Agronomic Qualitative Viability of Spent Pleurotus Substrate and its Mixture with Wheat Bran and a Commercial Supplement

Abstract

AbstractIn this study the agronomic viability of Pleurotus ostreatus (Jacq.) P. Kumm., is studied by reusing the spent substrates previously used in crops of the same mushrooms. After the physical and chemical characterization of the substrates, we have evaluated the qualitative production parameters in one growing season. As base material, the experiment was arranged with wheat straw (WS) and spent Pleurotus substrate (SPS) to generate prepared substrates, alone and mixed with different proportions of wheat bran (WB) and the commercial supplement Calprozime®. With the substrates supplemented with 300 g of WB + 120 g Calprozime®, we obtained generally higher ash (8.43%) and protein contents (24.75%) in the mushrooms. These substrates also achieved acceptable breaking strength values (Bs) (182.25 N) and compression energy (CE) (944.63 mJ) in the harvested mushrooms. In turn, these substrates promote lightness (60.31) and yellow‐blue (b*) (12.93) chromaticity of the harvested mushrooms. Consequently, these composts degraded by Pleurotus ostreatus formulations could be a low cost substrate, selective and balanced nutrient for the growth and development of the oyster mushrooms.Practical ApplicationsSubstrates supplemented with 300 g of wheat bran (WB) + 120 g Calprozime® could be integrated through new formulations and methodologies while lowering production costs and reducing the environmental impact of unusual waste. Spent Pleurotus substrate (SPS) is considered to be environmentally unfriendly, undesirable, and presents a solid waste disposal problem for mushroom growers. If SPS could be easily available at a low cost it could be integrated into new formulations and methodologies, diminish the environmental impact of the waste produced during mushroom cultivation, limit the grower's dependence on straw, and decrease the environmental impact of its overgrowing accumulation.