Gao L F, Hu Z A, Wang H X
Key Laboratory of Photosynthesis and Environmental Molecular Physiology, Institute of Botany, Chinese Academy of Sciences, Beijing, China.
Lett Appl Microbiol. 2002;35(4):347-52. doi: 10.1046/j.1472-765x.2002.01192.x.
Thirty-three rhizobial strains isolated from nodules of Caragana intermedia in Maowusu sandland were examined for their genetic diversity and putative phylogenetic position.
Isolates from Caragana intermedia were classified into 12 genotypes by 16S rDNA polymerase chain reaction-restriction fragment length polymorphism (RFLP), which showed no distinct relationships with those of the reference strains. The genotypes of rhizobia were not related to geographical location. Thr 16S rDNA sequence of representative strain GH2001 from dominant genotype 2 shared high homologuey with some Rhizobium species: Rh. giardinii (96.4%), Rh. huautlense (95.3%), Rh. galegae (95.7%), Rh. yanglingense (95.2%), Rh. mongolense (95.6%), Rh. radiobacter (99%) and Rh. rubi (98.3%).
A high degree of genetic diversity existed among rhizobia nodulating Caragana intermedia in Maowusu sandland. Most of the new isolates might belong to Rhizobium.
The results suggest that the rich diversity of rhizobia might have contributed to the adaptation of the arid region. These strains could be valuable at the economic and ecosystem level.
对从毛乌素沙地中间锦鸡儿根瘤中分离出的33株根瘤菌菌株进行遗传多样性和假定系统发育位置的检测。
通过16S rDNA聚合酶链反应-限制性片段长度多态性（RFLP）分析，将中间锦鸡儿分离株分为12个基因型，这些基因型与参考菌株的基因型没有明显关系。根瘤菌的基因型与地理位置无关。优势基因型2的代表菌株GH2001的16S rDNA序列与一些根瘤菌物种具有高度同源性：贾氏根瘤菌（96.4%）、华特尔根瘤菌（95.3%）、山羊豆根瘤菌（95.7%）、杨凌根瘤菌（95.2%）、蒙古根瘤菌（95.6%）、放射形土壤杆菌（99%）和悬钩子根瘤菌（98.3%）。
毛乌素沙地中间锦鸡儿根瘤菌存在高度的遗传多样性。大多数新分离株可能属于根瘤菌属。
结果表明，丰富多样的根瘤菌可能有助于适应干旱地区。这些菌株在经济和生态系统层面可能具有重要价值。
