Ever wonder if your truffle orchard is reaching its full potential? Truffle-Typing™ can help. One factor to understand the production of truffles in the orchard is the mating type distribution. The truffle mycelium of a given species is characterized by two mating types, mat-1-1 and mat1-2. Both mating types can act as the maternal partner and can produce sporocarps. Additionally, both mating types can act as the paternal partner. Typically, maternal mycelium from one mating type dominates a given tree. The mating type distribution can vary across the orchard, and is thought to have significant effect on the ability of the paternal partner to cross with the maternal mycelium, resulting in truffle formation. An orchard dominated by a single mating type may suffer from suboptimal truffle production because of a lack of sufficient paternal mycelia and crossing potential. Truffle-Typing™ is a PCR based DNA test that can help understand the distribution of mating types in the orchard environment. This knowledge can help inform management decisions directed at increasing mating type diversity in the orchard. Clonal inoculum screened by Truffle-Typing™ allows us to supplement the orchard with mycelium of the limiting partner. Truffle traps are a traditional method of increasing and targeting truffle production in specific areas of the orchard.

Democratek is working on a PCR based test for determining mating type in truffles. Truffle fungi live in symbiosis with a number of species of trees, drawing carbohydrates from the roots in turn for supplying essential nutrients from the soil. Truffles are the fruiting body and reproductive spore dispersal mechanism for the truffle fungus. These subterranean fruits are relished by a number of mammals and birds, drawn by the seductive scent of the truffle. This prized fungus brings a high price in the market, and has generated great interest in cultivation for more reliable harvests. Early cultivation efforts are rudimentary. Most commonly, the spore slurry method is employed on young seedlings, with a truffle smoothie dripped or injected into the root system of the host plant. More modern mycelial cultivation methods employed broadly in the mushroom cultivation industry have been limited by the fastidious growth of truffle fungus in pure culture. Furthur, efforts to uncover details of the truffle reproductive cycle have revealed that truffle mycelia are heterothallic, or of two types, and must combine to form the reproductive structure of the truffle. Thus, in order for successful orchards to be established, two mycelial types must be present in the same orchard. For mycelial pure cultures to be used to generate productive truffle orchards, cultures of both mating types must be employed in the inoculation of truffle trees. Mating type genes have been identified in a few truffle trees, but tools to test the genotype of truffles, truffle trees, and truffle cultures have remained elusive. Democratek aims to develop a rapid Real-Time PCR assay, akin to the COVID PCR test, to analyze truffles, truffle cultures, and truffle tree roots for truffle mating type.
PCR is like Xerox for DNA, utilizing enzymes to make thousands and thousands of copies of DNA. Additional biotechnologies such as fluorescent dyes and synthetic DNA allow us to target DNA sequences unique to each mating type and cause the reaction tubes to glow when the specific DNA sequences accumulate. Genome analysis allows us to determine the specific sequences that we need to target and so we are able to develop this test for those truffle species with sequenced genomes. The first truffle that we are focusing our attention on is Tuber canaliculatum, or the Appalachian truffle. This truffle is a native American truffle, is highly regarded, and is extremely rare. Efforts to cultivate it are ongoing and early attempts suggest that it may be easier to grow native American truffles in the United States than it is to grow European truffles.
We will soon offer a Real-Time PCR test kit for use in determining mating type in Tuber canaliculatum and a PCR service for low volume testing.
 
If you would like to help further any of these projects, feel free to donate and note which project you wish to support.