Forest Products Laboratory

Use of Ectomycorrhizal (ECM) Fungi for of Treated Wood Wastes Wood is an excellent building material and is suitable for a wide range of residential and industrial applications. Wood is a biodegradable biopolymer and is often pressure treated to extend its useful service life. Preservative-treated wood is required for critical members and structural elements in contact with soil by the uniform building code, both nationally and internationally. However, the presence of preservatives complicates end-of-life disposal and downstream reuse of these materials because of residual metals and co-biocides. Past research has utilized wood decay fungi with inherent tolerance or resistance to metals in attempts to detoxify wood wastes (Harms et al. 2011). Ectomycorrhizal (ECM) fungi—an often overlooked but vital part of the forest —have been Mycelia of Amanita spp. colonizing plant root tips. (Source: shown to tolerate high levels of metal contamination. Nilsson, R.H.; Kristiansson, E.; Ryberg, M.; Larsson, K.-H. 2005. Approaching the taxonomic affiliation of unidentified sequences in public databases—an example from the mycorrhizal fungi. Background BMC Bioinformatics 6: 178. DOI:10.1186/1471-2105-6-178. This Treated wood waste constitutes a significant input to file is licensed under the Creative Commons Attribution 2.5 landfills despite almost three decades of research on Generic license.) effective and reuse. Traditional studies of ECM fungi as a bioremediation tool could to a have relied on - or chemical-mediated leaching reduce volume of treated wood waste that is otherwise of metalloid components, which removes them from deposited in landfills. the woody biomass but offers no means of effective removal from the surrounding environmental matrix Objective (Baldrian 2008). Ectomycorrhizal fungi have been demonstrated to tolerate contamination and often thrive The goal of this work is to develop laboratory-scale in metal-contaminated sites (Meharg and Cairney tests to assess the ability of ECM fungi to immobilize 2000; Kirker et al. 2017). These fungi have also been in a model system contaminated with shown to serve as a critical intermediate in metal heavy metals representative of chemical contaminants uptake and subsequent uptake by colonized plants. found in treated wood waste. The ultimate goal would The capacity of ECM fungi to transport and bind be to refine this process to provide a closed loop for metals in their biomass could theoretically be used in reclaiming metal contaminants from the environment bioremediation of treated wood waste; however, this is rather than simply releasing them back into the soil as an unexplored area of research. Further development they are leached.

U.S. Department of Agriculture • Forest Service Forest Products Laboratory www.fpl.fs.fed.us RIP-4723-043

Timeline Project will begin summer of 2020 and continue until 2024.

Cooperators USDA Forest Service, Forest Products Laboratory Oregon State University, Department of Wood Science and Engineering

Contact Information Grant Kirker USDA Forest Service, Forest Products Laboratory Madison, Wisconsin [email protected] Katie M. Ohno USDA Forest Service, Forest Products Laboratory Madison, Wisconsin [email protected] Boletus spp. serving as a photographic example of a common ectomycorrhizal fungus. (Photo credit: Jed Cappellazzi, Oregon Gerald Presley State, Department of Wood Science and Engineering.) Department of Wood Science and Engineering (©2020, Jed Cappellazzi. Used by permission.) Oregon State University Corvallis, Oregon Approach [email protected] Laboratory and field bioassays will be developed to assess the ability of select ECM fungi to detoxify References treated wood waste. Laboratory trials will be used Baldrian, P. 2008. Wood-inhabiting ligninolytic to screen ECM fungi of interest for their capacity to basidiomycetes in soils: ecology and constraints for bioaccumulate and immobilize . Scale-up and applicability in bioremediation. Fungal Ecology. 1(1): field trials will be performed if time permits within 4–12. the funding period. Oregon State University has a long-term field site specifically dedicated to wood Harms, H.; Schlosser, D.; Wick, L.Y. 2011. Untapped preservative research. This site is ideal for studying potential: exploiting fungi in bioremediation of the remediation of soils that have had long-term hazardous chemicals. Nature Reviews Microbiology. contact with treated wood and can be used to validate 9(3): 177–192. laboratory-based screening tests. Kirker, G.T.; Bishell, A.B.; Jusino, M.A.; Palmer, J.M.; Hickey, W.J.; Lindner, D.L. 2017. Amplicon-based Expected Outcomes sequencing of soil fungi from wood preservative test The outcomes of this work would build on sites. Frontiers in Microbiology. 8: 1997. foundational studies and potentially provide more Meharg, A.A.; Cairney, J.W. 2000. Ectomycorrhizas— effective processes for removing contaminants from extending the capabilities of rhizosphere remediation? treated wood waste and the surrounding environment. Soil Biology and Biochemistry. 32(11): 1475–1484. Improvement and implementation of this process would reduce inputs on landfills and potentially open up downstream processing potential for treated wood waste.