Tuber wenchuanense, a holarctic truffle with a wide range of host plants and description of its ectomycorrhiza with spruce

Abstract

AbstractTuber wenchuanenseascomata (Ascomycota, Pezizales), a species originally described from Sichuan (China), were found in the Tatra Mountains in southern Poland. The purpose of this work was to (i) report and assess the first case of the holarctic natural distribution of aTuberspecies, (ii) amend the original description of the species, (iii) summarize data on its host plants and (iv) describe its ectomycorrhiza. Specimens ofTuber wenchuanensefrom the Tatra Mountains were studied morphologically and molecularly. The ectomycorrhiza of this truffle withPicea abieswas described for the first time. The distribution ofT. wenchuanense, which is reconstructed based on sequences deposited in the publicly available nucleotide sequence databases, makes it the first holarcticTuberspecies and the one with the northernmost habitat. In fact, its habitat is confined mainly to mountain coniferous forests and alpine and arctic tundra; although, according to known observations, the fruiting bodies ofT. wenchuanensecan be produced only under conifers. Based on the sequences of the internal transcribed spacer, this species appears to have low genetic variability over the entire distribution range. The phylogenetic tree showed that some of the unidentified phylotypes from the Rufum clade found by other researchers belong toT. wenchuanense. The ecological implications of these findings are discussed.