Effect of Azospirillum brasilense coinoculated with Rhizobium on Phaseolus vulgaris flavonoids and Nod factor production under salt stress

• Published in: Soil biology & biochemistry Vol. 40; no. 11; pp. 2713 - 2721
• Main Authors: Dardanelli, Marta S., Fernández de Córdoba, Francisco J., Espuny, M. Rosario, Rodríguez Carvajal, Miguel A., Soria Díaz, María E., Gil Serrano, Antonio M., Okon, Yaacov, Megías, Manuel
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier Ltd 01-11-2008; Elsevier
• Subjects: Abiotic stress; Agronomy. Soil science and plant productions; Azospirillum brasilense; beans; Biochemistry and biology; Biological and medical sciences; chemical constituents of plants; Chemical, physicochemical, biochemical and biological properties; Coinoculation; field crops; Flavonoids; Fundamental and applied biological sciences. Psychology; gene expression; nitrogen-fixing bacteria; Nod factors; nod-gene expression; nodulation; nodulation factors; oligosaccharides; Phaseolus vulgaris; Physics, chemistry, biochemistry and biology of agricultural and forest soils; plant growth-promoting rhizobacteria; Rhizobium; Rhizobium etli; Rhizobium tropici; root exudates; root growth; root nodules; roots; salinity; salt stress; seedlings; Soil science; strains; symbionts; symbiosis; Flavonoids; Rhizobium etli; Nod factors; Abiotic stress; Coinoculation; Azospirillum brasilense; Rhizobium tropici; nod-gene expression; Spirillaceae; Environmental factor; Flavonoid; Abiotic factor; Lipochitooligosaccharide; Inoculation; Dicotyledones; Angiospermae; Production factor; Bacteria; Soil science; Spirillales; Oligosaccharide; Nodulation; Gene expression; Symbiont; Stress; Salinity; Grain legume; Leguminosae; Vegetable crop; Phaseolus vulgaris; Spermatophyta; Rhizobiaceae
• ISSN: 0038-0717; 1879-3428
• DOI: 10.1016/j.soilbio.2008.06.016

The effects of salt upon
Azospirillum brasilense strain Cd on plant growth, nodulation, flavonoid and lipochitooligosaccharide (LCOs-Nod factor) production, were sequentially followed after 4, 7 and 14
days during a
Rhizobium-
Phaseolus vulgaris cv. Negro Jamapa interaction, in a hydroponics growth system.
Azospirillum brasilense promoted root branching in bean seedling roots and increased secretion of
nod-gene-inducing flavonoid species, as detected by high-performance liquid chromatography (HPLC). The results also support that
A. brasilense allows a longer, more persistent exudation of flavonoids by bean roots. A general positive effect of
Azospirillum-
Rhizobium coinoculation on the expression of
nod-genes by
Rhizobium tropici CIAT899 and
Rhizobium etli ISP42, and on nodulation factor patterns, was observed in the presence of root exudates. The negative effects obtained under salt stress on
nod-gene expression and on Nod factors' appearance were relieved in coinoculated plants.