Evaluation of bradyrhizobia strains isolated from field-grown soybean plants in Argentina as improved inoculants

Bradyrhizobium strains were isolated from nodules obtained from field-grown soybean plants sampled in 12 soybean production locations in Argentina. These fields had been annually cropped with soybean and did not show decreases in yields even though they had been neither N-fertilized nor inoculated f...

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Detalles Bibliográficos
Autores: Melchiorre, Mariana, De Luca, Marcos Javier, Gonzalez Anta, Gustavo, Suarez, Paola Alejandra, Lopez, Carlos, Lascano, Hernan Ramiro, Racca, Roberto Walter
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2010
País:Argentina
Institución:Instituto Nacional de Tecnología Agropecuaria
Repositorio:INTA Digital (INTA)
Idioma:inglés
OAI Identifier:oai:localhost:20.500.12123/10934
Acceso en línea:http://hdl.handle.net/20.500.12123/10934
https://link.springer.com/article/10.1007/s00374-010-0503-7
https://doi.org/10.1007/s00374-010-0503-7
Access Level:acceso abierto
Palabra clave:Bradyrhizobium japonicum
Soja
Argentina
Biological Nitrogen Fixation
Soybeans
Fijación Biológica del Nitrógeno
Inoculant
Descripción
Sumario:Bradyrhizobium strains were isolated from nodules obtained from field-grown soybean plants sampled in 12 soybean production locations in Argentina. These fields had been annually cropped with soybean and did not show decreases in yields even though they had been neither N-fertilized nor inoculated for at least the last 5 years. We hypothesized that the isolated strains maintained high competitiveness and efficiency in fixing adequate N2 levels. A set of strains that showed the highest nodular occupancy in each sampling location were assayed for symbiotic performance under greenhouse and field conditions and comparatively evaluated with Bradyrhizobium japonicum E109, the strain officially recommended for inoculant formulation in Argentina. An inoculant pool, formed by four strains obtained from nodules collected from Cañada Rica, developed higher nodular biomass than B. japonicum E 109 in assays carried out in greenhouses under well irrigated conditions. Additionally, neither nodule production nor specific nitrogenase activity decreased with respect to B. japonicum E 109 when plants were drought stressed during 7 days from sowing. The mean yields obtained under field conditions and plotted against the principal component one (CP1) obtained with an additive main effect and multiplicative interaction (AMMI) model showed that the inoculant pool from Cañada Rica had higher contribution to yield than strain E 109, although with lower environmental stability. The inoculant pool from Cañada Rica could be considered an improved inoculant and be used for preliminary assays, to formulate inoculants in Argentina.