Search results for "mesorhizobium"
showing 5 items of 5 documents
Diversity of rhizobia nodulating wild shrubs of Sicily and some neighbouring islands
2008
Abstract Legume shrubs have great potential for rehabilitation of semi-arid degraded soils in Mediterranean ecosystems as they establish mutualistic symbiosis with Nfxing rhizobia. Eighty-eight symbiotic rhizobia were isolated from seven wild legume shrubs native of Sicily (Southern Italy) and grouped in operational taxonomic units (OTU) by analysis of the ribosomal internal transcribed spacer (ITS) polymorphism. Partial sequencing of 16S rRNA gene of representative isolates of each OTU revealed that most Genisteae symbionts are related to Bradyrhizobium canariense, B. japonicum and B. elkanii. Teline monspessulana was the only Genistea nodulated by Mesorhizobium strains, and Anagyris foeti…
Conservation of type III secretion system genes inBradyrhizobiumisolated from soybean
2006
International audience; The distribution of rhcRST genes encoding the type III secretion system (T3SS) in a collection of Bradyrhizobium strains was characterized by PCR and Southern blot hybridization. The polymorphism of the corresponding sequences amplified by PCR was characterized by RFLP and sequencing together with those available in the databank. Genomic group I is characterized by the presence of Bradyrhizobium elkanii strains and group II by the presence of B. japonicum and B. liaoningense strains. Highly conserved T3SS-like genes were detected by PCR in all Bradyrhizobium strains isolated from soybean belonging to genomic group II, and in none of the strains belonging to genomic g…
SIMBIONTI RADICALI DI ASTRAGALUS NEBRODENSIS (GUSS.) STROBL.
2013
Le leguminose spontanee mediterranee hanno un elevato potenziale nei processi di rinaturalizzazione di ecosistemi degradati o semiaridi poiché stabiliscono simbiosi radicali con batteri azoto-fissatori e funghi micorrizici i quali, agendo sinergicamente, avvantaggiano la pianta per la nutrizione e la resistenza agli stress. Astragalus nebrodensis è un arbusto perenne appartenente alla famiglia delle Fabaceae, endemico in Sicilia; i simbionti radicali di questa specie non sono noti. Gli obiettivi di questo studio sono stati: 1) l’analisi della diversità dei rizobi simbionti di Astragalus nebrodensis; 2) la valutazione dell’effetto dell’inoculo di rizobi da collezione e di funghi micorrizici …
Phylogenetic comparison of symbiotic (nodC and nifH) and 16S rRNA genes in strains of Rhizobium, Mesorhizobium and Bradyrhizobium isolated from Astra…
2000
Various studies reported different conclusions on the phylogenetic relationship between symbiotic (nod and nif) and chromosomal (16S rRNA) genes in rhizobia (Haukka et al, 1998). Some studies suggested that the phylogeny of nod genes could be related with the host plant (Ueda et al., 1995). In a previous study, rhizobia (44 isolates) from Astragalus, Oxytropis and Onobrychis pp have been classified into 14 distinct 16S rRNA gene types independently of their host plant and geographic origin. The majority of isolates were classified within the genus Mesorhizobium, and few within Rhizobium and Bradyrhizobium genera (Laguerre et al., 1997). The aim of the present study was to determine the dive…
Characterization of rhizobia nodulating chickpea in Tunisia
2001
Cent cinquante rhizobia nodulant le pois chiche (Cicer arietinum L.) ont ete isoles a partir de sols echantillonnes dans differentes regions de Tunisie. L'inoculation de la plante hote avec ces isolats montre une variabilite dans le temps d'apparition des premieres nodosites. Cinq isolats induisent des nodosites deux semaines apres inoculation alors que pour les 145 isolats restants les nodosites ne sont observees qu'apres au moins quatre semaines. L'etude par PCR/RFLP de l'ADNr 16S a permis de rattacher les isolats du premier groupe a l'espece Mesorhizobium mediterraneum et ceux du second groupe a l'espece Sinorhizobium medicae. La position taxonomique des isolats a ete confirmee par leurs…