Soil Properties in Natural Truffle (Tuber spp.) Habits in Golestan Province

This study was conducted to investigate the properties of soil in natural habitats of truffle fungi (Tuber spp.) in six selected sites located in Loveh forests of Golestan province. Sampling of tree roots was done in the area that the host of Tuber spp. was existed and most of the truffle was harvested from them. The Tuber fungus was identified by the ITSrDNA region and comparing its sequence with the nucleotide sequences of the Genbank database. To sample the soil around the roots, five soil samples were taken for each ecological unit and a compound sample was prepared after mixing. After preparing soil samples, the amount of pH, organic matter, total nitrogen, calcium carbonate, potassium, calcium, magnesium and soil phosphorus were measured. Tuber fungus was identified as Tuber aestivum. All T. aestivum fruiting bodies were present in soils with alkaline pH and low phosphorus concentrations. C/N ratios of soils were above ten, indicating a preference of T. aestivum for soils that are poor in the readily degradable nitrogen and high nitrogen content in soils can limit the development of mycorrhizae. Our inventory suggested that a higher Ca/Mg ratio could be favourable for T. aestivum fruiting. The K/Mg ratio was below two at all sites. Our results showed that, in Golestan province, host species other than Quercus spp. are also important in regard to the hosting Tuber species.