Abstract:
Oyster mushrooms are lignocellulolytic fungus belonging to the genus Pleurotus, widely distributed in temperate and tropical regions which have been used as food and medicinal purpose. This research was carried out to evaluate the yield, biological efficiency and nutritional qualities of P. ostreatus M2191 and P.sajor-caju M2145 grown on different agroindustrial wastes in Debre Berhan, Ethiopia. Brewery spent grain, wheat straw, cotton seed, saw dust; bean straw and teff straw were used as the main substrates at different compositions. Wheat bran (8%) and gypsum (2%) were used as additives of the main substrates. The cultivation of Pleurotus species was performed under aseptic conditions and growth and development was evaluated daily. The highest mean yield and biological efficiency were 856 g, 99.55% and 840g, 97.7% for P.ostreatus M2191 and P. sajor-caju M2145 respectively on 25% brewery spent grain and 75% cotton seed. P.ostreatus M2191 resulted lowest yield (517.5g) and biological efficiency (60.15%) on 100% saw dust whereas P.sajorcaju M2145 had provided lowest yield (505g) and biological efficiency (58.7%) on 75% brewery spent grain and 25% saw dust. The maximum protein (39.43%) for P.ostreatus M2191and (38.14%) for P. sajor-caju M2145 were obtained from 25% brewery spent grain and 75% cotton seed. Saw dust (50%) and 50% brewery spent grain resulted minimum (24.8%) protein content of P.ostreatus M2191 whereas for P.sajor-caju M2145 from 75% brewery spent grain and 25% saw dust. The highest fiber (12.87%) for P. ostreatus M2191 and (13.46%) for P. sajor-caju M2145 was gained from 25% wheat straw +75% brewery spent grain and the least (6.6%) for P. ostreatus M2191 from 75% brewery spent grain+25% cotton seed and (5.89%) for P. sajor-caju M2145 from 25% brewery spent grain+75% cotton seed respectively. The brewery spent grain and agricultural residues could be used to grow P.ostreatus M2191 and P.sajor-caju M2145 at Debre Berhan weather conditions.