wood types in forest soil over time. Variation in decay genes and proteins were determined for pine (non-resistant), cedar (naturally durable), and ACQ-treated pine (chemically resistant) in a soil decay bed. Decay was assessed by visual decay ratings, dynamic MOE, and microscopy. There were no significant difference in decay between cedar and ACQ-treated pine over the 18 month period. However, there were significant differences in decay between pine and cedar and between pine and ACQ-treated pine. The fungal mycelia penetrated the cell walls of pine and were continually observed over 18 months, but not in cedar or ACQ-treated pine. Basidiomycetes containing decay genes were detected on pine which also had a greater diversity of fungi compared to cedar and ACQ-treated pine. No basidiomycete genes were expressed and only a few basidiomycetes were identified on cedar which also showed little decay. ACQ-treated pine also showed a little decay however basidiomycetes were present and active. Proteins were first detected on pine and ACQ-treated pine at 6 months and the numbers continued to increase through 18 months, but were not detected on cedar until 14 months. There was greater number of total proteins on pine than cedar and ACQ-treated pine at each time period. From these results, the natural durability of cedar reduced the wood decay community and its activities. It appears that ACQ-treated wood did not stop the growth of the decay fungi and the production of the decay enzymes but the chemical treatment did inhibit the effectiveness of the enzymes thus decay.

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