Effect of Supplements on Growth and Nutritional Content of Pleurotus pulmonarius Cultivated on Rice Straw

leurotus pulmonarius is one of the most preferred edible mushrooms being cultivated in the tropics and has gradually gained prominence in the subtropical and temperate zones of the world. Pleurotus spp are popular and widely cultivated throughout the world mostly in Asia, America and Europe because of their simple, low cost production technology and high biological efficiency (Mane et al., 2007). P. pulmonarius, commonly known as the Indian Oyster, Italian Oyster, Phoenix Mushroom, or the Lung Oyster, is a mushroom very similar to Pleurotus ostreatus , the pearl oyster, but with a few noticeable differences. The caps of pulmonarius are much paler and smaller than ostreatus and develop more of a stem. P. pulmonarius also prefers warmer weather than P. ostreatus. Otherwise, the taste and cultivation of the two species is generally described as largely the same (Stamet, 2000). In nature, P. pulmonarius is an active decomposer of wood and several other substrates. It has ability to colonise and digest several types of materials containing lignin, cellulose, starch, sugars and fermented proteins, due to its capacity of secreting a spectrum of enzymes. Mushrooms are increasingly being recognized as important food products for their significant role in human health, nutrition and disease. Several species of mushrooms are of great importance because of their medicinal properties, for example, they are active against hypercholesterolemic conditions, hypertension, diabetes, cancer and other infections (Alam et al., 2007). Several studies have shown that P. pulmonarius and its extracts have many possible medicinal applications for a wide range of conditions. Extracts of P. pulmonarius have proved effective against acute colitis in a mouse model, suggesting a possible clinical use in the treatment of colitis (Lavi et al., 2010). A further study by the same authors concluded that the extracts also inhibit colon cancer formation associated with colitis in mice (Lavi et al., 2011). Jose et al. (2002) reported that a methanol P ABSTRACT Mushrooms are increasingly being recognized as important food products for their significant role in human health, nutrition and disease. Various substrates have different effects on the growth, yield and quality of mushrooms. This study was carried out to investigate the effect of rice straw substrate supplemented with different additives on the growth, yield and nutritional content of Pleurotus pulmonarius. The additives used as supplement were maize waste, Brewery waste and soya bean waste. The results obtained indicated that the growth and yield of P. pulmonarius varied widely with the various additives used. After the first and second flush, Brewery waste gave the highest mean number of fruiting bodies (25.5) and highest mean fresh weight (54.1g). The least mean number of fruiting bodies (6.5) and lowest fresh weight (22.4g) was obtained from the substrate without any additive. Fruiting body with highest length of stipe and pileus diameter was obtained from those grown on substrate supplemented with soya bean waste. The additives had effect on the nutritional value also, as highest protein content (26.92%) was observed on rice straw supplemented with Brewery waste and soya bean waste respectively. The lowest moisture content (8.51%), ash content (5.22%) and crude fibre (2.31%) were obtained from rice straw without additives. In the present study, substrate supplementation improved growth, yield and quality of P. pulmonarius. Due to high protein content of P. pulmonarius, it can be used as a substitute for expensive meat and fish in developing nations like Nigeria. Original Research Article