title: Alkalinity of Lanzarote soils is a factor shaping rhizobial populations with Sinorhizobium meliloti being the predominant microsymbiont of Lotus lancerottensis.
abstract: Lotus lancerottensis is an endemic species that grows widely throughout Lanzarote Island (Canary Is.). Characterization of 48 strains isolated from root nodules of plants growing in soils from eleven locations on the island showed that 38 isolates (79.1%) belonged to the species Sinorhizobium meliloti, whereas only six belonged to Mesorhizobium sp., the more common microsymbionts for the Lotus. Other genotypes containing only one isolate were classified as Pararhizobium sp., Sinorhizobium sp., Phyllobacterium sp. and Bradyrhizobium-like. Strains of S. meliloti were distributed along the island and, in most of the localities they were exclusive or major microsymbionts of L. lancerottensis. Phylogeny of the nodulation nodC gene placed the S. meliloti strains within symbiovar lancerottense and the mesorhizobial strains with the symbiovar loti. Although strains from both symbiovars produced effective N2-fixing nodules, S. meliloti symbiovar lancerottense was clearly the predominant microsymbiont of L. lancerottensis. This fact correlated with the better adaptation of strains of this species to the alkaline soils of Lanzarote, as in vitro characterization showed that while the mesorhizobial strains were inhibited by alkaline pH, S. meliloti strains grew well at pH 9.
authors.affiliation: Departamento de Bioquímica, Microbiología, Biología Celular y Genética, Universidad de La Laguna, 38200 La Laguna, Tenerife, Canary Islands, Spain. Electronic address: mileonba@ull.es.
authors.forename: Milagros
authors.initials: M
authors.lastname: León-Barrios
authors.affiliation: Departamento de Bioquímica, Microbiología, Biología Celular y Genética, Universidad de La Laguna, 38200 La Laguna, Tenerife, Canary Islands, Spain.
authors.forename: Juan
authors.initials: J
authors.lastname: Pérez-Yépez
authors.affiliation: Departamento de Bioquímica, Microbiología, Biología Celular y Genética, Universidad de La Laguna, 38200 La Laguna, Tenerife, Canary Islands, Spain.
authors.forename: Paola
authors.initials: P
authors.lastname: Dorta
authors.affiliation: Granja Agrícola Experimental, Área de Agricultura y Ganadería, Cabildo de Lanzarote, Canary Islands, Spain.
authors.forename: Ana
authors.initials: A
authors.lastname: Garrido
authors.affiliation: Departamento de Biología Animal, Edafología y Geología, Universidad de La Laguna, 38200 La Laguna, Tenerife, Canary Islands, Spain.
authors.forename: Concepción
authors.initials: C
authors.lastname: Jiménez
mesh_terms: D005798:Genes, Bacterial; D006863:Hydrogen-Ion Concentration; D000070116:Lotus / Q000382:microbiology*; D058885:Multilocus Sequence Typing; D010641:Phenotype; D010802:Phylogeny; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D012231:Rhizobium / Q000145:classification* / Q000235:genetics / Q000378:metabolism; D055049:Salt Tolerance / Q000235:genetics; D017422:Sequence Analysis, DNA; D016962:Sinorhizobium meliloti / Q000145:classification* / Q000235:genetics / Q000378:metabolism; D012987:Soil / Q000737:chemistry*; D012988:Soil Microbiology; D013312:Stress, Physiological; D013559:Symbiosis
chemical_list: D012336:RNA, Ribosomal, 16S; D012987:Soil
keywords: Alkaline soils; Lanzarote; Lotus; Mesorhizobium; Sinorhizobium; Symbiovars