Endophytic and rhizospheric bacterial communities isolated from the medicinal plants Echinacea purpurea and Echinacea angustifolia

In this work we analyzed the composition and structure of cultivable bacterial communities isolated from the stem/leaf and root compartments of medicinal plants Echinacea purpurea (L.) Moench and Echinacea angustifolia (DC.) Hell, grown in the same soil as well as the bacterial community from their rhizospheric soils. A combination of molecular PCR-based techniques was applied on cultivable bacteria isolated from the three compartments of the two plants. The results showed that the two plants were characterized by different communities, as well as the compartments of each plant, indicating that the degree of strain sharing was very low and suggesting a strong selective pressure within plant tissues. Pseudomonas genus was the most represented, together with Actinobacteria and Bacillus spp. It is possible that the presence of distinct bacterial communities between different plant species and among compartments of the same plant species might be related to the differences in medicinal properties of the two plants, and of the plant compartments.