Padilla-Gálvez, NataliaLuengo-Uribe, PaolaMancilla, SandraMaurin, AmandineTorres, ClaudiaRuiz, PamelaFrance, AndrésAcuña, IvetteUrrutia, Homero2023-06-152023-06-152021-12BMC Microbiology. Volume 21, Issue 1. December 2021. Article number 3351471-2180https://repositorio.unab.cl/xmlui/handle/ria/50782Indexación: Scopus.Background: The native potatoes (Solanum tuberosum subsp. tuberosum L.) grown in Chile (Chiloé) represent a new, unexplored source of endophytes to fnd potential biological control agents for the prevention of bacterial diseases, like blackleg and soft rot, in potato crops. Result: The objective of this study was the selection of endophytic actinobacteria from native potatoes for antago‑ nistic activity against Pectobacterium carotovorum subsp. carotovorum and Pectobacterium atrosepticum, and their potential to suppress tissue maceration symptoms in potato tubers. This potential was determined through the quorum quenching activity using a Chromobacterium violaceaum ATCC 12472 Wild type (WT) bioassay and its colo‑ nization behavior of the potato plant root system (S. tuberosum) by means of the Double labeling of oligonucleotide probes for fuorescence in situ hybridization (DOPE-FISH) targeting technique. The results showed that although Strep tomyces sp. TP199 and Streptomyces sp. A2R31 were able to inhibit the growth of the pathogens, only the Streptomyces sp. TP199 isolate inhibited Pectobacterium sp. growth and diminished tissue maceration in tubers (p≤0.05). Streptomy ces sp. TP199 had metal-dependent acyl homoserine lactones (AHL) quorum quenching activity in vitro and was able to colonize the root endosphere 10 days after inoculation. Conclusions: We concluded that native potatoes from southern Chile possess endophyte actinobacteria that are potential agents for the disease management of soft rot and blackleg.enEndophytic ActinobacteriaStreptomyces sp.Quorum QuenchingConfocal Laser MicroscopyBlacklegSoft RotPotatoArtículoAtribution 4.0 International (CC BY 4.0)10.1186/s12866-021-02393-x