Quorum sensing in Pseudomonas savastanoi pv. savastanoi and Erwinia toletana: role in virulence and interspecies interactions in the olive knot

The olive-knot disease (Olea europea L.) is caused by the bacterium Pseudomonas savastanoi pv. savastanoi (PSV). PSV in the olive-knot undergoes interspecies interactions with the harmless endophyte Erwina toletana (ET); PSV and ET co-localize and form a stable community resulting in a more aggressive disease.