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Taxonomy
of plant pathogenic bacteria
Abstract.
Bacterial
taxonomy includes three interrelated activities: classification
which involves the allocation
of organisms into groups; nomenclature - the naming of taxa
defined by classification, and identification - the process by
which unidentified organisms are referred to a taxa. There are
three alternative
concepts of classification: phenetic, phylogenetic and polyphasic.
The polyphasic approach
to a classification has a widespread support, though there is a
tendency to allow comparative sequence analyses of 16S rDNA to
determine classifications contrary to the indications of other
data. The latest revisions of bacterial classification based on
16S rDNA data, which in consequence lead to incomplete and
sometimes confusing revisions of nomenclature. These trends in
systematics also concern plant pathogenic bacteria. In February
2002 the International Committee for the Systematics
of Prokaryotes concluded that both phenotype and genotype play
important role in the species
description. The ecological role can also decide on the species
status. For example plant pathogen which caused unique and
dangerous for plants symptoms, may continue to bear names that
arę not necessarily in agreement with their genomic relatedness
in order to avoid confusion among
plant pathologists.
1. Introduction.
2. Systematic of plant pathogenic bacteria. 2.1. Nomenclature.
2.2. Identification. 2.3. Classification.
2.3.1. Phenetic classification. 2.3.2. Phylogenetic
classification. 2.3.4. Polyphasic classification.
2.3.5. Official classification. 3. Species and genus
definition. 3.1. Infraspecific and
suprageneric classification - pathovars. 4. Implication of
horizontal gene transfer for bacterial taxonomy. 5. Summary |
