Lactarius ectomycorrhizae on Abies alba: morphological description, molecular characterization, and taxonomic remarks

To date, the ectomycorrhizae formed by silver fir (Abies alba), an ecologic ally valuable and indigenous tree species in many European mountain forests , have been poorly investigated. We characterized the mycorrhizae formed by three Lactarius species (Lac. subsericatus, Lac. intermedius, Lac. salmon icolor) On silver fir, on the basis of material originating from central It aly. The identification of the fungal symbiont was achieved by means of mor phoanatomical observations of mycorrhizae, and by comparison of ITS sequenc es obtained from mycorrhizae and sporocarps of putative fungal partners. Se quences also were obtained from specimens of the same species but from diff erent geographic origin or from closely related Lactarius species. A maximu m likelihood analysis of the data was performed. On the whole, the resultan t tree is in good agreement with sporocarp and mycorrhiza morphology. RFLP patterns were calculated from sequence data. A discussion on the main morph oanatomical characters distinguishing the Lactarius ectomycorrhizae reporte d in this study from those already described belonging to related species, is also included. The accuracy of different methods to identify mycorrhizae formed by closely related Lactarius species on silver fir, are discussed.