TY - JOUR

T1 - Copper in wood preservatives delayed wood decomposition and shifted soil fungal but not bacterial community composition

AU - Lasota, Sandra

AU - Stephan, Ina

AU - Horn, Marcus Andreas

AU - Otto, Wolfgang

AU - Noll, Matthias

N1 - Funding Information: Funding was provided by the Deutsche Bundesstiftung Umwelt (award AZ 29621-31). Kurt Obermeier GmbH & Co. KG supported this study by providing impregnated wooden stakes and access to research sites. Bundesanstalt für Materialforschung und -prüfung enabled the incubation and analyzed abiotic parameters of the soil sampling sites, mass loss, and MOE. We thank Laura Schwab, Sarah Sheena Fink, Katharina Trunzer, Sabrina Trawny, Christian Reger, and Kerstin Klutzny for technical assistance and Judith Schuster and Peter Askew for proofreading the manuscript.

PY - 2019/2/6

Y1 - 2019/2/6

N2 - Copper-based fungicides are routinely used for wood and plant protection, which can lead to an enrichment of copper-tolerant microbial communities in soil. To investigate the effect of such wood preservatives on the soil fungal and bacterial community compositions, five different vineyard and fruit-growing soil environments were evaluated using incubation studies over time. Pine sapwood specimens were impregnated with either water or different biocide treatment solutions containing a mixture of copper, triazoles, and quaternary ammonium compounds (CuTriQAC), a mixture of triazoles and quaternary ammonium compounds (TriQAC), or copper alone (Cu). Specimens were incubated in soil from each sample site for 8, 16, 24, and 32 weeks. The effects of preservative treatment on the modulus of elasticity (MOE) of the wood specimens and on the soil fungal as well as bacterial community composition at the soil-wood interface were assessed by quantitative PCR and amplicon sequencing of the fungal internal transcribed spacer (ITS) region and bacterial 16S rRNA gene. Specimens impregnated with CuTriQAC and Cu showed decreased MOE and reduced fungal and bacterial copy numbers over time compared to those impregnated with water and TriQAC. Fungal but not bacterial community composition was significantly affected by wood preservative treatment. The relative abundance of members of the family Trichocomaceae compared to other genera increased in the presence of the Cu and CuTriQAC treatments at three sites, suggesting these to be Cu-tolerant fungi. In conclusion, the copper-containing treatments resulted in marginally increased MOE, lowered microbial gene copy numbers compared to those in the TriQAC and water treatments, and thus enhanced wood protection against soil microbial wood degradation.

AB - Copper-based fungicides are routinely used for wood and plant protection, which can lead to an enrichment of copper-tolerant microbial communities in soil. To investigate the effect of such wood preservatives on the soil fungal and bacterial community compositions, five different vineyard and fruit-growing soil environments were evaluated using incubation studies over time. Pine sapwood specimens were impregnated with either water or different biocide treatment solutions containing a mixture of copper, triazoles, and quaternary ammonium compounds (CuTriQAC), a mixture of triazoles and quaternary ammonium compounds (TriQAC), or copper alone (Cu). Specimens were incubated in soil from each sample site for 8, 16, 24, and 32 weeks. The effects of preservative treatment on the modulus of elasticity (MOE) of the wood specimens and on the soil fungal as well as bacterial community composition at the soil-wood interface were assessed by quantitative PCR and amplicon sequencing of the fungal internal transcribed spacer (ITS) region and bacterial 16S rRNA gene. Specimens impregnated with CuTriQAC and Cu showed decreased MOE and reduced fungal and bacterial copy numbers over time compared to those impregnated with water and TriQAC. Fungal but not bacterial community composition was significantly affected by wood preservative treatment. The relative abundance of members of the family Trichocomaceae compared to other genera increased in the presence of the Cu and CuTriQAC treatments at three sites, suggesting these to be Cu-tolerant fungi. In conclusion, the copper-containing treatments resulted in marginally increased MOE, lowered microbial gene copy numbers compared to those in the TriQAC and water treatments, and thus enhanced wood protection against soil microbial wood degradation.

KW - 16S rRNA gene

KW - Amplicon sequencing

KW - Community composition

KW - Copper-based wood preservatives

KW - ITS region

KW - Soil incubation study

UR - http://www.scopus.com/inward/record.url?scp=85061149941&partnerID=8YFLogxK

U2 - 10.1128/AEM.02391-18

DO - 10.1128/AEM.02391-18

M3 - Article

VL - 85

JO - Applied and Environmental Microbiology

JF - Applied and Environmental Microbiology

SN - 0099-2240

IS - 4

M1 - e02391-18

ER -