DETERMINATION OF THE EFFECT OF PH ON THE MYCELIUM GROWTH OF VOLVARIELLA VOLVACEA

ABSTRACT

Volvariella volvacea commonly known as Paddy straw mushroom, has become one of the most important cultivated mushrooms in the world due to its pleasant taste, distinct flavour, high content of protein, and short cultivation period of approximately two weeks. A comparative study was conducted to determine the effect of pH on the mycelium growth of Volvariella volvacea. For this purpose, the effect of pH on the mycelial extension of Volvariella volvacea., the cultural characteristics of the mycelium Volvariella volvacea under different pH conditions, the mycelia density rating of Volvariella volvacea on different pH values, and the mycelial biomass of Volvariella volvacea at different pH conditions were determined.The pure culture of the mushroom was obtained from African centre for Mushroom research and Development in Plant Biology and Biotechnology, University of Benin and was expanded on Potato Dextrose Agar (PDA). Thereafter, it was transferred to petri dish and kept at ambient condition until used. Different pH was used in preparing the culture media; they include pH 4.5, pH 5.0, pH 5.5, pH6.0, pH 6.5, pH7.0, pH 7.5.The result showed that the effects of pH on the mycelia growth of Volvoriella volvacea ranged from 4.5 - 7.5, with maximum mycelia yield observed between pH 5 and 7 while the highest mycelia growth rate was recorded at pH 7.0 (Neutral). Poor growth was recorded in the acidic pH region with mycelia growth (5.40mm) at 6. 0. Appreciable mycelia growth was recorded between the various pH treatments and there was significant difference within the groups. It also showed the effect of pH on the biomass of Volvoriella volvacea, were 5.5 pH concentrations had the highest biomass (0.82g), and pH 4.5 had the lowest biomass of (0.16 g).