Dose-effect relationship of edible fungi with low-energy heavy-ion implantation

Abstract

To reveal the dose-effect relationship of edible fungi via low-energy heavy-ion implantation, the conidia of three species of edible fungi were irradiated with 15 keV nitrogen ions at different dosages (0, 2, 4, 6, 8, 10, 12, and 14)×1015 cm-2. The effects of heavy ions on the etching, survival rate, and growth of mycelium in a plate culture and the biomass and polysaccharide content of mycelium in shake flask fermentation were studied. The results showed that low-energy heavy-ion implantation could evidently etch the conidia of edible fungi, and the survival rate curve showed a “saddle-shaped” dose effect as the implantation dose increased. Compared with those without ion implantation, the growth rate and density of mycelium in the plate culture were significantly different at each dose, and the diameter of the colony was more than 8.20 cm at the peak dose of the survival rate curve. There was a delayed effect of mycelium aging—particularly, there was no crust—on the 7th day of the plate culture at the peak dose of the survival rate curve. The biomass and polysaccharide content of mycelium in flask fermentation were different at each dose. The polysaccharide content of mycelium was generally high, and the biomass of mycelium reached a maximum at the peak dose of the survival rate curve, which was more than 15.30 g∙L-1 . This study provides an experimental basis and a methodological reference for the low-energy heavy-ion mutation breeding of edible fungi.

Keywords

• low-energy heavy ions
• edible fungi
• conidium
• dose-effect relationship