[Estimation of abundance dynamics of gram-negative bacteria in soil].

Bacterial succession in soil was studied for two variants of initiation (moistening and moistening with addition of glucose). To determine the numbers of viable gram-negative bacteria, the modified nalidixic acid method was applied. The numbers of gram-negative bacteria revealed by this method were 2 to 3.5 times higher than those determined by the traditional method. In a developing community, the highest total bacterial numbers were observed on day 7; afterwards their numbers decreased and stabilized at a level exceeding four- to fivefold the initial one. In both experimental variants, the highest numbers of viable gram-negative bacteria were revealed on day 15 (75-85% of the total bacterial numbers). Morphology of these bacteria suggests their classification as cytophagas (chitinophagas) utilizing chitin from the dead fungal mycelium.