The combination of molecular–genetic methods exploited in the present study may be used for investi- gating the microorganisms associated with macro- phytes. The enzymatic lysis technique with phenol– chloroform extraction is optimal for isolating bacterial total DNA from the natural samples and enriched cul- tures. Amplifying the sum DNA on the highly conser- vative primers at the two-stage reaction regime is rec- ommended. High genotype diversities of microorgan- isms associated with reed grass were obtained. These