ABSTRACT

This work involved the investigation of the effect of different substrates (Andropogon gayanus, Pennisetum purpureum and Panicum maximum) on the yield, proximate composition and mineral composition of Pleurotus ostrealus var florida. The highest gross yield fruit-bodies was obtained from the substrate Andropogon gayanus (1059.84%), followed by Panicum maximum (568.4%), while the least was found in Pennisetum purpureum (202%). Similarly the fruit-bodies of substrates Andropogon gayanus weighed more than those from other substrates for both fresh and dry weight. Based on the proximate composition, carbohydrate was found to be highest (72.0311.52) in mushrooms harvested from P. purpureum^ followed by P. maximum (71.3910.83) while fruit bodies harvested from A. gayanus gave the lowest (70.6911.72). Ether extract in all the fruit bodies was the lowest among all the parameters studied at (0.3810.03) in P. purpureum (0.3010.02) in A. gayanus and (0.2010.02) in P. maximum. Based on the mineral composition, Result showed that all the fruit-bodies obtained from A. gayanus substrate contained appreciable amount of Calcium (1.6010.20), Potassium (2.3510.05), Magnesium (31.2610.035) and Sodium (2.2010.20). Similarly, fruit bodies obtained from P. maximum had the highest (75.7410.035) concentration of Phosphorus while there was no significant difference in the amount of sulphur contained in fruit-bodies harvested in all the substrates at p<0.05. However, the lowest (0.7010.10) Calcium composition was recorded in mushrooms harvested from P. purpureum. Likewise P. maximum gave the lowest Sodium (1.7010.10) and free Nitrogen (1.9010.10) contents. The result ofthe investigations was discussed in line with the best substrates for the maximum production of Pleurotus osreatus fruit-bodies with better qualities. The investigation concluded that growing Pleurotus ostrealus on A. gayanus straw produced the highest fruit-bodies among other substrates which will aid in the wide production of mushroom for market values. Generally, Pleurotus ostrealus contain valuable nutritional properties.