摘要
应用表型数值分类和16S rDNA PCR-RFLP分析方法,对分离自宁夏和内蒙古部分地区的沙冬青根瘤菌进行表型和遗传多样性研究.通过分离纯化获得44株供试根瘤菌,选取37株未知菌和11株参比菌株进行唯一碳氮源利用、抗生素和染料抗性、耐盐性、初始pH生长、生长温度范围和脲酶共94项生理生化性状测定,以及16S rDNA基因扩增和扩增产物的限制性酶切分析.结果表明,沙冬青根瘤菌在碳源利用、抗生素敏感性和染料抗性方面存在差异;对15项所选氨基酸氮源均能利用,无明显差异;具有较强的耐盐碱和耐高温能力.经过数值分类和16S rDNA PCR-RFLP比较分析,测试菌株具有丰富的表型和遗传多样性.测试菌株和参比菌株在80%的相似水平上产生2个表观群,表观群I和表观群II在鉴别特征上存在差异.数值分类中聚群的根瘤菌菌株在16S rDNA PCR-RFLP分析中也聚群,2种分析方法有基本的一致性.
Phenotypic and genetic diversities of rhizobia isolated from Amrnopiptanthus mongolicus growing in parts area of Ningxia and Inner Mongolia were analyzed with the methods of numerical taxonomy and 16S rDNA PCR-RFLP. 44 rhizobium strains were obtained through isolation and purification from root nodules, in which 37 unidentified tested strains and 11 reference strains were selected for 94 physiological and biological testing items such as utilization of sole carbon and sole nitrogen sources, antibiotics and dyestuff resistance, salt resistance and initial pH for growth, range of temperature for growth and urease reaction, as well as 16S rDNA PCR-RFLP analysis. The results showed that there were differences in utilization of sole carbon source, susceptibility of antibiotics and dyestuff resistance and no significant differences for utilization of sole nitrogen source for all the tested strains. Meanwhile the isolated rhizobium strains indicated high resistance to saline-alkali and high temperature. Through comparison analysis of numerical taxonomy and 16S rDNA PCR-RFLP, the tested strains had rich phenotypic and genetic diversities. At similarity level of 80 %, the tested strains clustered into two phenotypic groups and the differentiated features between two phenotypic groups were different. In dendrogram of numerical taxonomy, the clustered strains were also clustered together in dendrogram of tested rhizobium strains based on 16S rDNA PCR-RFLP. The results by using two methods are basically consistent.
出处
《农业科学研究》
2009年第3期14-20,27,共8页
Journal of Agricultural Sciences
基金
宁夏人事厅出国留学人员科研活动资助项目(2006164)
西部农林高校博士生访学研究基地项目(Fx-0602)
关键词
沙冬青
根瘤菌
表型多样性
多聚酶链式反应
限制性片段长度多态性
Ammopiptanthus mongolicus
rhizobia
phenotypic diversity
polymerase chain reaction
restriction fragment length polymorphism
