Substrate preparation for Agaricus bisporus cultivation

ABSTRACT: Mushroom cultivation needs a selected organic substrate obtained during a composting process which is, in some aspects, quite different from the classical one. The aim is to analyse chemical and physical aspects of a composting process for mushroom cultivation in order to point out the peculiar characteristics, which enable a much faster preparation of the substrate. Raw materials were straw, chicken manure, gypsum and ammonium sulphate. In a very short time (11-13 days) the process led to a well-stabilised biomass, as it was shown by humification indexes, C/N ratio trend, organic carbon oxidation and ammonia nitrogen concentration decrease. In comparison to the classical composting procedure, a lower level of ammonia nitrogen and an organic nitrogen enrichment were present in the compost for mushroom cultivation. In addition, the high level of the substrate moisture, more than 75%, well above the limit normally recommended, has probably favoured the microbial growth rendering the process more efficient and faster.