Rapid molecular typing method for the reliable detection of Asiatic black truffle (Tuber indicum) in commercialized products : fruiting bodies and mycorrhizal seedlings

Although authorized for the French market, the Asiatic black truffle, Tuber indicum, may potentially be sold as T. melanosporum, the ”Perigord black truffle’’, due to difficulties in distinguishing between them by morphological criteria. A molecular method using a DNA extraction kit and specific primers based on the interspecific polymorphism of the internal transcript spacer DNA region has allowed us to amplify T. indicum samples (mycorrhizas, fresh, dried, and frozen ascocarps) and even to detect as little as 1% of Asiatic truffle in a mixture of ground ascocarps or mycorrhizas containing T. melanosporum. Our process is specific, sensitive, convenient and quick, so it could be used for the rapid detection of T. indicum in non-cooked food products and commercialized mycorrhizal seedlings to avoid the ecological damage which would result from its accidental introduction.