Helping you grow truffles

With research projects spanning 23 countries, the majority of our results are held in-house and used to help advise those we are working with to grow truffles. This keeps our truffle cultivation partners (learn more about becoming a partner here) on the cutting edge. Select portions of our research are made public, by way of publication in academic journals and scientific conferences. A selection of these appear below. For further information or copies of papers, please do not hesitate to get in contact.

Understanding the performance of truffle dogs

NOTE: Research such as this allows us to guide you as to where is and isn't suitable for truffle cultivation, taking into account different climate change scenarios.

ABSTRACT: Trained dogs can detect many biochemical traces, from the most hostile, such as COVID-19, to the most expensive, such as truffles. However, it is still unclear how the interplay of genetic disposition, education, experience, personality, and environmental conditions influences the performance of dogs. Here, we combine published evidence with the knowledge of truffle hunters to assess direct and indirect factors that affect the hunting performance of truffle dogs. Since the transport of truffle aroma into the canine nasal cavity is most puzzling, we propose five experiments to further investigate the role of weather conditions, soil parameters, and bacterial composition on the dispersal of truffle volatiles perceived by trained dogs. We also suggest exploring whether the application of multiple dogs increases the success of truffle hunting. Moreover, we argue that interdisciplinary research on dog behavior and performance, including insights from veterinary science and comparative psychology as well as the experience of truffle hunters and farmers, is needed to improve the quantity and quality of truffle harvests.

Authors: Tomáš Cejka, Paul W. Thomas, Daniel Oliachd, Ulrich Stobbe, Simon Egli, Willy Tegel, Giada Centenaro, Ludger Sproll, István Bagii, Miroslav Trnka, Ulf Büntgen

Journal of Veterinary Behavior (2022). https://doi.org/10.1016/j.jveb.2022.04.002

Rethinking a sustainable truffle sector under global crisis

Abstract: Global climate change is the main threat for the emerging truffle sector, which already extends across seven key regions in the Americas, Europe, South Africa and Australasia. At the same time, the potential effects of financial crises and global pandemics have not yet been considered in most risk assessments. Here we describe the direct and indirect impacts of the actual coronavirus pandemic on the rising truffle sector. We discuss how COVID-19 affects small family businesses and international enterprises, and if the current harvest decline will have ecological long-term benefits. Furthermore, we question extant cultivation practices, irrigation techniques and trade systems to prepare for a more equitable and sustainable future of the global truffle industry. Despite various foci on one of the most expensive gourmet foods and its associated agroforestry, we expect our reflections to be valuable for many other high-value crops, and a green agriculture in general.

Keywords: biodiversity, COVID-19, economic crises, global pandemic, gourmet food, green-agriculture, irrigation systems, reforestation, rural economies

Authors: Büntgen, U., Tomáš, C., Mirek, T and Thomas, P. W.

Erdkunde (2021). https://doi.org/10.3112/erdkunde.2021.04.06

Ectomycorrhiza resilience and recovery to extreme flood events in Tuber aestivum and Quercus robur

Abstract: Very little is known about the impact of flooding and ground saturation on ectomycorrhizal fungi (EcM) and increasing flood events are expected with predicted climate change. To explore this, seedlings inoculated with the EcM species Tuber aestivum were exposed to a range of flood durations. Oak seedlings inoculated with T. aestivum were submerged for between 7 and 65 days. After a minimum of 114-day recovery, seedling growth measurements were recorded, and root systems were destructively sampled to measure the number of existing mycorrhizae in different zones. Number of mycorrhizae did not display correlation with seedling growth measurements. Seven days of submersion resulted in a significant reduction in mycorrhizae numbers and numbers reduced most drastically in the upper zones. Increases in duration of submersion further impacted mycorrhizae numbers in the lowest soil zone only. T. aestivum mycorrhizae can survive flood durations of at least 65 days. After flooding, mycorrhizae occur in higher numbers in the lowest soil zone, suggesting a mix of resilience and recovery. The results will aid in furthering our understanding of EcM but also may aid in conservation initiatives as well as providing insight for those whose livelihoods revolve around the collection of EcM fruiting bodies or cropping of the plant partners.

Authors: Thomas, P. W.

Mycorrhiza (2021). https://doi.org/10.1007/s00572-021-01035-4

Effect of flooding on truffle tree roots ectomycorrhiza

A risk assessment of Europe's black truffle sector under predicted climate change

ABSTRACT: The black truffle (Tuber melanosporum) is a highly revered culinary icon species that grows symbiotically with its host trees across several parts of southern Europe. Where harvested under natural or cultivated conditions, truffles can have a significant socioeconomic impact and may even form a key component of cultural identity. Although some aspects of truffle biology and ecology have been elucidated recently, the role of abiotic, environmental and climatic factors in the production and maturation of their fruitbodies is still largely unknown. Based on 36-year-long, continuous records of Mediterranean truffle yield, we demonstrate that decreased summer precipitation together with increased summer temperatures significantly reduce the fungus' subsequent winter harvest. Using state-of-the-art climate model projections, we predict that a significant decline of 78–100% in southern European truffle production is likely to occur between 2071 and 2100. The additional threats of forecasted heatwaves, forest fires, pest and disease outbreaks are discussed along with socioeconomic and ecological consequences of a warmer and dryer future climate. Our results emphasize the need for unravelling the direct and indirect effects of climate change on Europe's truffle sector and underline the importance of conservation initiatives at local to international scales.

Keywords: Climate change, Ectomycorrhiza fungi, Fungal ecology, Truffle yield, Tuber melanosporum, Périgord truffle.

Authors: Thomas, P. W and Büntgen, U.

Science of the Total Environment (2019).

https://doi.org/10.1016/j.scitotenv.2018.11.252

Risk and reward of the global truffle sector under predicted climate change

Abstract: Climate change has been described as the main threat for the cultivation and growth of truffles, but hydroclimate variability and model uncertainty challenge regional projections and adaptation strategies of the emerging sector. Here, we conduct a literature review to define the main Périgord truffle growing regions around the world and use 20 global climate models to assess the impact of future trends and extremes in temperature, precipitation and soil moisture on truffle production rates and price levels in all cultivation regions in the Americas, Europe, South Africa, and Australasia. Climate model simulations project 2.3 million km² of suitable land for truffle growth will experience 50% faster aridification than the rests of the global land surface, with significantly more heat waves between 2070 and 2099 CE. Overall, truffle production rates will decrease by ∼15%, while associated price levels will increase by ∼36%. At the same time, a predicted increase in summer precipitation and less intense warming over Australasia will likely alleviate water scarcity and support higher yields of more affordable truffles. Our findings are relevant for truffle farmers and businesses to adapt their irrigation systems and management strategies to future climate change.

Keywords: adaptation strategies, agricultural drought, climate models, irrigation systems, price estimates, production risk, truffle industry

Authors: Tomáš, C., Isaac, E. L., Oliach, D., Martínez-Peña, F., Egli, S., Thomas, P. W., Trnka, M and Büntgen, U.

Environmental Research Letters (2022). https://doi.org/10.1088/1748-9326/ac47c4

First harvest of Périgord black truffle in the UK as a result of climate change

Abstract: Although some truffle species are among the most expensive gourmet foods, much of their biology and ecology is still poorly understood. Here, we provide the first record of cultivation of the Périgord black truffle Tuber melanosporum in the UK − the most northern and maritime Périgord truffle ever cultivated. This raises hopes of counteracting the ongoing, long-term, drought-induced harvest decline of this gastronomic icon species in its natural Mediterranean habitat. More generally, we detail how the UK’s first Périgord truffle find may help protect this coveted and extremely valuable product from the impacts of ongoing and predicted global warming. Finally, we address the potential sizeable economic importance of black truffle cultivation in the northern maritime climate of the British Isles, which implies a strong financial incentive for a variety of conservation initiatives.

Keywords: Climate change · Truffle cultivation · Ectomycorrhiza fungi · Geographical distribution · Truffle ecology · Tuber melanosporum · Périgord truffle · UK

Authors: Thomas, P. W and Büntgen, U.

Climate Research (2017). https://doi.org/10.3354/cr01494

First black Perigord truffle (Tuber Melanosporum) produced in the UK

Truffles and mating types

Abbreviated abstract: Truffles are one of the most highly prized of all fungi. Recent advances and genetic studies have furthered our understanding of the mode by which these fungi reproduce. The understanding that some truffle species require a mating partner in order to produce fruiting bodies leads to many questions and opportunities in truffle cultivation. Here, a summary and analysis of the most recent work is presented. The potential applications of this understanding are discussed along with proposals for in-field modifications to improve the truffle yields of plantations.

Authors: Thomas, P. W

The role of soil pH

Abbreviated abstract: Here we present data from 22 sites across Europe relating soil pH to truffle mycorrhiza survivorship and development. Several data points are presented in detail and used as case studies. Utilizing the data from this study, the independent role of pH on mycorrhiza development as well as the interaction of pH and other factors, is observed. The importance that is placed on soil pH in commercial orchards is discussed.

The role of pH in Tuber aestivum/uncinatum mycorrhiza development within commercial orchards.