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Abstract
Truffles, like mushrooms, are the fruit of fungi. These fleshy organs are temporary reproductive structures that produce spores, which eventually germinate and give rise to new offspring. What sets truffles apart from mushrooms is that their spore-laden fruit forms below ground rather than above. Technically, true truffles are those fungi that belong to the Ascomycota phylum of organisms and are marketed as food.
Citation
Trappe, James M.; Claridge, Andrew W. 2010. The hidden life of truffles. Scientific American. April: 78-84.