Molecular fungal community and its decomposition activity in sapwood and heartwood of 13 temperate European tree species

Abstract

Deadwood is an important structural component in forest ecosystems and plays a significant role in global carbon and nutrient cycling. Relatively little is known about the formation and decomposition of CWD by microbial communities in situ and about the factors controlling the associated processes. In this study, we intensively analyzed the molecular fungal community composition and species richness in relation to extracellular enzyme activity and differences in decomposing sapwood and heartwood of 13 temperate tree species (four coniferous and nine deciduous species, log diameter 30–40 cm and 4 m long) in an artificial experiment involving placing the logs on the forest soil for six years. We observed strong differences in the molecular fungal community composition and richness among the 13 tree species, and specifically between deciduous and coniferous wood, but unexpectedly no difference was found between sapwood and heartwood. Fungal species richness correlated positively with wood extractives and negatively with fungal biomass. A distinct fungal community secreting lignocellulolytic key enzymes seemed to dominate the decomposition of the logs in this specific phase. In particular, the relative sequence abundance of basidiomycetous species of the Meruliaceae (e.g. Bjerkandera adusta ) correlated with ligninolytic manganese peroxidase activity. Moreover, this study reveals abundant white-rot causing Basidiomycota and soft-rot causing Ascomycota during this phase of wood decomposition.

Tree Root Zone Microbiome: Exploring the Magnitude of Environmental Conditions and Host Tree Impact

“…PCR genomic DNA amplicon libraries of the targeted microorganisms (bacteria and fungi) were produced from the genomic DNA templates. The bacterial 16S and fungal ITS2 within the rDNA region were amplified using a modified primer mix: P5_8N_515F + P5_7N_515F (forward) together with P7_2N_806R + P7_1N_806R (Caporaso et al, 2012;Moll et al, 2018) for the bacteria, and P5-5N-ITS4 (Gardes and Bruns, 1993;Leonhardt et al, 2019)/P7-4N-fITS7 (Ihrmark et al, 2012;Leonhardt et al, 2019) for the fungi, all containing the Illumina adapter sequences (see Supplementary Table S2 for an overview of the utilized primer sequences according to Hendgen et al, 2018). All PCRs were conducted using the proofreading KAPA Hifi polymerase (Kapa Biosystems, Boston, MA, United States).…”

Chemical composition of material extractives influences microbial growth and dynamics on wetted wood materials

“…Brown rot, associated with members of Fomitopsidaceae, results from the breakdown of the structural compounds cellulose and hemicellulose by fungal enzymes and alters the wood into shrunken, brown-discolored cubical pieces 65 . Differing from Fomitopsidaceae, certain species of Meruliaceae and Schizophyllaceae families cause another form of wood rot called white rot, wherein the lignin of moist wood is broken down, leaving behind a stringy, light-colored material composed mostly of undigested cellulose 66,67 .…”

Characterization and variation of bacterial and fungal communities from the sapwood of Apulian olive varieties with different susceptibility toXylella fastidiosa

“…In agreement with previous data [78,79], 87.5% of the retrieved isolates were found belonging to the phylum Ascomycota. At orders level, fungal endophytes in olive sap were prevalently defined belonging to Pleosporales, Eurotiales, and Phaeomoniellales, which is relatively common among the sapwood of different plants [80][81][82][83][84]. In the context of endophytic fungal relative density, few genera were more found colonizing Leccino's sapwood compared to other olive varieties.…”