Truffles and agroforestry: a binomial to be explored, planned and spread.

Edible truffles, the hypogeous fruiting bodies of several species of the Tuber genus, are Ascomycetes fungi giving rise to mycorrhizal mutualisms with various forest species and within various ecosystems. In order to test the viability of truffle production in agroforestry, proper ecophysiological tools are needed. The potential tree-fungi relationship is critical in choosing the trees species and managing the soil to maximise the chance of truffle production. The main goal was to find the host trees through stable isotope methods. We applied a simplified interaction model, looking at the exchange of carbon (13C) and nitrogen (15N) by the fungi (Tuber aestivum) vs the host trees. A comprehensive geodatabase was developed in order to produce the maps of the spatial variability of the isotopic abundances and to trace an isotopic landscape (isoscape; West et al. 2010). Our conclusion is that establishing new mycorrhizal relationships is not easy in forest ecosystems. We foresee even worse conditions in an agroforestry managed farm, where truffle producing grounds have to cope with neighbouring agronomic disturbances. This work was supported by REALMed "Pursuing authenticity and valorization of Mediterranean traditional products", ERA-NET project, grant agreement no. 618127.