MYCELIUM GROWTH OF PLEUROTUS SPP. IN RICE STRAW SUPPLEMENTED WITH LEATHER SAWDUST

ABSTRACT The objective of this study was to evaluate the biomass production, mycelial growth and colonization of rice-straw substrate by Pleurotus ostreatus and Pleurotus ostreatoroseus under the effect of adding vegetable-tanned leather sawdust. The first experiment consisted of the formulation of the culture media based on rice straw with the addition of leather sawdust at the concentrations of 0, 5, 10, 15, 20, 25 and 30%. Discs of mycelium of P. ostreatus (BF24) and P. ostreatoroseus (POR01/06) were transferred to the center of plates containing previously prepared media. They were incubated at 28° C. In the second experiment rice straw substrate underwent the same experimental conditions described above. The substrate inoculated with the two strains was placed in test tubes and incubated at 28° C. The fungal biomass was evaluated by the difference between wet weight and dry weight, while for the mycelial growth, measurements were performed at predetermined times until the complete colonization of the medium or substrate. For P. ostreatus, it was found that the treatments with the addition of 5, 15 and 25% and 15% of this supplement led to a lower biomass and mycelial growth, respectively. In the mycelial growth phase the addition of 5% of this supplement to the rice straw had a positive effect on the development of P. ostreatus.