''Polymyxa graminis'' is a species of
plasmodiophorid
The plasmodiophores (also known as plasmophorids or plasmodiophorids) are a group of obligate endoparasitic protists belonging to the subphylum Endomyxa in Cercozoa. Taxonomically, they are united under a single family Plasmodiophoridae, order Pl ...
cercozoa
Cercozoa (now synonymised with Filosa) is a phylum of diverse single-celled eukaryotes. They lack shared morphological characteristics at the microscopic level, and are instead united by phylogeny, molecular phylogenies of rRNA and actin or Ubiqu ...
ns. It is an obligate
parasite
Parasitism is a Symbiosis, close relationship between species, where one organism, the parasite, lives (at least some of the time) on or inside another organism, the Host (biology), host, causing it some harm, and is Adaptation, adapted str ...
of
plant
Plants are the eukaryotes that form the Kingdom (biology), kingdom Plantae; they are predominantly Photosynthesis, photosynthetic. This means that they obtain their energy from sunlight, using chloroplasts derived from endosymbiosis with c ...
root
In vascular plants, the roots are the plant organ, organs of a plant that are modified to provide anchorage for the plant and take in water and nutrients into the plant body, which allows plants to grow taller and faster. They are most often bel ...
s and, though itself non-pathogenic, is responsible for the
transmission
Transmission or transmit may refer to:
Science and technology
* Power transmission
** Electric power transmission
** Transmission (mechanical device), technology that allows controlled application of power
*** Automatic transmission
*** Manual tra ...
of several very important
plant virus
Plant viruses are viruses that have the potential to affect plants. Like all other viruses, plant viruses are obligate intracellular parasites that do not have the molecular machinery to replicate without a host. Plant viruses can be pathoge ...
es, including
barley yellow mosaic virus
Barley yellow mosaic virus is plant pathogenic virus that causes the yellow mosaic disease of barley. Its shape is categorized as being flexuous filamentous, with lengths of 275 and 550 nanometers. The virus has a limited host range, and barley ...
(BaYMV) and
soil-borne wheat mosaic virus (SBWMV).
References
Plasmodiophorid Home Page* Konstantin Kanyuka, Elaine Ward and Michael J. Adams. ''Polymyxa graminis and the cereal viruses it transmits: a research challenge''. Molecular Plant Pathology, Vol 4 page 393.
Endomyxa
Plant pathogens and diseases by vector
Rhizaria species
{{Cercozoa-stub