Abstract
Three salt-tolerantAzospirillum brasilense strains were isolated from the roots of finger millet grown in saline calcareous soil and characterized. The effect of various salts on growth and N2ase activity of these strains was tested and strain STR1 was found more tolerant at higher concentrations of Cl-, SO4 2 and HCO3 -. Bicarbonate was found to be the most toxic. The content and concentrations of root exudates of finger millet genotypes were different and chemotaxis to sugars, amino acids, organic acids and root exudates was strain specific. Under salt stress, significant interactions between strains and genotypes of finger millet resulted in different responses of N2ase activity, endo- and exorhizospheric population, dry weight of root, shoot and grain yield.
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Rai, R. Strain-specific salt tolerance and chemotaxis ofAzospirillum brasilense and their associative N-fixation with finger millet in saline calcareous soil. Plant Soil 137, 55–59 (1991). https://doi.org/10.1007/BF02187432
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DOI: https://doi.org/10.1007/BF02187432