Effect of stand thinning, former land use and individual tree parameters on wood inhabiting fungal community composition in young living Norway spruce

We investigated the wood fungal community composition in stems of living Norway spruce (Picea abies (L.) Karst.) trees in 20–40 year-old forest stands from Latvia that differed in recent management history (stands with or without thinning) and former land use (former agricultural or former forest lands). Fungal internal transcribed spacer (ITS2) amplicons of DNA extracted from wood were sequenced to assess wood fungal communities. Alternaria, Ascocoryne, Didymella, Heterobasidion, Ophiostoma, Orbilia, Pesotum, Phoma and Pseudocercosporella were the dominant wood pathogen and wood saprotroph genera in the analysed samples. PERMANOVA analysis identified some differences in fungal communities among site types analysed (p < 0.001); tree height and presence/absence of rot in the wood samples (mainly Heterobasidion rot) significantly influenced fungal community composition (p < 0.001). Significant negative co-occurrence (p < 0.05) was observed between Heterobasidion and Ascocoryne genera indicating the differing wood colonizing niches of these taxa. Both stand level factors, such as management history and former land use, and tree level parameters are significant for wood inhabiting fungal communities of living spruces.