Mycorrhizal competition release and microbial dynamics innative and non-native Tuber melanosporum habitats

Benucci, Gian Maria Niccolò ; Garcia-Barreda, Sergi ; Sanchez, Sergio ; Marco, Pedro (Universidad de Zaragoza) ; De Miguel, Ana Maria ; Le Tacon, Francois ; Marozzi, Giorgio ; Baciarelli Failini, Leonardo ; Eslick, Harry ; Elliott, Todd F. ; Deveau, Aurelie ; Murat, Claude ; Donnini, Domizia ; Bonito, Gregory

Resumen: Truffles in the genus Tuber (Pezizales) are among the few ectomycorrhizaltaxa successfully cultivated worldwide. Australia has recently become one of the topproducers of Tuber melanosporum, a high-valued black truffle native to Europe. Truffleco-introductions in the Southern Hemisphere with their Northern Hemisphere plantsymbionts are hypothesized to benefit from reduced ectomycorrhizal competition andnatural enemies. In this study, we tested whether T. melanosporum in Australia experiences competition release by sampling soils and truffles across France, Spain, Italy,and Australia. Fungal and prokaryotic communities in truffle plantations were assessedin native (European) and non-native (Australian) habitats through ITS and 16S rDNAamplicon sequencing from soil and truffles. Community composition was primarilystructured by site of origin and secondarily by presence of brûlé, vegetation-free areainduced by truffle production of plant-growth inhibiting compounds, with significantinteractions indicating site-dependent brûlé effects. European soils showed higherfungal richness outside the brûlé, with higher evenness overall and for ectomycorrhizalfungi only outside brûlé. T. melanosporum showed higher abundance in Australia, withsignificant differences restricted to outside the brûlé. Overall, ectomycorrhizal fungi inEuropean soils had more than four times the taxa and higher diversity compared toAustralian soils. Among the main competitors, Tomentella, Inocybe, and Trichophaeaco-dominated in Europe, versus Scleroderma, Hebeloma, and Tarzetta in Australia. Despitedifferences in soil microbiomes, bacterial communities within T. melanosporum truffleascocarps were strikingly similar across sites and continents and were dominated byBradyrhizobium. Despite high site-level variation, our results support the competitionrelease hypothesis, with reduced enemies benefiting T. melanosporum colonizationoutside the brûlé in Australia. IMPORTANCE: This study provides the first cross-hemisphere analysis of the truffle microbiome, comparing native and non-native soils and truffles from Europeand Australia. We demonstrate that the remarkable success of Tuber melanosporumcultivation in Australia is compatible with ecological release from competitors, whichfavors its development outside the brûlé. At the same time, we reveal strikingcross-hemispheric similarities in truffle-associated bacterial communities, consistentlydominated by Bradyrhizobium. These findings highlight both the novelty and transcontinental relevance of our work, offering new perspectives on fungal ecology and trufflecultivation.

Idioma: Inglés

DOI: 10.1128/aem.00225-26

Año: 2026

Publicado en: Applied and Environmental Microbiology (2026), [21 pp.]
ISSN: 0099-2240

Tipo y forma: Artículo (Versión definitiva)

Área (Departamento): Área Nutrición Bromatología (Dpto. Produc.Animal Cienc.Ali.)