Identification and morpho-molecular characterization of low spore strain in oyster mushroom

Sporocarps of oyster mushroom liberate enormous spores and cause allergic reactions to workers involved in its cultivation. These spore-related allergies include stiffness or pain in the forearms, limbs, itchy throat, grogginess, and respiratory problems and are major problems during oyster mushroom cultivation.

In this study, we have generated seven hybrids using single-spore isolates (SSIs) of Pleurotus ostreatus var. florida (DMRP-49) and P. ostreatus (DMRP-30). Chimera was observed during cultivation trial of these hybrids and led to the development of low spore-producing/sporeless strain (DMRP-395) as evident from spore print and microscopic analysis. Further, the cultivation trial of this sporeless strain revealed a bunchy fruiting pattern and required 20-24 °C temperature for fruiting. At par yield was observed in sporeless strain. Notably, a prominent infundibuliform-shaped pileus along with central attachment of stipe was observed in the sporeless strain. Moreover, genetic diversity and principal component biplot analysis revealed resemblance of sporeless strain with one of the parental strain, i.e., P. ostreatus var. florida (DMRP-49).

The developed sporeless strain (DMRP-395) contains high protein and at par yield as compared with the control (DMRP-136). This sporeless strain will be helpful to reduce spore-related allergic responses in mushroom growers.