"''Pseudomonas helianthi''" is a

Gram-negative Gram-negative bacteria are bacteria that do not retain the crystal violet stain used in the Gram staining method of bacterial differentiation. They are characterized by their cell envelopes, which are composed of a thin peptidoglycan cell wa ...

plant Plants are predominantly Photosynthesis, photosynthetic eukaryotes of the Kingdom (biology), kingdom Plantae. Historically, the plant kingdom encompassed all living things that were not animals, and included algae and fungi; however, all curr ...

pathogenic

bacterium Bacteria (; singular: bacterium) are ubiquitous, mostly free-living organisms often consisting of one biological cell. They constitute a large domain of prokaryotic microorganisms. Typically a few micrometres in length, bacteria were a ...

that infects a variety of

s. It was once considered a

pathovar A pathovar is a bacterial strain or set of strains with the same or similar characteristics, that is differentiated at infrasubspecific level from other strains of the same species or subspecies on the basis of distinctive pathogenicity to one o ...

of ''

Pseudomonas syringae ''Pseudomonas syringae'' is a rod-shaped, Gram-negative bacterium with polar flagella. As a plant pathogen, it can infect a wide range of species, and exists as over 50 different pathovars, all of which are available to researchers from interna ...

,'' but following DNA-relatedness studies, it was recognized as a separate species and ''P. syringae'' pv. ''tagetis'' was incorporated into it, as well. Since no official name has yet been given, it is referred to by the epithet '' 'Pseudomonas helianthi' ''.

Pathovars

* "''Pseudomonas helianthi''" pv. ''helianthi'' attacks sunflowers (''

Helianthus annuus The common sunflower (''Helianthus annuus'') is a large annual forb of the genus ''Helianthus'' grown as a crop for its Sunflower seed, edible oily seeds. Apart from sunflower oil, cooking oil production, it is also used as livestock forage (as ...

''). * "''Pseudomonas helianthi''" pv. ''tagetis'' attacks marigolds (''

Tagetes erecta ''Tagetes erecta'', the Aztec marigold, Mexican marigold, big marigold, ''cempazúchitl'' or ''cempasúchil'', is a species of flowering plant in the genus ''Tagetes'' native to Mexico. Despite being native to the Americas, it is often called the ...

'').

References

Pseudomonadales Bacterial plant pathogens and diseases Ornamental plant pathogens and diseases Undescribed species {{Pseudomonadales-stub