Xanthomonas

Xanthomonas (from greek: xanthos – "yellow"; monas – "entity") is a genus of bacteria, many of which cause plant diseases. There are at least 27 plant associated Xanthomonas spp., that all together infect at least 400 plant species. Different species typically have specific host and/or tissue range and colonization strategies.

==Taxonomy== The genus Xanthomonas has been subject of numerous taxonomic and phylogenetic studies and was first described as Bacterium vesicatorium as a pathogen of pepper and tomato in 1921. Dowson later reclassified the bacterium as Xanthomonas campestris and proposed the genus Xanthomonas.Xanthomonas was first described as a monotypic genus and further research resulted in the division into two groups, A and B. Later work using DNA:DNA hybridization has served as a framework for the general Xanthomonas species classification. Other tools, including multilocus sequence analysis and amplified fragment-length polymorphism, have been used for classification within clades. While previous research has illustrated the complexity of the genus Xanthomonas, recent research appears to have resulted in a clearer picture. More recently, genome-wide analysis of multiple Xanthomonas strains mostly supports the previous phylogenies.