Fungal isolation and spawn preparation
The fresh samples (2×2 mm) were isolated on 9 mm Petri plate containing DifcoTMPotato Dextrose Agar (PDA) media and observed until the mycelial colony covered the whole plate. Pure cultures of isolates were obtained from subculture preparation and spawn was prepared by using sterile wheat grains. The grains were washed, autoclaved at 121°C for 20 minutes and allowed to cool in 100 ml conical flask. The fungal mycelia were inoculated on the grains and the mouth of the flask was covered with aluminium foil and wrapped with parafilm to pr event contamination by insects, fungi and bacteria. The spawn was ready to use for polybag cultivation after the mycelia covered all the grains in the conical flask.