Table 1.

Effect of salt stress on growth of rhizobial species in LAS minimal medium and utilization of choline and glycine betaine as sole carbon and nitrogen sources

SpeciesGrowth in LAS medium with:Growth rate in S medium withc:
No salt, ratea0.1 M NaCl0.2 M NaClChoGB
RateYieldbRateYield
R. leguminosarum bv. viciae3.8NGd NG7.87.5
R. leguminosarum bv. trifolii3.6NG NG6.85.6
R. leguminosarum bv. phaseoli3.0NG NG7.39.8
R. tropiciIIA10.86.715NGNDe ND
R. tropici IIB9.46.41004.4305.05.1
A. rhizogenes 8.2NG NG6.44.1
S. meliloti 15.315.31009.91009.59.9
S. fredii 15.49.91005.9659.88.9
R. etli 6.4NG NG7.49.6
R. galegae 3.52.515NG4.25.4
A. tumefaciens 7.78.31008.91007.213.2
M. loti 3.92.920NG4.04.3
M. huakuii 3.92.8352.72410.18.5
B. japonicum 3.1NG NGNG NG
  • a The rate is expressed as the number of generations per hour (102) determined during the logarithmic phase. For every growth experiment, data are the averages of results of at least three different repeats with a standard deviation of less than 10%.

  • b The yield is the cell density (optical density at 600 nm) reached at the stationary phase. A value of 100% corresponds to the optical density obtained with cells grown in the absence of salt.

  • c Choline (Cho) or glycine betaine (GB) was added to carbon- and nitrogen-free S medium at a concentration of 10 mM.

  • d NG, no growth.

  • e ND, not determined.