[Tolerance of soil bacterial complexes to salt shock]

Investigations showed that bacteria present in soil are resistant to one-day exposure to a saturated solution of ammonium nitrate and can well develop when transferred to laboratory nutrient media. The evaluated number of bacteria in NH4NO3-treated soil samples was nearly the same as in native soil samples, while was 1.5-2.5 times smaller in the former than in the latter case when microbial succession in the soil samples was initiated by wetting them. Bacteria (particularly gram-negative ones) occurring at the early stages of succession were the most sensitive to salt stress. Bacteria in soil were found to be much more resistant to salt stress than the same bacteria isolated in pure cultures.