鸡骨草根瘤菌的分离及其生物学特性研究

目的:研究鸡骨草根瘤菌的生物学特性。方法:将来自不同生态环境的鸡骨草根瘤经分离纯化获得根瘤菌菌株,再进行生长特性、增代时间以及对温度,pH,NaCl和抗生素的耐受性试验。结果:原产亚热带的鸡骨草根瘤菌在YMA培养基上代谢产碱,平均增代时间为14.8h,应属慢生型根瘤菌;来源不同生态环境的参试菌株在对高温的忍耐能力、酸性环境的适应性、抗生素的敏感性等多种抗逆特性方面存在较大的差异,但对碳源和氮源的利用特性比较一致;接种根瘤菌70d后,鸡骨草幼苗的结瘤率为85.0%,茎叶干物质增加51.1%。结论:鸡骨草根瘤菌存在较为丰富的根瘤菌抗高温和抗酸性环境的种质资源,为今后在生产上利用鸡骨草根瘤菌资源,提高原料药材的质量具有重要的意义。

Isolation and biological characteristics of rhizobia strains from Abrus cantoniensis

Objective: The research aimed at studying the biological characteristics of rhizobia isolated from Abrus cantoniensis. Method: The rhizobia strains, isolated from different environments in Guangxi, were studied for their growing characters and the generation time. They were also compared for survival capabilities under stresses caused by NaCl, pH, temperature, and different kinds and concentration of antibiotics. Result: The strains obtained from A. cantoniensis in subtropical zone produced alkali in YMA medium, the average generation time was 14.8 hours, and thus they belong to slow-growing rhizobia. Rhizobia strains differed greatly in respect to tolerance of high mperature , adaptability of acidic environment and sensitivity to four antibiotics, but they had the same abilities of using different carbon and nitrogen sources. After 70 days from inoculated strains, the seedling formed nodules on the root(85.0% ) , and the dry matter of vine was increased by 51.1 % . Conclusion: The rhizobia strains isolated from different ecological environments are good germplasm resources of tolerances to high temperature and acidic environment. The research will greatly help utilize the rhizobia resources and enhance the quality of crude drugs of medicinal leguminosae.