摘　要：本试验利用电子束及γ射线两种射线对渐狭蜡蚧菌（Lecanicillium attenuatum）3166进行诱变处理，研究适于渐狭蜡蚧菌诱变选育的吸收剂量以及诱变菌株生物学特性。结果表明：电子束及γ射线诱变渐狭蜡蚧菌的最适剂量均为200 Gy，渐狭蜡蚧菌的电子束辐射敏感性D10值为191 Gy、γ射线D10值为366 Gy；以产孢速率为指标筛选获得突变菌株8株，其中5株的菌丝生长及产孢速率较出发菌株显著提高，均为电子束诱变所得，产孢速率分别较出发菌株提高了30.45%、31.55%、23.66%、64.83%、68.77%；诱变菌株的胞外几丁质酶比活在培养5 d时达到峰值，诱变株Ⅱ111、Ⅱ164、Ⅱ181的几丁质酶比活分别较出发菌株显著提高29.29%、54.45%、19.18%，其中Ⅱ164酶比活可达1 707.41 U/mg prot；胞外蛋白酶比活在培养7 d时达到峰值，Ⅱ111、Ⅱ164、Ⅱ181的蛋白酶比活分别较出发菌株显著提高17.98%、13.17%、16.50%，其中Ⅱ111酶比活达到30.71 U/mg prot，且渐狭蜡蚧菌诱变株生长速率与胞外酶比活有强相关性。本研究为渐狭蜡蚧菌后续的害虫防治及开发利用提供了理论基础。
关键词：渐狭蜡蚧菌；辐射诱变；突变菌株；生物学特性；胞外酶比活
中图分类号：TL99；S476.1                  文献标志码：A              DOI：10.3969/j.issn.1007-7146.2023.05.006

Abstact: In this study, electron beam and γ-ray were used to mutagenize Lecanicillium attenuatum 3166, and the absorbed dose suitable for mutation breeding of Lecanicillium attenuatum and the biological characteristics of the mutagenized strain were studied. The results showed that the optimal dose for electron beam and γ-ray mutagenesis of Lecanicillium attenuatum was 200 Gy, the electron beam D10 value of Lecanicillium attenuatum was 191 Gy, and the γ-ray D10 value was 366 Gy; eight mutant strains were screened and obtained with spore production rate as the index. Among them, the hypha growth and spore production rate of five strains significantly increased compared with the parent strain, which were all obtained by electron beam mutagenesis. The spore production rate increased by 30.45%, 31.55%, 23.66%, 64.83% and 68.77% respectively compared with the parent strain. The extracellular chitinase activity of the mutant strain reached the peak after five days of culture, and the chitinase activities of mutant strains Ⅱ111, Ⅱ164 and Ⅱ181 increased by 29.29%, 54.45% and 19.18% respectively, compared with that of the parent strain. The chitinase activity of mutant strain Ⅱ164 reached 1 707.41 U/mg prot; the extracellular protease activity reached its peak after 7-day culture, and the protease activities of Ⅱ111, Ⅱ164 and Ⅱ181 were significantly increased by 17.98%, 13.17% and 16.50% respectively as compared with those of the parent strain, wherein the enzyme activity of Ⅱ111 could reach 30.71 U/mg prot, and the growth rate of the mutant strain had a strong correlation with the extracellular enzyme activity. This study provides a theoretical basis for the follow-up pest control, development and utilization of Lecanicillium attenuatum.
Key words: Lecanicillium attenuatum; radiation mutagenesis; mutagenized strain; biological property; extracellular enzyme specific activity
（Acta Laser Biology Sinica, 2023, 32(5): 431-440）