Is the Distribution of Two Rare Orchis Sister Species Limited by Their Main Mycobiont?

As orchids rely on their mycorrhizal fungi for nutrient supply, their spatial range is dependent on the distribution of orchid mycorrhizal (OM) fungi. We addressed possible correlations between mycorrhizal specificity and the geographic distribution of orchids and OM fungi in three populations of the rare sister species Orchis patens and O. canariensis. Metabarcoding of the fungal ITS2 region indicated that, although adult plants of either species were colonized by several ceratobasidioid, tulasnelloid, sebacinoid and serendipitoid fungi, the mycobiont spectra were dominated by Tulasnella helicospora (which occurred in 100% of examined plants with high read numbers), which is a globally distributed fungus. In vitro assays with a T. helicospora isolate obtained from O. patens indicated the effectiveness of this OM fungus at germinating seeds of its native host. At a local scale, higher read numbers for T. helicospora were found in soil samples collected underneath O. patens roots than at locations unoccupied by the orchid. Although these findings suggest that the geographical pattern of the main fungal symbiont does not limit the distribution of O. patens and O. canariensis at this scale, the actual causal link between orchid and OM fungal occurrence/abundance still needs to be better understood

An interactive tool for the identification of airborne and food fungi

The growth of fungi may result in several kinds of food-spoilage: off-flavours, discolouration, rotting and formation of pathogenic or allergenic propagules. Moreover many foodborne fungi produce mycotoxins and thus fungal growth in foods and feeds should be avoided. Much interest has also grown for the fungi present in indoor environments, since exposure to airborne biological agents in both the occupational and residential environments could be associated with a wide range of adverse health effects with major public health impact, including infectious diseases, acute toxic effects, allergies and cancer. An interactive identification tool was created for food- and airborne microfungi at the genus and/or species level, based on morphological and physiological data, using the software FRIDA. The interactive key can also be stored on CD- or DVD-roms, or used on media such as PocketPCs of Smartphones. Our key allows the identification of 59 genera/groups and 217 species belonging mainly to Zygomycota and anamorphic and teleomorphic Ascomycota. The database comes with a set of detailed descriptions of each genus and species, a rich archive of images, a glossary of the most frequent mycological terms, and references to descriptions; in addition, culture condition requirements for identification are provided