Induced Mutagenesis in Rhizobium trifolii

Department of Microbiology, University of Edinburgh, College of Agriculture, West Mains Road, Edinburgh EH9 3JG ABSTRACT SUMMARY: The efficiency of a variety of common mutagens in producing mutation in Rhizobium trifolii P3 was examined. Ethyl methanesulphonate, methyl methanesulphonate, decarbamoyl mitomycin C, nitrous acid and gamma radiation did not mutate R. trifolii P3. N -Methyl- N '-nitro- N -nitrosoguanidine (MNNG) and ultraviolet radiation were both mutagenic, the former being the more effective. Transposon mutagenesis with Tn5 yielded the same frequency and range of auxotrophs as did MNNG. Present address: Department of Genetics, University of Birmingham, P.O. Box 363, Birmingham B15 2TT.