Scientists reveal the sex wars of the truffle grounds

Oct 25, 2010
Truffle from Mont-Ventoux. Image: Wikipedia.

They are one of the most highly prized delicacies in the culinary world, but now scientists have discovered that black truffles are locked in a gender war for reproduction. The research, published in New Phytologist as the truffle season begins, represents a breakthrough in the understanding of truffle cultivation and distribution.

The teams, led by Dr Francesco Paolocci and Dr Andrea Rubini from the CNR Institute in Perugia and by Dr Francis Martin from INRA in Nancy, carried out their research on the reproduction strategy of the highly prized black , Tuber melanosporum, which is grown across southern Europe. During the truffle season, between late autumn and winter, fruiting truffles can grow up to 7cm in diameter, weighing up to 100g with a value often measured in hundreds of Euros.

'Fruiting' is the crucial part of the truffle life cycle, occurring when the fungi interacts with and colonises host plants, usually at the roots. However, the process which causes this transition from vegetative to reproductive state remains unknown.

"It is commonly believed that truffles, like other fungi, are homothallic, meaning that they reproduce themselves," said Paolocci. "Because fungi that reproduce this way do not need a sexual partner it was believed that truffle cultivation relied only on the environment and nutrition, now we know that is wrong."

Taking advantage of the information provided by the T.melanosporum genome sequencing project led by Martin and from molecular analyses carried out by the Italian team, research now proves that truffles do outcross, meaning they are a two gender species, with sexual reproduction occurring between strains of opposite mating types.

The team studied samples of wild black truffle strains on plants from a natural truffle ground near Spoleto in central Italy. The study revealed that black truffle strains of opposite gender were not evenly distributed beneath potentially productive soil patches.

The team then studied the dynamics of truffle strains on host plants, artificially inoculated with truffle spores and grown in a greenhouse, which showed that a competition occurs between strains to colonise the host plant roots even under controlled conditions.

The truffle fruiting season traditionally begins in late autumn but is believed to occur in spring. The Italian team demonstrated that during the latter season strain of opposite gender are present in the soil samples next to colonised host plants and that the host plant colonising strain acts as maternal partner in the reproductive process.

These findings represent a breakthrough in the understanding of truffle reproduction tactics as well as the dynamics of black truffle strains in both open-field conditions and on produced to boost truffle production.

"These results are of considerable practical use for optimising and increasing production in truffle fields," concluded Paolocci. "It is of paramount interest to artificial truffle plantations to encourage a balance of strains of both mating types. Future investigations will allow us to determine whether the distribution of mating types is a factor that truly limits truffle fruiting body production."

Explore further: Lights, camera, blossom! Disney films inspire floral fantasy

Related Stories

Scientists scent breakthrough in truffle trafficking

Mar 28, 2010

One of Europe's gastronomic jewels, the fabled black Perigord truffle, has been genetically unravelled, a feat that could doom fakers who pass off inferior truffles as the real thing, scientists said on Sunday.

Sony Ericsson Intros New Cyber-Shot Phone

Aug 14, 2007

Sony Ericsson’s new K770 Cyber-shot phone, announced today, is a digital camera, a photo album and an elegant phone all in-one. Still a phone first and foremost, it allows you to send and share your photos ...

Recommended for you

A molecular compass for bird navigation

7 hours ago

Each year, the Arctic Tern travels over 40,000 miles, migrating nearly from pole to pole and back again. Other birds make similar (though shorter) journeys in search of warmer climes. How do these birds manage ...

100,000 bird samples online

9 hours ago

The Natural History Museum (NHM) in Oslo has a bird collection of international size. It is now available online.

New genetic technologies offer hope for white rhino

11 hours ago

With support from the Seaver Institute, geneticists at San Diego Zoo Institute for Conservation Research are taking the initial steps in an effort to use cryopreserved cells to bring back the northern white rhino from the ...

User comments : 0

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.