Submitted to: Plant Pathogenic Bacteria: Genomics & Molecular Biology
Publication Type: Book / chapter
Publication Acceptance Date: 2/11/2008
Publication Date: 9/15/2008
Citation: Vinatzer, B., Bull, C.T. 2009. The impact of genomic approaches on our understanding of diversity and taxonomy of plant pathogenic bacteria. Pages 37-61. In Plant Pathogenic Bacteria: Genomics & Molecular Biology, R.W. Jackson Ed. Caister Academic Press, Norfolk, UK. Interpretive Summary: While it is easy to recognize different animals for example dogs versus cats, it is difficult to recognize bacteria or to group them together with other organisms to which they are related. This is partially because they are microscopic and because they have very few visually distinguishing features. As bacteriologists develop new methods for identifying bacteria, bacterial species concepts change based on the data collected. This influences plant pathologists and the public because the accurate identification and naming of a pathogen is important to tapping into the scientific literature for what is known about the pathogen and thus, is the first step in reducing the impact of plant diseases on food and fiber production. This work analyzes major technological developments in our ability to distinguish between and among groups of bacteria and how developing technology influences or concepts of bacterial species. The author’s work and that of others is used to demonstrate how advanced technologies and developing species concepts influence our understanding of bacterial plant pathogens.
Technical Abstract: Our understanding of the diversity of bacterial plant pathogens has changed dramatically over the past 100 years. Initially it was thought that each newly described disease was caused by a distinct plant pathogen species. Later, similarities in the physiology of these pathogens as well as inadequate records of type specimens resulted in many of the original species being grouped together regardless of demonstrated diversity, in particular regardless of their host range. We have now entered an era in which genomic approaches can reveal genetic diversity in much finer detail. This has resulted in the development of phylogenetic trees, which identify theoretical groupings at ranks below the level of the currently described bacterial plant pathogen species. There are cases in which these groupings coincide with previously defined species while in other cases these groups represent biologically or ecologically relevant groups that still need to be defined taxonomically. In this chapter we give an overview of the history of systematics and taxonomy, describe current genomics approaches to uncover diversity, and finally discuss which consequences the already uncovered genomic diversity in some of the current plant bacterial species could have on their taxonomy.