1. The cypsela (achene) of Echinacea purpurea as a diffusion unit of a community of microorganisms
- Author
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Fabio Firenzuoli, Renato Fani, Valentina Maggini, Marian Viola, T. Faddetta, Patrizia Bogani, Anna Maria Puglia, Massimiliano Cardinale, Elisangela Miceli, Alessio Papini, Silvia Schiff, Corrado Tani, Cardinale, M, Viola, M, Miceli, E, Faddetta, T, Puglia, AM, Maggini, V, Tani, C, Firenzuoli, F, Schiff, S, Bogani, P, Fani, R, Papini, A, Cardinale, Massimiliano, Viola, Marian, Miceli, Elisangela, Faddetta, Teresa, Puglia, Anna Maria, Maggini, Valentina, Tani, Corrado, Firenzuoli, Fabio, Schiff, Silvia, Bogani, Patrizia, Fani, Renato, and Papini, Alessio
- Subjects
Achene ,Hypha ,Endophytic bacteria ,Settore BIO/19 - Microbiologia Generale ,Plant Roots ,Applied Microbiology and Biotechnology ,Echinacea ,03 medical and health sciences ,Paenibacillus ,Environmental Biotechnology ,Perianth ,Botany ,Cypsela ,Soil Microbiology ,Echinacea purpurea ,030304 developmental biology ,0303 health sciences ,Bacteria ,biology ,Plant Extracts ,030306 microbiology ,Pantoea ,Fungi ,food and beverages ,General Medicine ,biology.organism_classification ,Plant Leaves ,Germination ,Anatomy ,Echinacea, Echinacea purpurea, Endophytic bacteria, Fungi, Anatomy, Cypsela, Perianth ,Biotechnology - Abstract
Echinacea purpurea is a plant cultivated worldwide for its pharmaceutical properties, mainly related to the stimulation of the immune system in the treatment of respiratory infections. The cypselas (fruits) of E. purpurea were examined in order to investigate the presence, localization and potential function(s) of endophytic microorganisms. Electron and confocal microscopy observations showed that three different components of microorganisms were associated to cypselas of E. purpurea: (i) one endocellular bacterial component in the cotyledons, enclosed within the host membrane; (ii) another more generic bacterial component adhering to the external side of the perianth; and (iii) a fungal component inside the porous layer of the perianth, the woody and porous modified residual of the flower, in the form of numerous hyphae able to cross the wall between adjacent cells. Isolated bacteria were affiliated to the genera Paenibacillus, Pantoea, and Sanguibacter. Plate tests showed a general resistance to six different antibiotics and also to an antimicrobial-producing Rheinheimera sp. test strain. Finally, microbiome-deprived E. purpurea seeds showed a reduced ability to germinate, suggesting an active role of the microbiome in the plant vitality. Our results suggest that the endophytic bacterial community of E. purpurea, previously found in roots and stem/leaves, might be already carried at the seed stage, hosted by the cotyledons. A further microbial fungal component is transported together with the seed in the perianth of the cypsela, whose remarkable structure may be considered as an adaptation for fungal transportation, and could influence the capability of the seed to germinate in the soil.Key Points• The fruit of Echinacea purpurea contains fungi not causing any damage to the plant.• The seed cotyledons contain endocellular bacteria.• Seed/fruit deprived of the microbiome showed a reduced ability to germinate.
- Published
- 2021