The oyster mushroom Pleurotus ostreatus is the third important edible
mushroom in the world, following the button and shiitake mushrooms.
There is an increasing interest to utilize mutation in order to obtain desirable
characteristics in edible mushrooms, including P. ostreatus. However, there
is a scientific shortage of information available on accurate experimental
details of mutation induction in P. ostreatus, particularly while it comes to
basidiospores. Therefore, the objective of this study was to obtain a reliable
method to induce physical and chemical mutations in P. ostreatus var.
florida basidiospores through ultraviolet (UV) irradiation and ethyl methane
sulphonate (EMS). The findings revealed that the UV exposure at a distance
of 45 cm for 120 seconds and the EMS treatment at 1.5% caused a maximum
killing effect (over 95%) in the basidiospores, as compared to the untreated
spores. Moreover, the 50% lethality dose (LD50) was seen to be at 41.73±2.5
seconds of the U.V exposure and the concentration 0.51±0.05 % (v/v) of
EMS. The findings of this study warrant further research to investigate
morphological and developmental characteristics in fruiting bodies generated
by the putative mutant spores. In addition, the experimental conditions
established in this study may be useful for inducing mutation through UV
radiation or EMS treatment in basidiospores of P. ostreatus.