Assessment of reproductive mode in Tuber melanosporum, the fungal species producing the most appreciated black truffles

Tuber melanosporum is an ectomycorrhizal ascomycete producing edible fruiting bodies, known as black truffles. Until recently, the prevalent view was that truffles strictly self, since genetic analyses had never detected heterozygotic profiles in their putatively diploid/ dikaryiotic structures. By using highly informative molecular markers such as SSR and SNPs, we have recently provided evidence for the prevalence of the haploid phase in the truffle life cycle and for the occurrence of outcrossing in both T. melanosporum and Tuber magnatum. Despite this new finding, however, the hypothesis of selfing is far from being settled. Here we took advantage of the recently published T. melanosporum genome and, by using a combination of bioinformatics and genome-based approach, we attempted to clone and characterized the second mating idiomorph in T. melanosporum.