Truffle sex & what that means for orchard management & productivity by Shannon Berch

In this presentation, Dr. Sannon Berch reviews four scientific publications (see below) that are available for free download or on the NATGA web site under Resources, Papers. Although it is Shannon’s goal to make the science reasonably accessible for non-scientists, she is explaining biological and mycological phenomena and exploring hypothetical scenarios. The paper by Le Tacon et al. (2016) provides an explanation of what is known and still unknown about how truffle fungi reproduce. Since the end result of this reproduction is the truffle, it is important that truffle growers understand the basics. The paper by Garcia-Barreda et al. (2020) examines how soil and season affect truffle traits like weight and maturity, how the installation of ‘nests’ or ‘Spanish wells’ alters these responses, and how truffle traits and responses to nest installation differ in different soil types. Making sure there is genetic diversity in the truffle orchard through the application of spores (nests or Spanish wells) could be key to enhancing productivity but under what conditions? The paper by Iotti et al. (2016) explores how inoculation of seedlings in the nursery with mycelium rather than spores might permit the selection of truffle strains with superior characteristics. Only Tuber borchii at present lends itself to this kind of strain selection since it is much easier than most other Tuber species to grow in pure culture. We hope that by the end of this webinar, participants will have a better understanding of how truffles are produced and, using this understanding, be better able to evaluate possible future alterations to how truffles are cultivated.

Ascoma genotyping and mating type analyses of mycorrhizas and soil mycelia of Tuber borchii in a truffle orchard established by mycelial inoculated plants

Tuber borchii (the Bianchetto truffle) is a heterothallic Ascomycete living in symbiotic association with trees and shrubs. Maternal and paternal genotype dynamics have already been studied for the black truffles Tuber melanosporum and Tuber aestivum but not yet for T. borchii.

Variability and trends of black truffle production in Spain (1970-2017): Linkages to climate, host growth, and human factors

Black truffle (Tuber melanosporum) is a highly-appreciated fungus that grows below ground during several months, undergoing a series of morphogenetic stages before it is harvested in late autumn or winter. Black truffle production in Spain has been subject to important temporal variation in recent decades.

Edaphic and temporal patterns of Tuber melanosporum fruitbody traits and efect of localised peatbased amendment

In Tuber melanosporum cultivation, fruitbody traits are gaining relevance due to their increasing prominence on prices. We investigated the edaphic and temporal patterns of fruitbody traits and characterised the efect of trufe nests (localised peat-based amendment supplemented with T. melanosporum spores) on traits.

Certainties and uncertainties about the life cycle of the Périgord black truffle (Tuber melanosporum Vittad.)

Several aspects of the life cycle of the Périgord black truffle have been elucidated only recently, while others remain either controversial or unstudied. In this paper, we present a revised life cycle of this fungus and highlight key aspects that have yet to be addressed or require further understanding.

The need for proper edible mycorrhizal fungi (EMF) cultivation trials: How plantation management impacts yields by Dr. Alexis Guerin

Knowing how plantation management affects the yield of edible mycorrhizal fungi (EMF) is both a new and complex issue. We are virtually inexperienced compared to most other horticultural sectors. EMF production also relies on the symbiotic interaction with host trees. The variable success obtained with truffle cultivation worldwide speaks for itself: a true cultivation remains to be invented. The current lack of knowledge is also a great research opportunity: so much can be learned if only we invest in it. Since no research work has yet addressed this question on truffles, I will present the monitoring of the yield of a mycorrhizal mushroom: saffron milk cap.