Changes in chemical composition and in sacco degradability of wheat straw treated with Pleurotus sajorcaju and P. ostreatus.

摘要

Two strains of white rot fungi, P. sajor-caju and P. ostreatus, were grown on moist wheat straw to study their efficiency in degrading lignin and ability to cause an increase in the in sacco degradability of wheat straw. Fungi were grown on wheat straw andanalysed after incubation periods of 0, 5, 10, 15, 20, 30 and 40 days at 80% moisture at 25deg C. The nylon bag method (using a buffalo) was used to assess rumen degradability of the samples. DM loss increased (P<0.01) as the incubation period increased for both types of fungi. The degradation of NDF, ADF, cellulose and hemicellulose was similar in straw treated with both fungi, but P. ostreatus showed better lignin degradation than P. sajor-caju (72.88 vs. 62.85% of the initial amount present in the substrate). The concentration of total soluble phenolics in treated straw remained constant during the first 10 days of treatment with both fungi. 40 days of incubation with P. ostreatus caused a greater increase in in sacco DM degradability of wheat straw compared with P. sajor-caju.