Are there strains of Boletus edulis?

Boletus edulis has holes, and when the lid is opened, spores (the "seeds" of fungi) will be ejected. Boletus are all ectomycorrhizal fungi born with trees, so it is difficult to isolate strains and it is impossible to cultivate them artificially so far. Even if there is a strain, it can only be mycelium, and the fruiting body (mushroom) cannot be cultivated.