Figure 3.

The truffles (Tuber spp.) are demonstrated examples of mycorrhizal fungi that also are endophytic in roots of plants where they do not form mycorrhizae. (A) An endophytic Tuber melanosporum hypha (orange) in a Geranium sp. root (grey background), coloured by fluorescence in situ labelling as in Schneider-Maunoury et al. (2020). (B) Mycorrhizal pelotons of T. aestivum in an Epipactis microphylla orchid mycorrhiza (thin section under light microscopy, prepared as in Selosse et al., 2004). (C) An ectomycorrhiza of T. melanosporum, with hyphae covering the tip of a Quercus pubescens root (courtesy François Le Tacon, INRAe).