Evaluation of Tea Wastes as an Alternative Substrate for Oyster Mushroom Cultivation
Oyster mushroom (Pleurotus sajor caju) is locally cultivated on sugarcane bagasse substrate. Due to decreasing supply of bagasse, there was an urgent need to identify alternative substrates. The aim of this study was to evaluate tea wastes as an alternative substrate for oyster mushroom cultivation. The first step was to assess growth of oyster mushroom mycelium on PDA containing tea wastes extract. Antifungal substances found in tea wastes slowed mycelial growth but was not lethal to it. As positive results were obtained, substrate mixtures containing different proportions of tea wastes and sugarcane bagasse were assessed in fruiting bags to identify the most promising substrate mixture on which the effects of supplements such as lime and crushed maize seeds were assessed independently. Substrate containing 75% sugarcane bagasse and 25% tea wastes showed promising results in terms of mycelial growth and fructification. This substrate mixture was selected for further trials with lime and crushed maize. Highest yield of mushroom was obtained with substrate mixture
supplemented with 5% lime whereas the substrate mixture gave the highest yield at 0% crushed maize. Results obtained showed that tea wastes can be successfully used to cultivate oyster mushroom but it need to be mixed with sugarcane bagasse for the source of cellulose. Substrate mixture containing 75% sugarcane bagasse and 25% tea wastes, supplemented with 5% lime, yielding about 200g of mushroom can be proposed to growers.
Keywords: Oyster, mushroom, substrate, alternative substrate, tea wastes.