Pleurotus Tuber-Regium from Nigeria

Abstract

SUMMARY Studies have been carried out on Pleurotus tuber-regium, a tropical sclerotial basidiomycete obtained in Nigeria. Both the sclerotium and the fruit bodies are edible. The economic importance to the Nigerian people, particularly in traditional medicine, is discussed. When kept in a warm, humid atmosphere, the sclerotium readily produced fruit bodies which matured within seven da. Minimum temperature for mycelial growth was around 15, optimum 35, and maximum around 40 C. The fungus utilized as carbon sources a number of carbohydrates including fructose, mannose, xylose, glucose, cellobiose, maltose, dextrin, starch, cellulose, mannitol and sorbitol. Pleurotus tuber-regium (Fr.) Sing. is a basidiomycete found in the tropical and subtropical regions of the world (Singer, 1961; Zoberi, 1972, 1973). It forms a large, spherical to ovoid, subterranean sclerotium, composed of fungus tissue, sometimes up to 30 cm or more diam. The sclerotium is dark brown on the outside and white inside. Pleurotus tuber-regium initially infects dry wood where it produces the sclerotium which may become buried in the soil. The fungus is common in Nigeria where farmers usually lift the sclerotium out of the soil or wood while cultivating their farm. If the sclerotium is kept in a warm, humid place, it continues to produce fruit bodies one after the other over a period of time whose length depends on the size of the sclerotium. The fungus is consumed popularly in Nigeria and attempts are now being made to determine whether fruit bodies could be produced on a large scale. Nigeria is a country of many tribes, the Hausa in the North, Yoruba in the West, Urhobo in the Mid-West, and the Ibo in the East, to mention a few. Each tribe has recognized mushrooms for many years, and the people have made use of a number of these economically in their daily life. As part of this study, people from different parts of Nigeria were interviewed to determine their knowledge of P. tuber-regium. Prior to the present work, no physiological study has been reported