三叶草、猪屎豆和含羞草植物根瘤菌16S rDNA PCR-RFLP分析和数值分类研究  

16S rDNA PCR-RFLP analysis and numerical taxonomy for rhizobia Isolated from Trifolium,Crotalaria and Mimosa

作　　者：刘晓云[1] 陈文新[1] 

机构地区：[1]中国农业大学生物学院

出　　处：《中国农业大学学报》2003年第3期1-6,共6页Journal of China Agricultural University

基　　金：国家自然科学基金资助项目 ( 39730 0 10 )

摘　　要：采用 16SrDNAPCR -RFLP分析和表型数值分类 ,对分离自三叶草 (Trifolium)、猪屎豆 (Crotalaria)和含羞草(Mimosa) 3属植物的根瘤菌进行了分类研究。 16SrDNAPCR -RFLP分析表明 ,在 80 %的相似性水平上 ,6 7株待测菌株和 18株参比菌株归属到慢生根瘤菌属 (Bradyrhizobium)、中慢生根瘤菌属 (Mesorhizobium)、土壤杆菌属 (Agrobac terium)和根瘤菌属 (Rhizobium)与中华根瘤菌属 (Sinorhizobium) 4个系统发育分支。进一步对其中 5 6株待测菌株和14株参比菌株进行表型性状数值分类研究 ,在 84 %的相似性水平上 ,得到 6个独立的类群 :群Ⅰ、Ⅳ和Ⅵ为新群 ,没有与参比菌株聚在一起 ;群Ⅱ包含慢生大豆根瘤菌 (Bradyrhizobiumjaponicum) ;群Ⅲ含根瘤菌属 (Rhizobium) 2个已知的代表菌株 ;群Ⅴ含土壤杆菌属 (Agrobacterium) 2个已知种的代表菌株。以上结果表明 ,分离自这 3属植物的根瘤菌菌株具有表型和遗传型多样性 ,同时新发现分离自三叶草的根瘤菌的慢生和中慢生菌株 ;分离自含羞草的根瘤菌的慢生菌株和分离自猪屎豆的根瘤菌的快生菌株 。Sixty-seven strains isolated from the root nodules of Trifolium, Crotalaria and Mimosa in comparison with 18 reference strains were analysed by 16S rDNA PCR-RFLP. At the similarity level of 80%, the examined strains were shown to belong to Bradyrhizobium, Agrobacterium, Mesorhizobium, Rhizobium and Sinorhizobium. The tested 56 strains and 14 reference strains were also studied by numerical taxonomy. Six clusters were formed at the similarity level of 84%, among which there are three new clusters, cluster Ⅰ, cluster Ⅳand cluster Ⅵ, in which there are no recognized type strains. ClusterⅡincluds strain of Bradyrhizobium japonicum, cluster Ⅲ includs two type strains of species of Rhizobium, cluster Ⅴ might be Agrobacterium. The results showed that these examined strains distributed in many rhizobial genera, showing a great diversity of rhizobia symbioses with above mentioned legumes. We also discovered that slow growers and moderate slow growers of rhizobia form symbiosis with Trifolium, slow growers with Mimosa and fast growers with Crotalaria.

关 键 词：三叶草 猪屎豆 含羞草 植物根瘤菌 16SrDNA PCR-RFLP分析 数值分类 遗传型多样性 

分 类 号：Q939.114[生物学—微生物学]