Study on Improving in the Evaluation of Untreated Specimens in the Decay Resistance Effect of Wood Preservatives

Abstract

This study emphasizes the importance of verifying the vitality of test fungi through the results of untreated specimens in the evaluation of the efficacy of wood preservatives. However, in many cases, the weight loss of the untreated specimens does not meet the criteria in the Korean standard(KS) test method, so we devised an efficient and simplified test method by cross-applying the American Wood Protection Association (AWPA) standard method. The study found that the feeder strip inoculation method specified in the soil block test(AWPA) was more effective than the KS standard, resulting in a higher weight loss (%) of the wood blocks. Among the strains used, <i>Trametes versicolor</i> KACC54448(white rot fungus) showed weight loss rate of 34.1% and <i>Tyromyces palustris</i> and <i>Fomitopsis pinicola</i> KACC53387(brown rot fungi) showed weight loss rates of 63.9%, 58.0%, respectively. Furthermore, we found that maintaining a relative humidity of around 50% by placing distilled water in a low-temperature incubator was sufficient to create an environment in which the test fungi could decay the wood blocks without using expensive equipment such as a constant temperature and humidity chamber. As a result, it was confirmed that the activity of the test fungi can be increased even under conditions of around 50% relative humidity without the shaking cultivation process of the test fungi.