We study the diversity, plasmid diversity and functionality, and evolution of the invasive bacterial pathogen Erwinia amylovora, cause of fire blight disease, and all related Erwinia species. Additionally, we investigate the biocontrol bacteria Pantoea agglomerans and Pantoea vagans using genomics and transcriptomics to elucidate mechanisms of action, increasing biocontrol activity and resolving biosafety concerns with these species. Working with collaborators in South Africa we are investigating the evolutionary genomics of beneficial and pathogenic Pantoea species.