Abstract

• This research deals with the study on the effect of gamma irradiation on yield and quality of oyster mushroom in each generation. The spawn of mushrooms sample (Ngwe-Hnin-Mho) was collected from Kaung-Ei Mushroom Nursery, South-Okkalapa Township,Yangon Region. The sample of mushrooms was treated with different doses (0.25, 0.5, 0.75 and 1 kGy) of gamma radiation. After irradiation, these spawn were successively cultivated to third generation. The yield and some agronomical characteristics of different generations were determined. To be safe for consumption, the induced activity of each mutant sample (OMG 0.25, OMG 0.5, OMG 0.75, OMG 1) was monitored by using NaI(Tl) Scintillation Gamma Counter at Nuclear Laboratory, Department of Chemistry. It was found that there were no induced activity in these samples. Thus, they are safe for human consumption. Agronomical characteristics such as average diameter of mushroom, yields, fruiting period, shelf-life of mutants oyster mushrooms were determined. And then, study of SEM and FT IR measurement was done. All doses of irradiation provide the higher yield of mushroom than those of control for every generation. The shelf-life of each mutant oyster mushroom increase than that of control. It was found that the fruiting periods of OMG 0.75 and OMG 1 always provided 1 day to 5 day shorter fruiting period than that of others. Thus, it is to reduce the time of producing oyster mushroom. The study of SEM was done for morphology of irradiated oyster mushroom. From this study, one evident fact is that there is no similar pattern between non-irradiated and irradiated oyster mushroom in all generation. From the FT IR spectra, it was found that effect of gamma irradiation did not vary the functional groups in the oyster mushroom up to third generation.