Black truffles are a unique type of fungi that are highly prized by chefs and food enthusiasts throughout the world. which characteristic is seen in truffles but not in common mushrooms?

The characteristic which is seen in truffles but not in common mushrooms is that it has spores contained in ascus.

Explanation:

Black truffle is a prized food item which is a fungi but different from common mushroom in several ways. Truffles grow underground and their whole lifecycle is completed under the ground itself. They live in close association with  some tree roots.

Truffle is indeed the fruit of a fungus called mycelium. Mycelium depends on the tree on whose root it lives to receive chlorophyll and in return to this favor the tree is supplied extra nutrients through the hyphal system.

In the fruiting phase the truffle becomes independent of the mycelium and derives nutrition in its own way using tiny filaments called hyphas. When the truffle withers underground,  spores get released which are stored in bags called ascus.

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