Dataset to 'Fungistatic effects of purified conifer tannins against five wood-decaying fungi' by Thitz et al. (Fungal Ecology)

Dataset related to the manuscript 'Fungistatic effects of purified conifer tannins against five wood-decaying fungi', authored by Thitz, Karonen, Barbero-López, Haapala and Virjamo. Reviewed manuscript was accepted for publication in Fungal Ecology on 21.1.2026. Dataset includes research data presented in the manuscript, scripts required for reproducing analysis, tables and figures and photos of petri dishes taken at the end of the fungal growth experiments.For questions, contact paula.thitz(at)helsinki.fi.We tested the antifungal activity of condensed tannins and alkaloids purified from needles and bark of two conifers (Picea abies and Pinus sylvestris) against wood-decomposing fungi in vitro, by measuring fungal growth when the purified plant metabolites (condensed tannins or alkaloids) were added to malt agar compared to the control treatment. Comparison of tannin responses in brown rot fungi specialized on conifers did not reveal different resilience compared to unspecialized white rot fungi, but we found the average degree of polymerization of condensed tannins to negatively associate with fungistatic effects. Despite variable fungal responses, condensed tannins seemed to have generalized antifungal activity based on the studied saprotroph species. Tests of tannin-alkaloid interaction against the selected brown-rot fungi did not reveal synergistic or antagonistic effects of Norway spruce metabolites, at least when metabolites were added to agar growth medium shortly before the beginning of the experiment.