Fungal and Insect Pests of the Edible Mushroom Pleurotus ostreatus

Pleurotus ostreatus is an edible mushroom cultivated worldwide, with economic, nutritional and medicinal values, which requires a shorter growing period compared to other edible mushrooms. Fungal and insect pests of cultivated P. ostreatus were examined. Fungi from infected mother spawn of P. ostreatus were isolated, characterized and identified, while various insect pests on P. ostreatus were also collected and analysed. The plates showing micrographs, morphological and cultural characteristics of fungal isolates obtained were recorded. Fungi species isolated from infected mother spawn of P. ostreatus were identified as Aspergillus flavus, A. niger, Cladosporium sp., Penicillium oxalicum, Fusarium oxysporium and F . verticilliodes . The growth of Cladosporium sp. was slow on Potato Dextrose Agar (PDA) plates compared to Aspergillus sp. and Fusarium sp. which was very fast. Insect belonging to the orders Collembola, Diptera and Araneae were encountered on the cultivated P.ostreatus. These groups of insects were found at adult stage of life. Infestation by order Collembola (springtail) on P. ostreatus was found to be higher in incidence with percentage composition of 50.0%, followed by order Diptera (fruit flies) and order Araneae (spider) with 33.3% and 16.67% composition respectively. Distinguishing features of each pest and the features of damage done on mushroom were also observed and recorded.