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A new species, Hypocrea atroviridis, is described for the teleomorph of Trichoderma atroviride. Based on sequences of ITS-1, 5.8S, and ITS-2 regions of the rDNA complex and translation-elongation factor (EF-1α), T. atrovirideand H. atroviridisform a well-supported clade within Trichodermasect. Trichoderma. The conserved anamorphic phenotype of T. atroviride, observed for both conidial and ascospore derived cultures, was only found within that clade. In contrast, the teleomorph phenotype of H. atroviridiswas morphologically indistinguishable from H. rufa, the teleomorph of T. viride. This Hypocreaphenotype may, therefore, be considered to be plesiomorphic within Trichodermasect. Trichoderma, suggesting that genes controlling the expression of the teleomorph and anamorph evolve at different rates and that the genes controlling expression of the teleomorph are more conserved than are those controlling the expression of the anamorph.

Forty‐four Trichodermastrains from water‐damaged building materials or indoor dust were classified with chromatographic image analysis on full chromatographic matrices obtained by high performance liquid chromatography with UV detection of culture extracts. The classes were compared with morphological identification and rDNA sequence data, and for each class all strains were of the same identity. With all three techniques each strain – except one – was identified as the same species. These strains belonged to Trichoderma atroviride(nine strains), Trichoderma viride(three strains), Trichoderma harzianum(10 strains), Trichoderma citrinoviride(12 strains), and Trichoderma longibrachiatum(nine strains). The odd strain was identified as Trichoderma hamatumby morphology and rDNA sequencing, but not by image analysis as no reference strains of this species were included. It is concluded that the secondary metabolite profile contains sufficient information for classification and species identification.

The identity of strains identified as Trichoderma aureoviride/Hypocrea aureoviridis was reconsidered. Trichoderma aureoviride was isolated originally from a specimen identified as H. aureoviridis and thus is H. aureoviridis. The morphological and molecular characters of most strains identified as T. aureoviride differ from those of the ex-type but are more typical of T. harzianum, a member of sect. Pachybasium. Molecular data do not support inclusion of T. aureoviride in sect. Trichoderma, nor was there strong phenotypic similarity between H. aureoviridis and H. rufa. In the ITS phylogeny the T. aureoviride ex-type and other collections of H. aureoviridis form a strongly supported clade that is separate from any other recognized section of Trichoderma. Hypocrea vinosa, which was originally included in the T. aureoviride aggregate species concept, is distinct from T. aureoviride, but closely allied with H. rufa/T. viride. Trichoderma aureoviride/H. aureoviridis is a rare species, restricted to the UK and the Netherlands. We redefine T. aureoviride, limiting it to strains with very slow growth rate, effuse conidiation, and the ITS-1 and 2 sequence type D.

AbstractThree new strains of Trichoderma reesei, the anamorph of Hypocrea jecorina, are reported from soil in French Guiana and Brazil. Identification of the strains as T. reesei/H. jecorinawas confirmed by analysis of the internal transcribed spacer regions 1 and 2 of the nuclear rDNA cluster and by their ability to produce the teleomorph when mated with the appropriate strains. Hypocrea jecorinais considered to reproduce primarily sexually, as opposed to other Hypocreaand Trichodermaspecies where asexual reproduction predominates. Like the original isolate of T. reesei, QM 6a, all three new isolates exhibited cellulolytic activities. In contrast to QM 6a, however, they grew on sucrose as sole carbon source and on nitrate as sole nitrogen source, thus indicating that these substrate utilization criteria are not taxonomically reliable in Hypocrea(Trichoderma). The nonutilization of sucrose and nitrate in QM 6a is due to a lack of the uptake system for sucrose and of nitrite reductase activity, respectively, in that culture. Comparison of QM 6a and the three new isolates revealed that all H. jecorinaisolates produce intracellular but not extracellular invertase. The potential for using these strains in the improvement of the commercially exploited strain of T. reesei, QM 6a, is discussed.

PCR-fingerprinting with primers (GACA)4, (GTG)5, M13 (core sequence of phage M13), and OPB-05 was used to compare ex type strains of various species of Trichoderma. The ex type strain of each species was obtained from different culture collections. PCR-fingerprints of each ex type culture, despite of separate cultivation over a long period of time (sometimes decades) by different culture collections, were identical. Ex type strains could be discriminated from a number of other strains belonging to the same species, since every strain was characterized by its individual PCR-fingerprint. PCR-fingerprinting is recommended as a basic tool for proving the identity of strains, especially with regard to comprehensive culture collections. Investigations of Trichoderma todica, a species of undefined systematic position within the genus Trichoderma, suggest a close relationship to Trichoderma parceramosum. Morphological and molecular data indicate that Trichoderma todicaand Trichoderma parceramosumare conspecific.

AbstractVariation within the internal transcribed spacer (ITS-1 and ITS-2) regions of ribosomal DNA of 103 strains was studied to examine relationships within Trichodermasect. Longibrachiatumand related teleomorphs, Hypocrea schweinitziiand H. jecorina.The four species, T. longibrachiatum, T. pseudokoningii, T. parceramosumand T. citrinoviride, that were originally assigned by morphological criteria to this section were recognized by sequence analysis. Trichoderma reesei, which was previously considered to be synonymous with T. longibrachiatum, and T. saturnisporumwhich was placed originally in sect. Saturnisporumbecause of its warted conidia, are assigned to the section. ITS sequences of T. ghanense, originally assigned to sect. Saturnisporum, could not be distinguished from the sequence of T. parceramosum, indicating that the two may be synonymous. Trichoderma “todica”, an unpublished name based on the antiviral strain NRRL 3091, is T. parceramosum.Interspecific variability within sect. Longibrachiatumwas low (2.2-4.8% in ITS-1, 0–10.2% in ITS-2) when compared with species of other sections. Phylogenetic analysis showed strong support for the monophyly of sect. Longibrachiatum.The Hypocreateleomorphs with anamorphs that could be assigned to sect. Longibrachiatumfall into at least 6 in part geographically defined groups on the basis of ITS sequences. The anamorphs of three of these groups can be assigned to T. longibrachiatum, T. citrinoviride, and T. pseudokoningii, respectively. Variability among these teleomorph groups is in the same order of magnitude as among the six anamorph species of sect. Longibrachiatum. Hypocrea jecorinaand T. reeseishowed 100% sequence homology. Classification derived from ITS sequences is discussed in comparison with results from other molecular methods.

Random amplification of polymorphic DNA (RAPD), using both fingerprinting (M13, [GTG]5, [GACA]4) and random [V5] primers, has been used to analyse 145 isolates characteristic of Trichoderma sect. Longibrachiatum and Hypocrea species with anamorphs referable to that section, and to identify strains with named species of sect. Longibrachiatum. To this end, ex-type strains of T. longibrachiatum, T. pseudokoningii, T. citrinoviride, T. parceramosum and T. reesei were analysed, and the similarity coefficients of RAPD characters used as a criterion for the alignment of strains to individual species. The ex-type strains of T. saturnisporum and T. ghanense exhibited the same interspecific similarity index as the other ex-type strains of Trichoderma sect. Longibrachiatum, and clustered well within it and were therefore included into this section. 103 isolates were identified as members of Trichoderma sect. Longibrachiatum and further investigated. Most of the anamorphic isolates could be aligned with T. citrinoviride or T. longibrachiatum, whereas only a few strains of T. saturnisporum and T. parceramosum were found. No naturally occurring anamorphs with homology to the ex-type strains of T. reesei and T. pseudokoningii were found. While T. longibrachiatum and T. citrinoviride overlapped through much of their geographic ranges, the former was present in Africa and India but not in southeast Asia, while the reverse was true of the latter. The African strains of T. longibrachiatum were equally distant from the ex-type strains of T. longibrachiatum, T. parceramosum and T. saturnisporum. The type strain of T. ghanense was identified as belonging to this group. T. pseudokoningii, the anamorph of Hypocrea schweinitzii, was found exclusively in eastern Australia and New Zealand. Attempts to identify potential teleomorphs of the other anamorphs revealed another subgroup of H. schweinitzii, occurring in temperate climates in Europe and U.S.A., as homologous to T. citrinoviride. No Hypocrea strains could be identified as teleomorphs of T. longibrachiatum, T. parceramosum or T. saturnisporum.

Forty-four Trichoderma strains from water-damaged building materials or indoor dust were classified with chromatographic image analysis on full chromatographic matrices obtained by high performance liquid chromatography with UV detection of culture extracts. The classes were compared with morphological identification and rDNA sequence data, and for each class all strains were of the same identity. With all three techniques each strain – except one – was identified as the same species. These strains belonged to Trichoderma atroviride (nine strains), Trichoderma viride (three strains), Trichoderma harzianum (10 strains), Trichoderma citrinoviride (12 strains), and Trichoderma longibrachiatum (nine strains). The odd strain was identified as Trichoderma hamatum by morphology and rDNA sequencing, but not by image analysis as no reference strains of this species were included. It is concluded that the secondary metabolite profile contains sufficient information for classification and species identification.