G. Di Massimo

Species-specific primers for the identification of the ectomycorrhizal fungus Tuber macrosporum Vittad

Limitations in the use of morphological traits to identify ectomycorrhizae have led to the development of species‐specific molecular markers. Herein, we report a PCR‐based technique for the reliable molecular identification of the ectomycorrhizal fungus Tuber macrosporum Vittad. Species‐specific primers were designed from an alignment of internal transcribed spacer rDNA sequences from Tuber spp. and from the most common ectomycorrhizal contaminants found in the root systems of truffle‐infected plants. The primers were tested for selective amplification using both different truffles and different ectomycorrhizae and were found to identify T. macrosporum successfully. The application of the primers in certifying the quality of truffle‐inoculated seedlings is discussed.

Effect of Sphaerosporella brunnea mycorrhizas on mycorrhization of Quercus ilex × Tuber melanosporum

Abstract It is generally accepted that Sphaerosporella brunnea is a significant ectomycorrhizal contaminant in nurseries producing plants mycorrhized with various species of Tuber, and subsequently in truffières after outplanting. At the University of Alcalá, Spain, 397 small plants of Quercus ilex which were mycorrhized with Tuber melanosporum were inadvertently contaminated with S. brunnea, and this contamination was then monitored for 2 years. Sixty percent of the plants were contaminated and had S. brunnea ascomata on the surface of the container on one or several occasions. However, a Spearman test provided no evidence that S. brunnea mycorrhizas affected T. melanosporum mycorrhization whereas other contaminating ectomycorrhizal fungi significantly did. Therefore, it appears that S. brunnea is not detrimental to plants which are well mycorrhized with T. melanosporum.