Overview of molecular methods for quick identification of Tuber species

Truffles represent a resource of great value all over the world. The various species are widespread and occupy various habitats. Methods to identify their value in terms of marketing, cultivation, and the ecological–forestal field are needed. The traditional classification of Tuber species is based on their morphology; nevertheless, the macroscopic and microscopic characteristics of the fruiting body, spores, and ectomycorrhizae may be absent or insufficiently discriminating. This problem is amplified when dealing with valuable truffle species, which are often replaced by truffles with lower organoleptic qualities and commercial value. Today, molecular biology can help to correctly identify them through several widely used methods that are fast, specific, and sensitive. Molecular methods are mostly PCR-based, with primers designed on various targets, genes, or regions widely variable between species but sufficiently conserved within the same species. The DNA regions analyzed for identifying truffles include ribosomal internal transcribed spacer (ITS), ribosomal large subunit (LSU), β-tubulin, and EF-α elongation factor. This review summarizes the main and most reliable DNA-based molecular methods for identifying Tuber species. The methods are listed schematically and clearly for quick consultation and use in all areas of study in which monitoring, and verification of the species is essential.