Molecular studies on terricolous microfungi reveal novel anamorphs of two Tuber species

This study reports novel terricolous mitosporic fungal morphs nested in the genus Tuber according to molecular phylogenetic analysis. Fungal DNA was amplified directly from field-collected anamorph samples. Nuclear ribosomal DNA (nrDNA) sequences including the ITS regions and the D1 and D2 domains of the LSU identify the anamorphs as mitosporic Tuber borchii and Tuber oligospermum. The link of the novel anamorphs to the genus Tuber is confirmed by the comparative analysis of five collections from four sampling sites. Ectomycorrhizas with characteristic features of Tuber borchii ectomycorrhizas were found in the soil volume collected with one of the mitosporic T. borchii collections. A nrDNA sequence amplified from these ectomycorrhizae is identical with the corresponding anamorph sequence. The possible role of the newly discovered anamorphs in the Tuber life-cycle and the potential significance of anamorphs for the propagation of ectomycorrhizal fungi are discussed.