食用菌种类繁多,不仅种与种之间,就是种内的个体间也没有完全相同的,这种个体差别叫变异。当栽培等条件相同而基因不同时,会出现变异;而基因相同、栽培等条件不同时,也会出现变异。前者叫可遗传的变异,后者叫不可遗传的变异。食用菌的选种育种,需要可遗传的变异,这就要排除因环境等栽培条件所引起的变异,去选择由基因改变所引起的变异。通常人们喜欢以大的菇型作为选种标准,但后代未必长出大型的菇,其中一个可能是菇型由多基因决定,而且基因发生分离所致,另一个可能是栽培等条件造成菇型的不可遗传 A wide range of edible fungi, not only species and species, is not exactly the same species within the individual, this individual difference is called mutation. When the cultivation conditions are the same while the genes are different, there will be variation; the same gene, cultivation and other conditions are different, there will be variation. The former is called heritable variation, the latter is called heritable variation. Edible mushroom breeding, the need for genetic variation, which should be excluded due to environmental conditions such as the variation caused by cultivation, to select the mutation caused by genetic variation. Usually people like to use large mushrooms as a selection criteria, but the offspring may not grow large mushrooms, one of which may be mushroom-based multi-gene decisions, and genetic separation caused by the other may be caused by the cultivation of mushrooms The can not be inherited