Growth and Cultivation Studies of Pleurotus tuberregium (Fr. Singer) on Sawdust of Brachystegia nigerica Supplemented with Cassava Starch and Bambara Groundnut

The effect of cassava starch and bambara groundnut powder on the growth of Pleurotus tuberregium (Fr. Singer) was investigated. The growth of Pleurotus tuberregium on sawdust of Brachystegia nigerica was supplemented with starch and bambara groundnut (Vigna subterranean) at 0%, 5%, 10%, 15% and 20% concentrations respectively. Mycelia extension, mycelia growth morphology and biomass were influenced significantly at p > 0.05 by these supplements. Starch supplemented medium had a faster growth rate (80.66 ±0.66 mm/day) at 5% but bambara groundnut-supplemented medium had its highest rate (78.33±1.67mm/day) at 10%. Bambara groundnut supplemented medium had the highest biomass (386.00±66.00 mg) at 10% and least biomass (188.00 ±3.00 mg) at 15%, while cassava starch supplemented media had its highest biomass (203.00±28.00 mg) at 5% and least (133±12.00 mg) at 15%. Half (50%) colonization was achieved after 11 days of colonization for 10% starch and it took 30 days to attain full (100%) colonization for 10% starch level. Accumulation of exudates suspected to be exopolysaccharide was observed as the mycelium grows in the substrate bags supplemented with starch. Lower concentration of local starch supplement supported a higher production of the exopolysaccharide. Cassava starch can be used to induce the production of exudates of P. tuberregium.