Effects of different carbon/nitrogen ratios on yield and bioconversion efficiency of Pleurotus ostreatus cultivated on cassava peels and sawdust-based substrate

Abstract

This study was aimed to evaluate the effects of different levels of wheat bran on the yield and bioconversion efficiency of Pleurotus ostreatus cultivated on an equal mixture of cassava peels and sawdust-based substrates. Two per cent lime was added to stabilise the pH of the substrate while different levels of wheat bran, namely C/N 17:0, C/N 17:1, C/N 17:3, C/N 17:6 and C/N 17:9 were added to enrich the substrate with nitrogen. Completely randomised design was used with three replications. Proximate analysis was conducted on the fruit bodies to determine the nutritional composition. Mushroom weight, mushroom number, stipe length, pileus diameter, dry weight of fruit bodies, dry matter loss, biological efficiency, bioconversion efficiency and number of mushroom flushes differed significantly with treatment. The nutritional composition of the fruit-bodies also differed significantly. C/N 17:0 was outstanding in supporting the colonisation, yield and bioconversion efficiency of P. ostreatus. Pleurotus ostreatus can be cultivated on an equal volume of sawdust (50%) and cassava peels (50%) without supplementing it with wheat bran or any nitrogen source. Higher C/N ratios hindered mycelial colonisation and fruit body formation. The lower the C/N ratio, the higher the nutrient composition of the mushroom fruit bodies.