EFFECT OF DIFFERENT AMOUNTS AND COMBINATIONS OF SUBSTRATES ON YIELD AND CONTAMINATION OF SPAWN PACKET IN OYSTER MUSHROOM CULTIVATION (Pleurotus ostreatus)

Abstract

The experiment was conducted during the period from November 2020 to March 2021 to study the effect of different amounts and combinations of substrates on the productivity, contamination and cost benefit ratio of oyster mushroom (Pleurotus ostreatus). The experiment was conducted with fifteen (15) different type treatments which were controlled amount of waste paper alone and combinations of waste paper and sawdust with three replications to achieve the desire objectives. The experiment was laid out in single factor Completely Randomized Design (CRD).Highest mycelium running rate (0.97 cm/day) was recorded in T 2 =500 g waste paper. The lowest harvesting period (39.33 days) was recorded in T 1 =250 g waste paper and T 2 =500g waste paper. Maximum average number of primordia and fruiting body per packet (59.33) was observed from T 10 =1500 g(75%Waste paper + 25% Sawdust) but the highest number of effective fruiting body per packet (18.67) was recorded from T 15 =1500g (25% Waste paper + 75% Sawdust). T 15 =1500g (25% Waste paper + 75% Sawdust) provided with the highest biological yield (165.33 g), economic yield (162 g), dry yield (11.44 g) and net returns (34.6 TK) but the highest of biological efficiency (44.93%) was observed when 75% of waste paper was added to 25% of sawdust to prepare 250g substrate. Trichoderma sp., Penecillium sp., Rhizopus stolonifer and Aspergillus niger were isolated and identified from contaminated substrates. Contamination severity was highest in T 15 =1500g (25%Waste paper + 75%Sawdust) and it increased with the increase of days after incubation. Among all the treatments, T 15 =1500 g (25%Waste paper + 75%Sawdust) was better economically as well as showed the best yield performance for the cultivation of oyster mushroom.