Abstract

The objective of this study was to investigate the effects of salt, fungicide, herbicide, antibiotics, heavy metal on growth of Rhizobium isolates from root nodules of Trifolium species from Åžanliurfa, Turkey. All of the isolates, expect TC2 were found to tolerate a relatively high salt concentration. None of the isolates grew at pH 4 and four isolates grew at pH 4.5. All of the rhizobial isolates showed resistance to streptomycin sulphate, chloramphenicol, ampicillin, penicillin G and kanamycin and to Zn (0.1 g L-1). T4 isolate showed sensitivity to penicillin G and kanamycin. Isolates were tested for their tolerance to fungicide or herbicide. The effect of the pesticides on the rhizobial isolates was variable, depending on the fungicide or herbicide and the isolate.

Key words: Trifolium species, isolate, NaCl, antibiotics, pH, heavy metal, pesticide.