The wood colonising white-rot basidiomycete Ceriporiopsis subvermispora is able to degrade lignin in preference to cellulose. To differentiate between fungal strains and to estimate their delignification behaviour, both in an early stage of degradation and over a specific period, is important for the wood industry. Mid infrared (MIR) and near infrared (NIR) spectra were taken from 60 milled spruce wood samples and their total lignin content was determined by wet laboratory methods. Good correlations were found between the MIR band-height ratio (H1510 cm -1 / H897 cm -1 ) and the lignin content (r = 0.965) and between the NIR band height at 5978 cm -1 (1673 nm) taken from spectra in the second derivative mode and the lignin content (r = 0.956). Furthermore, good linear correlations between the band-height ratios calculated from the MIR spectra and the amplitudes of the band around 5978 cm -1 (1673 nm) of NIR spectra in the second derivative mode were found for the calibration samples (r = 0.934) and for the fungal-treated samples (r = 0.984). The good correlation found between the MIR band-height ratio and the band height from NIR spectra in the second derivative mode could be interesting if calibrations exist for MIR (or NIR) to predict samples measured in the NIR (or MIR). MIR and NIR spectra recorded from milled spruce wood shavings that had been subjected to fungal treatment with three strains of Ceriporiopsis subvermispora (CBS 347.63, FPL 90.031 and FPL 105.752), for a period of up to 14 days, were investigated to see if these spectroscopic techniques could replace chemical methods. It is shown that the relative degree of delignification can be obtained directly from NIR spectra in the second derivative mode measuring the amplitude of a distinct band and from MIR spectra normalised with respect to the band at 897 cm -1 . Subjecting the spectra to principal component analysis (PCA) made it possible to study the time course along a PC axis. The use of an appropriate NIR wavenumber range subjected to PCA led to a scores plot that made it possible to differentiate between the three strains of C. subvermispora along one axis. It was also possible to give a time course and an indication of the relative degree of delignification along the second axis. In both cases, 99% of the data variance was explained with the first two PCs. A similar time course was obtained from MIR spectra, but the strains could not be separated well. Besides strain differentiation and examination of delignification, some practical applications (for example, in the pulp and paper industries, fungi-screening, evaluation of wood preservatives) are discussed. The results clearly demonstrate that it is possible to compare and differentiate between the strains without applying time-consuming chemical methods. The examination of NIR spectra is sufficient.

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Seven new species of Trichoderma, isolated from soil or tree bark from Siberia, Nepal, northern India, Taiwan, Thailand, Cambodia, and Malaysia, are described based on morphological and physiological characters, and from their phylogenetic position inferred from parsimony analyses of nucleotide sequences of the internal transcribed spacer (ITS) regions of the rDNA cluster (ITS1 and 2) and partial sequences of translation elongation factor 1-alpha (tef1α). Trichoderma sinensis sp. nov. and Trichoderma effusum sp. nov. are additions to Trichoderma section Longibrachiatum. Trichoderma helicum sp. nov., Trichoderma rossicum sp. nov., Trichoderma velutinum sp. nov., and Trichoderma cerinum sp. nov. are additions to section Pachybasium. Trichoderma erinaceum sp. nov. is described in section Trichoderma. The contribution of sequence data in resolving species in Trichoderma is demonstrated by Trichoderma helicum, which is morphologically indistinguishable from Trichoderma tomentosum Bissett, even though the two species are not phylogenetically closely related.Key words: Hypocrea, systematics, taxonomy, phylogeny.

Wood is colonised and degraded by a variety of microorganisms, the most efficient ones are wood-rotting basidiomycetes. Microbial decay processes cause damage to wooden constructions, but also have great potential as biotechnological tools to change the properties of wood surfaces and of sound wood. Standard methods to evaluate changes in infected wood, e.g., EN350-1 1994, are time-consuming. Rapid FT-NIR spectroscopic methods are also suitable for this purpose. In this paper, degradation experiments on surfaces of spruce (Picea abies L. Karst) and beech (Fagus silvatica L.) were carried out with white rot basidiomycetes or the ascomycete Hypoxylon fragiforme. Experiments with brown rot or soft rot caused by Chaetomium globosum were also performed. FT-NIR spectra collected from the degraded wood were subjected to principal component analysis. The lignin content and mass loss of the specimens were estimated based on univariate or multivariate data analysis (partial least squares regression).