Cultivation of the oyster mushroom (Pleurotus ostreatus) on cellulosic residues from rice straw

Abstract

The use of cellulosic residues and additives in Ghana to improve the biological efficiency (BE) and nutrient content of the oyster mushroom Pleurotus ostreatus strain EM-1 has been an area of continuous study in Ghana. The effect of varying substrate formulations of rice straw with rice husk and bran on the weekly mycelia growth rate, spawn run period, yield and biological efficiency (BE) of P. ostreatus strain EM-1 were studied. Based on the results obtained. Treatment A {Rice straw (97.5%) with rice husk (2%) and calcium carbonate (0.5%)} recorded the highest mean mycelial growth rate (10.15 cm) in the first week and also recorded the lowest mycelia growth rate (5.30 cm) in the third week. There were significant differences (P<0.05) in the mycelia growth rates for the 1st week among the treatments. All the treatments containing rice straw: ranging from 43.75% to 97.5% took 28 days to be fully colonised compared to the control which took 35 days. The suitability of the rice straw and rice husk treatments in descending order are combinations of rice straw (50%) and rice husk (50%); rice straw only (100%) and rice straw (87.5%) and rice husk (2%) and sawdust only, having biological efficiencies of 154.29, 124.91, 107.47 and 75.08 respectively with the rice straw and rice husk showing a 37% increase over the control. All the treatments showed significant differences in biological efficiencies at P≤0.05. Based on this increase in the BE of Pleurotus ostreatus strain EM-1, rice straw and rice husk at 1:1 ratio can be used as an alternate substrate for producing more mushrooms in rice growing areas