The Inhibitory Effect of Silver Nanoparticles on Fomitopsis pinicola Growth and Their Application in Scots Pine Wood Protection

Sustainable development in wood technology demands eco-friendly alternatives to conventional preservatives, positioning nanotechnology as a promising frontier for green wood protection. The antifungal potential of silver nanoparticles (AgNPs) against the brown-rot agent Fomitopsis pinicola was investigated in vitro, alongside an assessment of their protective performance on Scots pine wood. AgNPs were tested at 5, 25, 50, and 100 ppm in vitro, with an additional 200 ppm concentration included in the wood-decay test. In the in vitro assays, lower concentrations (5 and 25 ppm) stimulated radial mycelial growth, 50 ppm showed no effect, and 100 ppm caused growth inhibition. In contrast, all tested concentrations enhanced the decay resistance of pine wood. Average wood mass loss ranged from 4.9% to 8.1% after 2 months and from 10.9% to 18.6% after 4 months, with the maximum protective effect observed at 50 ppm. While AgNPs did not entirely prevent F. pinicola-induced decay, they significantly mitigated mass loss. These findings highlight the potential of AgNPs for the short-term preservation of freshly harvested timber, particularly storm- or disaster-damaged wood stored in forests or log yards prior to processing.