Poster #12

Seed-associated microbial diversity in invasive plants threatening southern Andean ecosystems
MIGUEL SOBARZO, CRISTIANE SAGREDO-SAEZ, ALEJANDRA FUENTES-QUIROZ, HÉCTOR HERRERA
Laboratorio de Silvicultura, Departamento de Ciencias Forestales, Facultad de Ciencias Agropecuarias y Medioambiente, Universidad de La Frontera, 4811230 Temuco, Chile

The pristine forests of the Andes are globally recognized as biodiversity hotspots and potential carbon sinks. However, exotic species such as Ulex europaeus, Acacia dealbata, and Lupinus polyphyllus have invaded these ecosystems despite the adverse climatic conditions found in the high mountains of the southern Andes. In this study, we aimed to characterize the diversity of seed-associated microorganisms in invasive species threatening native environments in southern South America using a fungal and bacterial metabarcoding approach. The number of OTUs was higher in bacteria (~320) than in fungi (~180) in the three species. Proteobacteria and Ascomycota were the most abundant phyla, with the genera Herbaspirillum, Pseudomonas, Exophiala, Cladosporium, and Ramularia being the most abundant taxa. The distribution of the microbial communities was strongly influenced by the source of the invasive species, showing a significant abundance of potentially plant growth promoting microorganisms such as Herbaspirillum sp., Mucilaginibacter sp., Pseudomonas sp. and Flavobacterium sp., as well as the beneficial yeasts Aureobasidium and Sporobolomyces with demonstrated biocontrol capabilities against phytopathogenic fungi. Overall, this study confirms that invasive species can promote the transfer of recognized beneficial microorganisms to their seeds, which can be an additional mechanism contributing to the plant invasiveness in harsh Andean ecosystems.