Effects of different substrates on the morphological characteristics and proximate content of Pleurotus pulminarius

Morphological characteristics and proximate content of Pleurotus pulminarius cultivated on different substrates were investigated. The substrates used are cotton waste, sawdust, palm fruit waste, paper, mixture of sawdust and palm fruit waste and mixture of cotton waste and paper (1:1) were sterilized and inoculated with Pleurotus pulminarius spawn (sorghum-produced) aseptically, incubated under controlled temperature and humidity before exposure to sunlight. Length and, diameter of stalk and pileus were measured during stages of harvest. Protein, fat, carbohydrate, crude fibre, ash and moisture content were determined by standard methods. Pleurotus pulminarius appeared on saw dust and cotton waste; paper, combination of saw dust and palm fruit waste, mixture of paper and cotton waste; and palm fruit waste after 2 days, 3 days and 5 days respectively. For the first stage of harvest, Saw dust had the highest length of stalk (cm) of 5.40 ± 0.63 and the lowest value of 2.70 ± 0.14 was obtained from palm fruit waste only. Mixture of paper waste and cotton waste has the highest diameter of stalk (3.25 ± 0.61 cm) (second harvest), the lowest diameter of stalk (0.4 ± 0.1 cm) was recorded for palm fruit (third harvest). Cotton waste had the highest diameter of pileus (7.88 ± 1.29 cm) (first harvest) while the lowest value (1.78 ± 0.63 cm) was obtained from mushroom harvested on the mixture of paper and cotton waste (second harvest). Pleurotus pulminarius harvested on mixture of paper and cotton waste has the highest percentage protein of 40.54% while the least value 28.79% protein was obtained from mushroom harvested on saw dust. Mushroom harvested on saw dust has the highest percentage fat content of 0.99% and palm fruit waste gave the lowest percentage fat of 0.74%. Palm fruit waste displayed the highest percentage ash and crude fibre contents of 4.38% and 4.81% respectively while cotton and paper wastes had the least ash and crude fibre content of 1.81% and 0.47% respectively. Saw dust gave the highest percentage carbohydrate of 62.54%s. Moisture content of 0.51% was obtained for mushrooms harvested on Palm fruit waste, Sawdust and mixture of sawdust and palm fruit waste as the least value while the mixture of paper and cotton waste has the highest moisture content of 3.49%. The study concluded that mushroom can serve as cheap source of food supplements such as protein, crude fibre, ash (micro and macro nutrients), fat, carbohydrate and moisture with beneficial bioconversion of agricultural and other wastes materials in the environment. Key words: Pleurotus pulminarius, cotton, sawdust, palm fruit, paper, wast