Base Substrate Sorghum Supplied with Nitrogen Additive Enhanced the Proliferation of Oyster (Pleurotus ostreatus (Jacq.: Fr.) Kummer) Mushroom Spawn Mycelium

The experiment was conducted to evaluate the performance of Pleurotus ostreatus (Jacq. Fr. ) Kummer mycelium on spawn media prepared from base substrate sorghum supplemented with combination of additives namely wheat bran, CaCO3, CaSO4, urea, sucrose and citric acid. Five spawn substrate combinations in 3 replications had been tested and data on fresh mycelial weight change 5, 10, 15, and 20 days after inoculation (DAI) and percentage mycelium coverage (PMC) at 20 DAI were collected. Completely randomized design was employed and the data was analyzed using SAS version 9.0. The result indicated differences in mycelial fresh weight (p less than 0.05) after inoculation with the highest substrate weight reduction recorded at 20 DAI. Consequently, spawn substrate media combined from sorghum, wheat bran, CaCO3, CaSO4, and urea was found to be the most favorable media mix while 20 DAI was incubation period for better mycelial growth. Similarly, the qualitative data was found to be in support of the above result and there was significant difference in PMC at 20 DAI. Therefore, this study indicated substrate media combined from sorghum (87.2 %), wheat bran (10 %), CaCO3 (1.5 %), CaSO4 (0.5 %), and urea (0.8 %) as the best alternative media for the production of P. ostreatus mushroom spawn.