低能重离子注入食用菌的剂量效应关系

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

为了揭示低能重离子注入食用菌的剂量效应关系,采用15 keV不同注量(0、2、4、6、8、10、12、14)×10^(15)cm^(−2)的低能氮离子对3种食用菌的分生孢子进行辐照处理,研究不同剂量重离子对食用菌的刻蚀作用、存活率、平板培养菌丝体长势、摇瓶发酵菌丝体生物量及多糖含量的影响。结果表明,低能重离子注入对食用菌分生孢子刻蚀作用明显,随着注入剂量的增加其存活率均呈现先骤减后缓慢增加再陡减的“马鞍型”剂量-效应曲线;与未经离子注入相比,各剂量下平板培养菌丝体长速和密度差异显著,存活率峰值剂量下的菌落直径均超过8.20 cm,并伴有一定程度的菌丝体老化延迟效应,特别是存活率峰值剂量下,平板培养第7天的菌丝体基本都未出现结皮;各剂量下摇瓶发酵菌丝体生物量及多糖含量各不相同,存活率峰值剂量下菌丝体多糖含量普遍较高,菌丝体生物量达到最大均超过15.30 g∙L^(−1)。本研究可为食用菌的低能重离子诱变育种提供一定的实验依据和方法学参考。

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)×10^(15) 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.