The first report of Choiromyces venosus and a new report of Tuber aestivum from north Hyrcanian forest of Iran

Luxurious truffles have always been among the most popular symbiotic microorganisms, but there have been limited efforts to identify specific truffle species in forest systems around the world. Recent developments in molecular techniques have rapidly improved our ability to identify microorganisms responsible for the formation of truffles with different tree species. In the present study, an attempt was made to identify and describe two species of truffles occurring in deciduous forests of Golestan and Mazandaran provinces of Iran. Choiromyces venosus and Tuber aestivum were identified by a combination of morphological characterization, cytological methods and molecular analysis. Molecular characterization was performed by amplification and sequencing of the internal transcribed spacer regions (ITS) of nuclear rDNA. Based on the ITS sequences, Iranian specimens were placed in the same branch in a clade with T. aestivum and C. venosus. All sequences of C. venosus and T. aestivum, including the Iranian specimens, had an average similarity of 99.5% (the range was from 99 to 100%). Moreover, the diverse forests of Iran are a rich habitat for the ectomycorrhiza of truffle fungi. Due to the wide range of climatic conditions and forest communities in Iran, further studies are needed on the identification, diversity, ecology, phylogeny and economic value of Iranian truffles.