Search

The Biolog system was evaluated with respect to analysing the diversity of bacterial terrestrial communities. Identification tests with authentic strains of typical soil bacteria belonging to Gram negative bacteria and the Bacillus-Clostridium-Streptococcus branch of Gram positive bacteria provided excellent results, whereas only 80% of the strains belonging to the Actinomycetes branch could be identified correctly. The identification rates for isolates from two terrestrial ecosystems were unsatisfactory (70% in Gram negative bacteria, 35% in Gram positive). The low number of isolates which can be reliably identified considerably limits the usefulness of the Biolog system for analysing the composition of autochthonous bacterial soil communities. The identification results must be confirmed by additional investigations.

The purpose of our study was to investigate the possibility of using the BIOLOG System for a rapid identification of various phytopathogenic bacteria (all in all 19 strains) from different vegetable crops. The results of the study have shown that the BIOLOG System indeed enables a rapid identification of numerous strains of phytopathogenic bacteria belonging to the species Pseudomonas syringae, Xanthomonas campestris and Erwinia carotovora. After four, six or twenty - four hours of incubation, identification down to the level of pathovar (Ps.pv. phaseolicola, P.s.pv. syringae, P.s.pv. tomato, X.c.pv. phaseoli and Xc.pv. vesicatoria) or subspecies (E.c.ssp. carotovora and E.c.ssp. atroseptica) was possible for 14 out of 19 investigated strains. For the others, the identification proved correct at the level of species or genus. Some pathovars were wrongly identified.

Changes in hydrocarbon content in soils resulted in characteristic shifts of the substrate utilization patterns as tested with the Biolog system. The altered patterns of substrate utilization corresponded to similar changes in abundance of hydrocarbon-utilizing bacteria and the occurrence of specific bacterial groups in the soils. Substrate utilization patterns as recorded with the Biolog system are suitable for rapidly assessing dynamics of autochthonous soil communities and evaluating their biodegradative potential.