Litter quality control of decomposition of leaves, twigs, and sapwood by the white-rot fungus Trametes versicolor

Litter quality plays predominant roles in plant litter decomposition by modifying the activity of decomposer fungi, but little is known about the response of the decomposing activity of individual fungal strains to variations in litter quality. In the present study, the variability in the decomposing ability of a single fungal strain (Trametes versicolor IFO30340) was quantified under pure culture conditions to elucidate litter quality measures that control the decomposition. We used a total of 72 litters from 51 plant species, including leaves, twigs, sapwood, bark, heartwood, and petioles of broad-leaved trees, coniferous trees, and grass. Mass loss of litter caused by the fungus ranged from 0.9 to 59.8% of the original litter mass, was significantly higher in leaves, twigs, and petioles than in heartwood, and was significantly higher in broad-leaved than in coniferous litter. Tissue type (leaf, sapwood, or twig) and the relative amount of acid-unhydrolyzable residues to total nitrogen were selected as predictor variables of the mass loss of litters. Fourier transform infrared (FT-IR) spectroscopy showed that guaiacyl units of lignin negatively affected the fungal decomposition.