ABSTRACT

This study was conducted to determine the influence of different straw substrates on the productivity, macro-morphological characters and mycochemical properties of Pleurotus ostreatus fruit bodies. 1kg dry weight each of Andropogon gayanus, Sugarcane bagasse, maize, Pennisetum purpureum and Panicum maximum straws were chopped into 2-3cm long and made into 5 replications of 200g each. 30g grain based spawn of P. ostreatus was used to inoculate each replicate substrate stuffed into 2.5liter transparent plastic bucket. Experiment was conducted in a completely randomized design (CRD). Data were analyzed using statistical package for social scientists (SPSS) version 22.0, means were separated using Duncan multiple rang test (DMRT) at 5% level of significance. Results revealed that A. gayanus straws produced fruit bodies with the highest number (155) of fruit bodies after 14 days of inoculation contrary to S. bagasse at17 days with highest mean cap diameter of 6.01± 0.80cm. Fruit bodies from A. gayanus had the highest mean weight (4.75±0.29), yield (777.76g) and biological efficiency of 77.78% while those of maize straws had the least (4.896.06±42%) mean cap diameter. Moisture content (20.226.06±0.42%) and Crude protein (23.61±0.19 significantly p≥0.05 high in fruit bodies from A. gayanus contrary to those of P. maximum (7.00±0.00) and P. purpureum (9.38±0.03) respectively while ash (5.08±0.0%) and ether extract(3.92±0.00%) were highest in fruit bodies obtained from maize straws. Vitamins B1, B2, B3 and E contents were relatively low in fruit bodies produced by all the substrates except P. maximum (21.13±0.01) and maize straws (12.78±0.02) which the highest concentrations of vitamins C and A respectively. Fruit bodies harvested from A. gayanus had the highest (21.48±0.32) calcium content similar to maize straws with the highest K(46.26±0.07), Na(14.84±0.06), Mg(30.47±0.75) and Fe (3.17±0.01) concentrations. A. gayanus substrate was observed with the highest number of fruit bodies, yield and biological efficiency and should be adopted in the commercial production of P. ostreatus while maize straws should be used when mineral nutrients rich fruit bodies are desired.