Alternatively, it could be argued that Hygrocybe s.l. and Cuphophyllus spp. are more tolerant of the harsher climatic conditions of grassland habitats (large diurnal/seasonal fluctuations in temperature and humidity) from which even soil organisms are only partially insulated. This latter factor may explain why these species are often late-fruiting in European grasslands, a feature also found in Hygrophorus spp. Young (2005) suggested that shady forests and dense thickets in Australia
may provide a humid microclimate close to the ground. Despite stable isotope ratios that suggest that most Hygrophoraceae are biotrophic, a search of GenBank using BLAST searches
of ITS sequences from two species per clade found mainly Hygrophorus s.s. sequences from root tips (Online Selleckchem SHP099 Resource 2). A sequence of an unknown species was obtained from an unidentified bryophyte (GenBank AM999704, Kauserud et al. 2008) and similar ITS sequences were obtained from live Deschampsia grass roots (Poaceae) in the boreal zone (GenBank FJ517589— FJ517592, Abemaciclib Tejesvi et al. 2010, Online Resource 2). These root and moss associated sequences cluster near Chromosera in our ITS analysis (Online Resource 3), but support is low for placement in tribe Chromosereae (20 % MLBS in our analysis, Online Resource 3; 33 % MLBS in the analysis by Ercole, pers. com., 16 Nov. 2012). The ecology of the moss-grass root clade is more consistent with tribe Lichenomphaleae, and it might eventually be placed there once more gene regions have been sequenced and analyzed. BLAST Searches of GenBank (November 2012) using ITS sequences of two species per clade revealed many Cuphophyllus and Hygrocybe
sequences from soil or litter but not roots, which suggests they are neither mycorrhizal nor endophytic, though Persoh (2013) and Tello et al. (2013) has since presented evidence of Hygrocybe and Cuphophyllus as endophytes. A study of fungi in the rhizosphere next of Picea glauca in Canada by Lamarche, Seguin and Hamelin (unpublished, study described in Lamarche and Hamelin 2007, fungal sequences deposited in Genbank 2008), showed 5 clones of Hygrocybe cf. splendidissima (check details EU690689 and others), 26 clones of H. aff. punicea (GenBank EU690689 and others), 33 clones of H. chlorophana (EU690793 and others), >23 clones in the H. ceracea-H. insipida clade (EU690866 and others), and 39 clones of H. reidii (EU690490 and others). Little is known regarding transfer of plant compounds to rhizosphere fungi, though the fungal-specific Mrt gene in Metarrhizium robertsii was shown to function in transport of sucrose and raffinose-related oligosaccharides from root exudates (Fang and St. Leger 2010).