The objective of this work was to quantify and to isolate the bacteria present in casing layer used for the cultivation of the Agaricus blazei Murril. It was evaluated the efficiency of the steam and formaldehyde disinfestation in the casing layer. The formaldehyde disinfestation showed a reduction of the bacteria population on the ravine soils (distroferric Red Latosol) and grazing land soil (distrofic Yellow Latosol), while in the hydromorphic soil coming from lowland (Melanic G]/leysol) none of the treatments used were efficient to reduce the bacteria population. Bacteria of the genera Pseudomonas, Salmonella, Enterobacter, Shigella, among others, were identified in all treatments analysed. It was observed that the disinfestation treatments did not eliminate neither potentially beneficial bacteria nor pathogenic bacteria. There was no significant effect of the disinfestation treatments on productivity of A. blazei mushroom. Moreover, the disinfestation treatments did not affect the productivity of the A. blazei in the studied conditions.
Agaricus blazei; edible mushrooms; casing layer; disinfestation
