recycling of casing soil in the white button mushroom (agaricus bisporus) production

in this study, the recovery of casing soil consumed in the white button mushroom was investigated. casing soil is used as a layer on compost (culture medium) to a diameter of 3-5to stimulate fruiting on the white button mushroom(agaricus bisporus) . the expense od casing soil is about 30 percent of production costs. in the first step of this experiment, in order to separate casing soil from compost easily (at the end of production period),by distribution of a mesh with pores of 5 mm between compost and casing soil in the casing step, which we could separate and easily collect casing soil at the end. the most important altering factor between chemical and physical properties of recycling casing soil, is ec that was reduced by leaching process. an experiment was conducted based on split plot design with two factors and three replications. the main plots were treated with two levels of with and without a plastic mesh. percentages of recycled soils in combination with fresh casing soil applied in sub plots. subplot included 100%, 75%, 50%, 25% and 0% of recycled soil. three traits included fruit yield, fruit average weight and fruit number were analyzed using sas software. none of the traits showed significant differences. no significant difference was obsereved between with and without plastic mesh. further more no difference was observed between different percentages of recycled soil mixed with fresh peat. it is thus concluded that using recycled casing soil in production of the white button mushroom is possible and profitable.