
Truffles in Richereches, France. The blacker the cut truffle, the higher the quality. (Molly Moore/The Washington Post)
The mysterious black truffle has long eluded mushroom cultivators. It grows only in certain locations and can be extremely difficult to locate, and scientists have struggled to make it reproduce.
Its rarity has led to its popularity: A single ounce of truffle shavings — called the “black diamond,” — can cost as much as $100.
At long last the mystery has been resolved: The black truffle was sexually frustrated all along.
Unlike most fungi, which can self-fertilize, the black truffle is either a male or a female and can reproduce only in partnership. This discovery back in March gave hope that truffles could be bred, cutting the cost and making them more available to hungry mushroom lovers.
The thought was oak tree roots, where truffles are typically found, must be populated with truffles of the two sexes, and viola, more truffles for everyone. However, this proved not to be the case. Truffles seem to prefer to grow in single-sex clusters, and even ground that has been planted with a mixed colony is quickly dominated by one sex.
To reproduce, spores, then, must travel to other colonies on the backs of animals and insects. They can easily be lost along the way, missing the mating mark.
Francesco Paolocci and Andrea Rubini discovered the two-sex nature of the mushrooms during research at the Plant Genetics Institute in Perugia, Italy, the Telegraph reports. Growers will need to use the new discovery to plan single-sex truffle colonies that are close enough to be easily fertilized.
Don’t start planning your truffle supper soon, though. A truffle crop takes about six to 10 years to cultivate.