Abstract

A total of eight locally available substrates and substrate combinations were tested for their productivity and biological efficiency (BE) for cultivation of commercial mushroom strain (Pleurotus ostreatus). Spawn preparation and running were carried out following standard methods. Main substrates were steam sterilized for 1 h and were inoculated with 10% spawn. The inoculated main substrates were arranged in a completely randomized design on shelves in the mushroom growing room and incubated at ambient temperature (22 ± 2°C). Relative humidity of the mushroom growing room was controlled by manually spraying water on the walls and placing open containers filled with water in the corners of the room. Data were analyzed using SPSS version 14. The substrate types had significant (p < 0.05) effects on the rate of mycelial extension, mean incubation period and yield at 2^nd and 4^th flushes, number of matured fruit bodies, aborted pinheads, weight of matured fruit bodies and BE. The fastest mean value (0.69 cm/day) of mycelial extension was recorded from sdZcCh (combination of sawdust of Cordia africana and Pouteria adolfi-friederici, corncobs and coffee bean husks). However, mycelial growth in coffee bean husks was completely ceased after 15 days. The first pinning took 29 ± 2.3 days followed by 12 ± 6.3, 7.6 ± 2.3, and 6.4 ± 2.5 between the 2^nd, 3^rd and 4^th flushes, respectively. Mean durations from pinning to maturation ranged from 3 to 5 days. The highest BE was obtained from sdZcCh (77.38%). The present findings indicate the potential of agricultural wastes for cultivation of oyster mushrooms. All the substrates that gave over 40% BE could be recommended for oyster mushrooms cultivation.

Key words: Biological efficiency, edible mushrooms, Pleurotus ostreatus, spawn.