Putative endophytes of Miscanthus × giganteus were isolated, and screened in the laboratory, greenhouse and field for their plant growth promoting properties in this host. Pantoea ananatis and Pseudomonas savastanoi were the predominant bacteria in leaves whereas other pseudomonads prevailed in roots. Almost all fungal endophytes belonged to the Pezizomycotina and most were isolated from roots; Fusarium oxysporum was most abundant, followed by the genera Periconia, Exophiala, Microdochium and Leptodontidium. All endophytic groups produced phytohormones and some bacteria also produced siderophores, solubilised P and exhibited ACC-deaminase activity in vitro. In subsequent pot experiments with pre-selected endophytes, several isolates including pseudomonads, Variovorax paradoxus, Verticillium leptobactrum, Halenospora sp. and Exophiala sp. enhanced Miscanthus growth in gamma-sterilised soil. These promising Miscanthus-derived isolates were tested either as single or mixed inocula along with a mixed bacterial inoculum originating from poplar. No significant effects of inocula were detected in a pot experiment in non-sterilised soil. On two marginal field sites the mixture of bacterial endophytes from poplar had a consistently negative effect on survival and growth of Miscanthus. Contrarily, mixtures consisting of bacteria or fungi originating from Miscanthus promoted growth of their host, especially on the heavy metals-polluted site. The combination of bacteria and fungi was inferior to the mixtures consisting of bacteria or fungi alone. Our observations indicate extensive potential of mixed bacterial and fungal endophytic inocula to promote establishment and yield of Miscanthus grown on marginal and polluted land and emphasise the necessity to test particular microbial-plant host combinations. Morphotypes of fungi isolates from Miscanthus × giganteus.

Institute of Botany Czech Academy of Sciences Department of Mycorrhizal Symbioses Zámek 1 252 43 Průhonice Czech Republic

University of Chemistry and Technology Prague Technická 5 166 28 Praha 6 Czech Republic

References provided by Crossref.org

Plant Growth-Promoting Endophytic Bacteria Isolated from Miscanthus giganteus and Their Antifungal Activity

Bacterial and fungal endophyte communities in healthy and diseased oilseed rape and their potential for biocontrol of Sclerotinia and Phoma disease

Bioprospecting of a Novel Plant Growth-Promoting Bacterium Bacillus Altitudinis KP-14 for Enhancing Miscanthus × giganteus Growth in Metals Contaminated Soil