this most intensively cultivated mushroom, presents high-technology cultivation systems and growing particularities as the development of fruit bodies requires a nonnutrirional layer of casing soil on top of the nutritious compost. The mushroom mycelium grows into the casing layer in similar conditions to those of compost colonization, and when it reaches the upper surface of the casing layer the fruiting process starts through environmental manipulation comprising reduction of the temperature and the concentration of carbon dioxide through aeration to trigger fructification and to favor the development of mushrooms. the first pin initials begin to appear about 2 weeks after casing. From one layer of compost, two to three