''Pseudomonas savastanoi'' is a
gram-negative plant pathogen
Plant pathology (also phytopathology) is the scientific study of diseases in plants caused by pathogens (infectious organisms) and environmental conditions (physiological factors). Organisms that cause infectious disease include fungi, oomyc ...
ic
bacterium that infects a variety of
plants. It was once considered a
pathovar of ''
Pseudomonas syringae,'' but following DNA-relatedness studies, it was instated as a new species.
It is named after Savastano, a worker who proved between 1887 and 1898 that olive knot are caused by bacteria.
[George M. Garrity: '']Bergey's Manual of Systematic Bacteriology
''Bergey's Manual of Systematic Bacteriology'' is the main resource for determining the identity of prokaryotic organisms, emphasizing bacterial species, using every characterizing aspect.
The manual was published subsequent to the ''Bergey's Manu ...
''. 2. Auflage. Springer, New York, 2005, Volume 2: ''The Proteobacteria, Part B: The Gammaproteobacteria''
The pathovar of greatest economical significance is ''Pseudomonas savastanoi'' pv. ''savastanoi'', which causes the disease
olive
The olive, botanical name ''Olea europaea'', meaning 'European olive' in Latin, is a species of small tree or shrub in the family Oleaceae, found traditionally in the Mediterranean Basin. When in shrub form, it is known as ''Olea europaea'' ...
knot.
Symptoms include formation of
galls on infected trees; tumour formation is induced by
indoleacetic acid biosynthesis by the bacteria, in a similar manner to the well-studied crown gall pathogen, ''
Agrobacterium tumefaciens
''Agrobacterium radiobacter'' (more commonly known as ''Agrobacterium tumefaciens'') is the causal agent of crown gall disease (the formation of tumours) in over 140 species of eudicots. It is a rod-shaped, Gram-negative soil bacterium. Sympto ...
''.
[Hosni T, et al. 2011. Sharing of quorum-sensing signals and role of interspecies communities in a bacterial plant disease. ISME J. .]
History
One of the first scientists to carry out scientific and modern research on the disease of
olive trees caused by ''Pseudomonas savastanoi'' ( it, la rogna dell'ulivo) was
Giuseppe Maria Giovene (1753-1837), who explained his conclusions in his publication ''Sulla rogna degli ulivi'' (1789).
Pathovars
* ''Pseudomonas savastanoi'' causes
ash canker.
[Smith, Dunez, Lelliot, Phillips and Archer (1988) European Handbook of Plant Disease. Blackwell Scientific Publications.]
* ''Pseudomonas savastanoi'' attacks
oleander.
* ''Pseudomonas savastanoi'' causes
olive
The olive, botanical name ''Olea europaea'', meaning 'European olive' in Latin, is a species of small tree or shrub in the family Oleaceae, found traditionally in the Mediterranean Basin. When in shrub form, it is known as ''Olea europaea'' ...
knot.
* ''Pseudomonas savastanoi'' attacks ''
Phaseolus
''Phaseolus'' (bean, wild bean) is a genus of herbaceous to woody annual and perennial vines in the family Fabaceae containing about 70 plant species, all native to the Americas, primarily Mesoamerica.
It is one of the most economically importan ...
'' (bean) plants
[B. P Borowicz, A Maćkowiak, H Pospieszny (2002) Improved identification of ''Pseudomonas savastanoi'' pv. ''phaseolicola'' at the molecular level. EPPO Bulletin 32 (3), 467–469.]
Quorum sensing
''P. s.'' pv. ''s.'' has an unusual
quorum sensing dynamic: It shares quorum with an entirely different
order
Order, ORDER or Orders may refer to:
* Categorization, the process in which ideas and objects are recognized, differentiated, and understood
* Heterarchy, a system of organization wherein the elements have the potential to be ranked a number of d ...
, the Enterobacterales.
Hosni et al., 2011 and Caballo-Ponce et al., 2018 find ''P. s.'' pv. ''s.'' produces very similar
''N''-Acyl homoserine lactones (AHLs) to the Erwiniaceae ''
Erwinia'' ''
toletana'' and ''
Pantoea agglomerans''.
Hosni find an avirulent mutant – defective for AHL production – is restored to virulence by the presence of ''E. toletana'' and ''P. agglomerans''.
These results demonstrate disease enhancing cooperation but also reveal a possible way that undiscovered cheating may be occurring.
References
External links
Type strain of ''Pseudomonas savastanoi'' at Bac''Dive'' - the Bacterial Diversity Metadatabase
Pseudomonadales
Bacterial plant pathogens and diseases
Fruit tree diseases
Pulse crop diseases
Bacteria described in 1982
{{Pseudomonadales-stub