Successful outdoor cultivation of a photosensitive wild strain of edible Pleurotus ostreatus (Fr.) Kummel (Oyster mushroom) from the Western Ghats region of Goa

Abstract

There is considerable interest in identifying wild tropical strains of oyster mushrooms useful for cultivation, strain improvement and systematic breeding programme. During routine surveys to identify such strains from Goa's western ghats an interesting wild form of Pleurotus ostreatus was found growing on logs of wild Mangiferra indica L. a novel habitat for the species reported for the first time. After obtaining and screening several pure isolates, a fertile strain BA-50/GUOMS was selected for cultivation under natural outdoor conditions. Spawn prepared on wheat grains was produced within 11 days and was used to ramify sterilized paddy straw as substrate using standard polybag technique. Spawn run was initially slow and took 52 days. Mushrooms fruitbodies identical to the original wild type were produced in eight flushes at intervals of 8 to 13 days for each flush over a period of four months. These had pleasant odour, better shelf life, tougher texture, resistance to insects, fungi and bacteria, exhibited photosensitivity by producing brownish pigment in direct sunlight and responded well to outdoor conditions for fruit body initiation with ambient temperature ranging from 23-35 degrees C.