Establishment of in vitro culture initiation for mutation induction in Volvariella volvacea

Volvariella volvacea is an edible mushroom contributes to nutritional, pharmaceutical and cosmeceutical values. Thus, development of new mushroom strains is needed to sustain the industries. However, natural selection of V. volvacea mushroom is hampered by a narrow genetic background of the species in selecting better quality strains. Alternative ways in doing selection to create variants among the strains is through mutation induction by using a physical mutagen via gamma radiation. The technique can be done by exposing in vitro culture of the mycelium grown on semi solid Potato Dextrose Agar media (PDA) to acute gamma radiation. A series of doses were used for acute gamma irradiation ranged from 0 Gy, 0.1 kGy, 0.2 kGy, 0.3 kGy, 0.4 kGy, 0.5 kGy, 0.6 kGy, 0.7 kGy, 0.8k Gy, 0.9 kGy, 1.0 kGy, 1.5 Gy, 2.0 kGy, 3.0 kGy and 4.0 kGy at dose rate 0.013 kGy/ min. Previously, samples used for the irradiation was initiated and propagated up to 3rd subculture prior to irradiation. Growth performance of the mycelium was recorded at two days interval for eight days. Qualitatively, mycelium was observed and LD₅₀ was established. LD₅₀ for V. volvacea was determined at 1.86 kGy. This paper described the in vitro culture initiation for mutation induction process and the establishment of LD₅₀ for V. volvacea. Findings for this study are important for nuclear technology application related to mutation induction in sustaining new improved V. volvacea strains. (author)