Conversion of spent mushroom compost to a solid substrate for mass production of an entomopathogenic fungus, Isaria fumosorosea (Wize)

Spent mushroom compost (SMC), an organic waste produced from mushroom production farms it is a complex waste management issue in many developing countries and developed countries. In this study, an effort to convert the waste into a beneficial use was carried out. Composts from varying stages of fermentations in a mushroom production line were chemically analysed and tested for their suitability for mass production of an entomopathogenic fungus, Isaria fumosorosea (Wize). The result shows that the compost taken from early fermentation stages did not support the growth of I. fumosorosea, the fungus, however, grew well thereafter on substrates from the mushroom harvesting stage and SMC. The conidia from the SMC not only remained as pathogenic as conidia from rice to its target pest, Bemisia tabaci but they were also more resistant to UV–B radiation and have a longer shelf life than conidia from rice. These properties indicated that SMC can be used as a solid substrate for mass production of the entomopathogenic fungus, I. fumosorosea for an environmentally friendly fungal–based biopesticide.