Phylodynamic insights into global emergence and diversification of the tomato pathogen Xanthomonas hortorum pv. gardneri.

ABSTRACT.- The emergence of plant pathogens is often associated with waves of unique evolutionary and epidemiological events. Xanthomonas hortorum pv. gardneri is one of the major pathogensca using bacterial spot disease of tomatoes. After its frst report in the 1950s, there were no formal reports on this pathogen until the 1990s, despite active global research on the pathogens that cause tomato and pepper bacterial spot disease. Given the recently documented global distribution of X. hortorum pv. gardneri, our objective was to examine genomic diversification associated with its emergence.