Decay of Carpinus betulus wood by Trametes versicolor: an anatomical and chemical study

Decay patterns occurring in wood of hornbeam (Carpinus betulus) during natural decay in vivo were investigated and compared to decay in artificially inoculated wood in vitro. The fungal species causing decay was determined by morphological characterization and confirmed as Trametes versicolor using rDNA-ITS PCR and sequencing. T. versicolor caused degradation with properties of both simultaneous and selective white-rot. Chemical and FT-IR analyses suggested that T. versicolor caused severe reduction of lignin-carbohydrate complexes and guaiacyl lignin within the cell walls during natural decay. Under the light microscope, it was clear that decomposition of cell elements in the reaction zones of naturally decayed wood was greater than in inoculated wood. Histological analyses of inoculated wood blocks suggested that T. versicolor was able to switch from a typical simultaneous rot to selective delignification, with degradation of the middle lamella, and of lignin in cell corners. The results of our work demonstrated that test fungus able to attack the hornbeam tree by saprotrophic and parasitic life strategies.