improvement of white button mushroom yield by aflp marker-assisted single spore selection method

the white button mushroom, agaricus bisporus, is a commercially important cultivated filamentous fungus. strain stability is of great importance to both spawn producers and mushroom growers. mushroom strains are usually propagated via vegetative method on nutritionally rich substrates. abnormal growth and poor yield ‎are the consequences of this replication method. the reason for this phenomenon is still unknown. the use of molecular markers is one way of assessing and understanding the genetic changes. in this study, for the first time we reported the application of amplified fragment length polymorphism (aflp) marker to assess genetic variation in single spore progeny and to assist selection of superior cultivars based upon the use of monosporous cultures of a. bisporus commercial strain, holland737. we isolated 30 single spores that differed in growth rate, productivity and aflp inheritance pattern. nine ecori / taqi primer combinations identified a total of 353 aflp bands from 19 single-spore isolates, of which 53 were polymorphic. results showed that the single spore selection is an effective method for strain improvement in a. bisporus, so that two isolates averagely performed 47% increased yield over the maternal strain and aflp showed enough sensitivity to detect polymorphisms among single spore isolates.