ABSTRACT

Edible mushrooms such as Pleurotus Sajor -caju and Pleurotus ostreatus were grown on locally available agricultural wastes. The objective of the study is to determine the substrates (agricultural wastes), that is suitable for the cultivation of the mushrooms. The substrates used were rice straw, saw dust and vertiver grass, malt extract agar (MEA) medium was used for the laboratory medium by mixing lOg of' the malt extract broth powder and agar powdcr into 500 ml of water. This preparation was autoclaved at 1210 C (1 kg I cm 2 pressure) for 15 minutes and allowed to cool in an inoculation chamber to about 45 0 C and then lOmI of the medium was poured into sterile petri —dishes and allowed to gel. Then thoroughly washed cereal grains such as millet (Pennisetum sp.) guinea corn (sorghum sp.) was soaked for 24 hrs in water and then autoclaved. On cooling, pure cultures were inoculated into the grains and incubated at 27± 1 °C for about two weeks. Finally, dry vertiver grass, dry rice saw and saw dust were soaked in clean water overnight, after this, the substrates were pasteurized for 2 hours at a temperature of 800 C in a gas-heated drum. On cooling, 30g of the grain spawn were inoculated into the substrates. Fructification started about two weeks after inoculation, rice straw produced more number of fruitbodies of P. ostreatus, and P. sq/or caju than vertiver grass and saw —dust, but in terms of weight of fruitbodies, vertiver grass produced heavier weight of fruitbodies than rice straw and saw dust. Pleurotus species are best cultivated at a relative humidity of 85% and temperature between 29-31 °C. There should be proper aeration and flooding of the growing house for fructification to take place.