New insights into black truffle biology: discovery of the potential connecting structure between a Tuber aestivum ascocarp and its host root
According to isotopic labeling experiments, most of the carbon used by truffle (Tuber sp.) fruiting bodies to develop underground is provided by host trees, suggesting that trees and truffles are physically connected. However, such physical link between trees and truffle fruiting bodies has never been observed. We discovered fruiting bodies of Tuber aestivum adhering to the walls of a belowground quarry and we took advantage of this unique situation to analyze the physical structure that supported these fruiting bodies in the open air. Observation of transversal sections of the attachment structure indicated that it was organized in ducts made of gleba-like tissue and connected to a network of hyphae traveling across soil particles. Only one mating type was detected by PCR in the gleba and in the attachment structure, suggesting that these two organs are from maternal origin, leaving open the question of the location of the opposite paternal mating type.
KeywordsTruffle Tuber aestivum Ectomycorrhizae Symbiosis Fruiting body Anatomy Mating type
We are very grateful to the two reviewers who have greatly improved the text.
Conceived and designed the work: FLT, AD. Contributed reagents/materials/analysis tools: AD, PC, FP, JPM, FT, MH, JR, CM. Analyzed the data: AD, FLT. Wrote the first draft: FLT. Edited manuscript: FLT, AD, CM. All authors read and commented on the manuscript.
This work was funded by the Laboratory of Excellence Advanced Research on the Biology of Tree and Forest Ecosystems (ARBRE; ANR-11-LABX 0002 01).
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