Imagine you ordered a truffle at a fancy restaurant, and maybe you'll taste a very expensive raspberry from france or italy. However, in the past few decades, a new competitor has emerged in the truffle market. Today, one of the world's largest producers of black truffles (black truffles or perigor truffles) is not located in the northern hemisphere but in australia。
Since the introduction of truffles in australia some 25 years ago, production has increased year by year, making the country a major producer of perigor truffles outside europe, with more than 11 tons harvested annually from australian truffle plantations。
Black truffles have been bred in europe for a century and are the original species there. They were first introduced into australia in the early 1990s, when producers infected oak and other trees in the northern hemisphere with european truffles, and then sold and planted them in tasmania, victoria, new south wales and western australia。
Since then, the truffle industry in the country has developed and there are now more than 450 farms producing export truffles, with annual sales of about $30 to $40 million. Australia's truffle gardens are 20 times more productive than europe。
The truffle is a fungus that grows with the roots of certain trees. Fungi and roots form symbiotic relationships. The fungus filaments are wrapped and woven at the roots to help them absorb nutrients such as nitrogen and phosphorus, while fungi receive some nutrients from the sugar produced by trees during the photocooperative process。
Truffles are the fruit of fungus when they reproduce in plant roots. But it's not the only fungus that lives with plant roots. The truffle shares the underground home with many other species of fungus。
In order to find out where mushrooms live, a study team led by greg bonito and jan benucci of the faculty of botany, soil sciences and microbiology of the university of michigan analysed soil microbiodiversity in over 24 bacterial plantations in france, spain, italy and australia. The results were published in the journal applied and environmental microbiology。
At each sampling point, fungi scientists collected samples of the trees that had been vaccinated against truffles and the surrounding soil with spoons, which were then packaged for subsequent genetic analysis, and in two years some 522 samples were collected。
Dna sequences found that 4415 genetically different fungi were hidden in australian soils, compared to 6575 in european soils. In particular, the bacterial roots found in australian soil are 75 per cent smaller than in europe。
In addition, perigrine truffles are more common in australian soil than in european soil. It occupies a more monopolistic position in the symbiotic fungi underground。
Research suggests that, since the introduction of black truffles into australia, they have been able to develop rapidly, partly because they have emerged from natural enemies and competitors, and possibly because of other factors. They include climatic factors, water, cutting methods or some secret formulation of their care systems. Further research will focus on the analysis of microbiodiversity in truffle gardens in north america and other countries in the southern hemisphere to verify whether the patterns found exist。
The united states is known to have been the first country to successfully cultivate large-scale black truffles outside europe in the 1980s. Today, hundreds of farmers in the united states are engaged in truffle breeding. Overall, however, united states truffles produced less than australia. (source: michigan state university)
