This invention provides strains of commercial mushrooms whose genetic material comprises genes from more than one species. These strains include a novel strain of the commercial mushroom genus Agaricus which is a cellular hybrid produced by fusion between protoplasts of two different Agaricus species. In another embodiment, this invention provides improved strains for commercial production of mushroom fruit which are progeny from crosses of Agaricus sp. with a cellular hybrid produced by fusion between protoplasts of two different species of the genus Agaricus.
