New Insights into the Complex Relationship between Weight and Maturity of Burgundy Truffles (Tuber aestivum)

PLoS One. 2017 Jan 26;12(1):e0170375. doi: 10.1371/journal.pone.0170375. eCollection 2017.

Abstract

Despite an increasing demand for Burgundy truffles (Tuber aestivum), gaps remain in our understanding of the fungus' overall lifecycle and ecology. Here, we compile evidence from three independent surveys in Hungary and Switzerland. First, we measured the weight and maturity of 2,656 T. aestivum fruit bodies from a three-day harvest in August 2014 in a highly productive orchard in Hungary. All specimens ranging between 2 and 755 g were almost evenly distributed through five maturation classes. Then, we measured the weight and maturity of another 4,795 T. aestivum fruit bodies harvested on four occasions between June and October 2015 in the same truffière. Again, different maturation stages occurred at varying fruit body size and during the entire fruiting season. Finally, the predominantly unrelated weight and maturity of 81 T. aestivum fruit bodies from four fruiting seasons between 2010 and 2013 in Switzerland confirmed the Hungarian results. The spatiotemporal coexistence of 7,532 small-ripe and large-unripe T. aestivum, which accumulate to ~182 kg, differs from species-specific associations between the size and ripeness that have been reported for other mushrooms. Although size-independent truffle maturation stages may possibly relate to the perpetual belowground environment, the role of mycelial connectivity, soil property, microclimatology, as well as other abiotic factors and a combination thereof, is still unclear. Despite its massive sample size and proof of concept, this study, together with existing literature, suggests consideration of a wider ecological and biogeographical range, as well as the complex symbiotic fungus-host interaction, to further illuminate the hidden development of belowground truffle fruit bodies.

MeSH terms

  • Ascomycota / growth & development*
  • Fruiting Bodies, Fungal / growth & development*
  • Hungary
  • Life Cycle Stages*
  • Soil
  • Switzerland
  • Symbiosis

Substances

  • Soil

Grants and funding

Supported by the WSL-internal DITREC project, the Ernst Göhner Foundation, as well as the Swiss State Secretariat for Education, Research and Innovation (SERI): COST Action FP1203. Moreover, U. Büntgen received funding from the Ministry of Education, Youth and Sports of CR within the National Sustainability Program I (NPU I), grant number LO1415., whereas R. Splivallo and M. Vahdatzadeh were supported by the LOEWE research-funding program of the government of Hessen, in the framework of the Integrative Fungal Research Cluster (IPF) and by the German Research Foundation (DFG) – grant number 1191/4-1. The UMR1136 is supported by a grant overseen by the French National Research Agency (ANR) as part of the "Investissements d'Avenir" program (ANR-11-LABX-0002-01, Lab of Excellence ARBRE). Truffleminers Ltd provided support in the form of salaries for authors [IB, OF], but did not have any additional role in the study design, data collection and analysis, decision to publish, or preparation of the manuscript. The specific roles of these authors are articulated in the ‘author contributions’ section. The funder provided support in the form of salaries for authors [UB, RS, MV, CM, IB, OF], but did not have any additional role in the study design, data collection and analysis, decision to publish, or preparation of the manuscript. The specific roles of these authors are articulated in the ‘author contributions’ section.