title: Antagonistic interactions between endophytic cultivable bacterial communities isolated from the medicinal plant Echinacea purpurea.
abstract: In this work we have studied the antagonistic interactions existing among cultivable bacteria isolated from three ecological niches (rhizospheric soil, roots and stem/leaves) of the traditional natural medicinal plant Echinacea purpurea. The three compartments harboured different taxonomic assemblages of strains, which were previously reported to display different antibiotic resistance patterns, suggesting the presence of differential selective pressure due to antagonistic molecules in the three compartments. Antagonistic interactions were assayed by the cross-streak method and interpreted using a network-based analysis. In particular 'within-niche inhibition' and 'cross-niche inhibition' were evaluated among isolates associated with each compartment as well as between isolates retrieved from the three different compartments respectively. Data obtained indicated that bacteria isolated from the stem/leaves compartment were much more sensitive to the antagonistic activity than bacteria from roots and rhizospheric soil. Moreover, both the taxonomical position and the ecological niche might influence the antagonistic ability/sensitivity of different strains. Antagonism could play a significant role in contributing to the differentiation and structuring of plant-associated bacterial communities.
authors.affiliation: Department of Biology, University of Florence, Via Madonna del Piano 6, Sesto Fiorentino, Florence, I-50019, Italy.
authors.forename: Isabel
authors.initials: I
authors.lastname: Maida
authors.affiliation: Department of Biology, University of Florence, Via Madonna del Piano 6, Sesto Fiorentino, Florence, I-50019, Italy.|CRA-ABP Consiglio per la ricerca in agricoltura e l'analisi dell'economia agraria, Centro di ricerca per l'Agrobiologia e la Pedologia, Piazza M. D'Azeglio 30, Firenze, FI, 50121, Italy.
authors.forename: Carolina
authors.initials: C
authors.lastname: Chiellini
authors.affiliation: Department of Biology, University of Florence, Via Madonna del Piano 6, Sesto Fiorentino, Florence, I-50019, Italy.
authors.forename: Alessio
authors.initials: A
authors.lastname: Mengoni
authors.affiliation: Department of Biology, University of Florence, Via Madonna del Piano 6, Sesto Fiorentino, Florence, I-50019, Italy.
authors.forename: Emanuele
authors.initials: E
authors.lastname: Bosi
authors.affiliation: Center for Integrative Medicine, Careggi University Hospital, University of Florence, Florence, Italy.
authors.forename: Fabio
authors.initials: F
authors.lastname: Firenzuoli
authors.affiliation: Department of Biology, University of Florence, Via Madonna del Piano 6, Sesto Fiorentino, Florence, I-50019, Italy.
authors.forename: Marco
authors.initials: M
authors.lastname: Fondi
authors.affiliation: Department of Biology, University of Florence, Via Madonna del Piano 6, Sesto Fiorentino, Florence, I-50019, Italy.
authors.forename: Renato
authors.initials: R
authors.lastname: Fani
mesh_terms: D001419:Bacteria / Q000145:classification / Q000235:genetics / Q000254:growth & development / Q000302:isolation & purification*; D020900:Echinacea / Q000382:microbiology*; D060026:Endophytes / Q000145:classification / Q000235:genetics / Q000254:growth & development / Q000302:isolation & purification*; D018515:Plant Leaves / Q000382:microbiology; D018517:Plant Roots / Q000382:microbiology; D018547:Plant Stems / Q000382:microbiology; D010946:Plants, Medicinal / Q000382:microbiology*