L'taief Boulbaba, Sifi Bouaziz, Gtari Maher, Zaman-Allah Mainassara, Lachaâl Mokhtar
Département de Biologie, Faculté de Sciences de Tunis, Campus Universitaire 1060, Tunisia.
Can J Microbiol. 2007 Mar;53(3):427-34. doi: 10.1139/w06-127.
Several phenotypic markers were used in this study to determine the biodiversity of rhizobial strains nodulating Cicer arietinum L. in various areas of Tunisia. They include symbiotic traits, the use of 21 biochemical substrates, and tolerance to salinity and pH. In addition, restriction fragment length polymorphisms (RFLPs) of PCR-amplified 16S rDNA were compared with those of reference strains. Numeric analysis of the phenotypic characteristics showed that the 48 strains studied fell into three distinct groups. This heterogeneity was highly supported by the RFLP analysis of 16S rRNA genes, and two ribotypes were identified. Chickpea rhizobia isolated from Tunisian soils are both phenotypically and genetically diverse. Results showed that 40 and 8 isolates were assigned, respectively, to Mesorhizobium ciceri and Mesorhizobium mediterraneum.
本研究使用了几种表型标记来确定突尼斯不同地区根瘤菌与鹰嘴豆结瘤的生物多样性。这些标记包括共生特性、对21种生化底物的利用情况以及对盐度和pH值的耐受性。此外，还将PCR扩增的16S rDNA的限制性片段长度多态性（RFLP）与参考菌株的进行了比较。对表型特征的数值分析表明，所研究的48个菌株分为三个不同的组。16S rRNA基因的RFLP分析有力地支持了这种异质性，并鉴定出两种核糖型。从突尼斯土壤中分离出的鹰嘴豆根瘤菌在表型和遗传上都具有多样性。结果表明，分别有40株和8株被鉴定为中慢生根瘤菌和地中海中慢生根瘤菌。
