链霉菌BM10菌株的诱变选育

Mutation breeding of Streptomyces BM10 strain

链霉菌BM10菌株是中国热带农业科学院热带生物技术研究所从海南原始森林土壤中分离得到的一株生防菌,其代谢产生的抗菌物质对多种植物病原真菌具有较强抑制作用。以此菌株为出发菌株,进行紫外(UV)、微波(MW)、亚硝基胍(NTG)、硫酸二乙酯(DES)和氯化锂(LiCl)诱变处理,采用平板对峙初筛和摇瓶培养复筛,均能筛选到拮抗活性明显提高的突变菌株,尤以亚硝基胍诱变效果最好,其次是紫外线诱变、硫酸二乙酯诱变、氯化锂诱变和微波诱变。经传代实验,高效突变株N1-45-9对香蕉枯萎镰刀菌的拮抗效果比原始菌株提高69.4%,且遗传稳定性良好。

Streptomyces BM10 strain, a bio-control agent was selected from virgin forest soil in Hainan by Tropical Biotechnology Research Institute, Chinese Academy of Tropical Agricultural Sciences, and the metabolic antibiont produced by BM10 strain had strong inhibitory effect on many kinds of plant pathogenic fungi. Using BM10 strain as original strain for treatment with ultraviolet （UV）, microwave （MW）, nitrosoguanidine （NTG）, diethyl sulfate （DES） and LiCl for mutation, the mutation strains with higher antagonistic activity were obtained by prescreening of plate culture and second screening of shake flask culture, and the best mutational effect was obtained with nitrosoguanidine treatment, followed by the treatments of ultraviolet, diethyl sulfate, LiCl and microwave respectively. After passage culture experiment, the inhibitory effect of N1-45-9 on Fusarium oxysporum f. sp. cubense increased by 69, 4% as compared with the original strain, and showed steady heredity.