Year:
2003
Publication type:
Miscellaneous Publication
Primary Station(s):
Forest Products Laboratory
Source:
International biodeterioration & biodegradation. Vol. 51 (2003): Pages 145-149
Description
The increase in the use of non-arsenical copper-based wood preservatives in response to environmental concerns has been accompanied by interest in copper-tolerant decay fungi. Oxalic acid production by brown-rot fungi has been proposed as one mechanism of copper tolerance. Fifteen brown-rot fungi representing the genera Postia, Wolfiporia, Meruliporia, Gloeophyllum, Laetiporus, Coniophora, Antrodia, Serpula, and Tyromyces were evaluated for oxalic acid production bi-weekly in southern yellow pine (SYP) blocks treated with 1.2% ammoniacal copper citrate (CC). Eleven fungi were designated copper-tolerant based upon weight loss in CC-treated blocks. After 2 weeks, these fungi produced 2-17 times more oxalic acid in CC-treated blocks than in untreated blocks. After 10 weeks, weight loss ranged from 32% to 57% in CC-treated SYP. Four fungi were copper sensitive, producing low levels of oxalic acid and minimal weight loss in CC-treated blocks. Rapid induction of oxalic acid appeared to correlate closely with copper tolerance. We conclude that the brown-rot fungi tested that were able to exceed and maintain an oxalic acid concentration of > 600 µmol/g effectively decayed SYP treated with CC.
Citation
Green, Frederick; Clausen, Carol A. 2003. Copper tolerance of brown-rot fungi : time course of oxalic acid production. International biodeterioration & biodegradation. Vol. 51 (2003): Pages 145-149