Culture-Dependent Approach for Determining Microbial Diversity in Soils from KCM/AGRIA Region

Abstract

Significant shifting of the microbial communities structure was detected in three metal-polluted soils collected around the Pb-Zn smelter KCM and the agrochemicals factory AGRIA, situated near the town of Plovdiv, Bulgaria. Industrial-, dumpsite- and agricultural soils were contaminated with As: 7.5-52.9 mg/kg; Hg: 0.086-0.404 mg/kg; Cd: 2.3-71.1 mg/kg; Mn: 742-1510 mg/kg; Pb: 138-2560 mg/kg; Cu: 32-268 mg/kg and Zn: 293-4490 mg/kg. Remarcable ecological disturbance was found in the agricultural soil using ecotoxicological test with type strain Pseudomonas putida DSM 50026 (ISO 10712). In order to assess ecologically relevant bacteria over twenty soil bacterial isolates were cultured. Six of them possess tolerance to one or more heavy metals. Four of the isolates demonstrated herbicide tolerance to 2,4-dichlorphenoxiacetic acid. Our results suggest that the microbial community responds to long-term metal- and pesticides contamination through changes in microbial community structure and selection for resistance.

*** and. *