Culturable bacterial endophytes from sedimentary humic acid-treated plants

The global decrease in soil fertility leads to a new agricultural scenario where eco-friendly solutions play an important role. The plant growth promotion through the use of microbes, especially endophytes and rhizosphere microbiota, has been proposed as a useful solution. Several studies have shown...

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Detalles Bibliográficos
Autores: Hita-Mejía, D. (David) de|||/items/e985ff71-0b95-42e6-a1ba-911ee454bb5c, Fuentes-Ramirez, M. (Marta)|||/items/6099cef4-7f6e-43d9-8530-7bc85af2af88, Zamarreño-Arregui, A.M. (Angel María)|||/items/316fe376-3b6c-4f68-b6da-03cf1fdab968, Ruiz-Zabalza, Y. (Yaiza)|||/items/e39eb956-2166-4f4d-8360-f3fbca23edf2, García-Mina, J.M. (José María)|||/items/815053fc-2f39-4f00-aed0-c5f6ee370258
Tipo de recurso: artículo
Fecha de publicación:2020
País:España
Institución:Universidad de Navarra
Repositorio:Dadun. Depósito Académico Digital de la Universidad de Navarra
Idioma:inglés
OAI Identifier:oai:dadun.unav.edu:10171/59574
Acceso en línea:https://hdl.handle.net/10171/59574
Access Level:acceso abierto
Palabra clave:Endophyte
Plant growth promotion
Microbiota
Humic
Phosphate solubilizing bacteria
Cucumber
Descripción
Sumario:The global decrease in soil fertility leads to a new agricultural scenario where eco-friendly solutions play an important role. The plant growth promotion through the use of microbes, especially endophytes and rhizosphere microbiota, has been proposed as a useful solution. Several studies have shown that humic substances are suitable vehicles for the inoculation of plant growth promoting bacteria, and that this combination has an enhanced effect on the stimulation of plant development. In this work, cucumber plants grown hydroponically have been pre-treated with a sedimentary humic acid (SHA) with known plant growth-enhancing effects, and culturable bacterial endophytes have been isolated from these plants. The hypothesis was that this pre-treatment with SHA could lead to the isolation of certain endophytic taxa whose proliferation within the plant could have been promoted as a result of the effects of the treatment with SHA, and that could eventually reinforce a potential synergistic effect of a combined application of those endophytic bacteria and SHA. The culturable endophytes that have been isolated from humic acid-treated cucumber plants have been identified as members of four main phyla:Proteobacteria,Firmicutes,Actinobacteria, andBacteroidetes. Isolates were characterized according to the following plant growth-promoting traits: nitrogen fixation/scavenging, phosphate solubilization, siderophore production and plant hormone production. Most of the isolates were able to fix/scavenge nitrogen and to produce plant hormones (indole-3-acetic acid and several cytokinins), whereas few isolates were able to solubilize phosphate and/or produce siderophores. The most promising endophyte isolates for its use in futures investigations as plant growth-promoting bacterial inocula werePseudomonassp. strains (that showed all traits),Sphingomonassp.,Stenotrophomonassp. strains, or someArthrobactersp. andMicrobacteriumsp. isolates.