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Plasmodiophora
''Plasmodiophora'' is a genus in class Phytomyxea The Phytomyxea are a class (biology), class of parasites that are cosmopolitan, obligate biotrophic protist parasites of plants, diatoms, oomycetes and brown algae. They are divided into the orders Plasmodiophorida (International Code of Zoolog .... It includes the species ''Plasmodiophora brassicae'', which causes the disease cabbage clubroot. References External links Tree of LifePlasmodiophorida Endomyxa Rhizaria genera Parasitic rhizaria Parasites of plants Crucifer diseases {{Cercozoa-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cabbage Clubroot
Clubroot is a common disease of cabbages, broccoli, cauliflower, Brussels sprouts, radishes, turnips, stocks, wallflowers and other plants of the family Brassicaceae (Cruciferae). It is caused by ''Plasmodiophora brassicae'', which was once considered a slime mold but is now put in the group Phytomyxea. It is the first phytomyxean for which the genome has been sequenced. It has as many as thirteen races. Gall formation or distortion takes place on latent roots and gives the shape of a club or spindle. In the cabbage such attacks on the roots cause undeveloped heads or a failure to head at all, followed often by decline in vigor or by death. It is an important disease, affecting an estimated 10% of the total cultured area worldwide. Historical reports of clubroot date back to the 13th century in Europe. In the late 19th century, a severe epidemic of clubroot destroyed large proportions of the cabbage crop in St. Petersburg. The Russian scientist Mikhail Woronin eventually identif ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Plasmodiophora Brassicae
''Plasmodiophora brassicae'' is a soilborne organism that is best known for its high economic impact on ''Brassica'' oil and vegetable crops. It infects 30 different Brassicaceae, cruciferous plants, which consists of up to 16 crop species, 9 ornamentals, and 5 weeds. The fungus on those plants causes a disease referred to as clubroot. Taxonomy ''Plasmodiophora brassicae'' was once referred to as a slime mold but was then transferred to the Phytomyxea group. Description ''Plasmodiophora brassicae'' exhibits two main forms within its life cycle. It is either a spore that is ready to infect roots or it becomes a persistent spore in the soil. That, or the fungus can become a somewhat mobile zoospore, which is a spindle shaped biflagellate cell. Life cycle ''Plasmodiophora brassicae'' life cycle consists of two main phases. Phase one is a Sporangium, sporangial stage which will lead to a short-lived zoospore. Stage two leads to a sporogenic phase which creates persistent rest ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Plasmodiophora Diplantherae
''Plasmodiophora'' is a genus in class Phytomyxea The Phytomyxea are a class (biology), class of parasites that are cosmopolitan, obligate biotrophic protist parasites of plants, diatoms, oomycetes and brown algae. They are divided into the orders Plasmodiophorida (International Code of Zoolog .... It includes the species ''Plasmodiophora brassicae'', which causes the disease cabbage clubroot. References External links Tree of LifePlasmodiophorida Endomyxa Rhizaria genera Parasitic rhizaria Parasites of plants Crucifer diseases {{Cercozoa-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Plasmodiophora Fici-repentis
''Plasmodiophora'' is a genus in class Phytomyxea. It includes the species ''Plasmodiophora brassicae'', which causes the disease cabbage clubroot Clubroot is a common disease of cabbages, broccoli, cauliflower, Brussels sprouts, radishes, turnips, stocks, wallflowers and other plants of the family Brassicaceae (Cruciferae). It is caused by ''Plasmodiophora brassicae'', which was once cons .... References External links Tree of LifePlasmodiophorida Endomyxa Rhizaria genera Parasitic rhizaria Parasites of plants Crucifer diseases {{Cercozoa-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Plasmodiophora Bicaudata
''Plasmodiophora bicaudata'' is a marine pathogen, an obligate parasite of seagrass of the genus ''Zostera'' and the causal agent of wasting disease in the genus. These marine plants grow in fine sediment in shallow seas and the pathogen seems to have a worldwide distribution. Biology The life cycle of ''Plasmodiophora bicaudata'' is complex. It includes resting spores which can lie dormant, awaiting suitable conditions to infect a new plant. Its other forms include two types of plasmodia, the feeding stage that derive their energy from the host cells, and two types of zoospores. The motile zoospores are the only form that can move outside the host cells. They have whiplash flagella and can swim to reach new seagrass plants and can also crawl on the surface of the leaves in an amoeboid way by extending pseudopodia forward. This parasite causes galls to form in the internodes of the rhizomes of its host seagrasses, species of the genus ''Zostera''. The condition is known as was ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phytomyxea
The Phytomyxea are a class (biology), class of parasites that are cosmopolitan, obligate biotrophic protist parasites of plants, diatoms, oomycetes and brown algae. They are divided into the orders Plasmodiophorida (International Code of Zoological Nomenclature, ICZN, or Plasmodiophoromycota, ICBN) and Phagomyxida. Plasmodiophore, Plasmodiophorids are best known as pathogens or vectors for viruses of arable crops (e.g. club root in Brassicaceae, powdery scab in potatoes, and Beet necrotic yellow vein virus, rhizomania in beets, especially Beta vulgaris saccarifera, sugar beets and some spinaches). Life cycle They typically develop within plant cells, causing the infected tissue to grow into a gall or scab. Important diseases caused by phytomyxeans include club root in cabbage and its relatives, and powdery scab in potatoes. These are caused by species of ''Plasmodiophora'' and ''Spongospora'', respectively.Agrios, George N. (2005). ''Plant Pathology''. 5th ed. Academic Presslin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rhizaria Genera
The Rhizaria are a diverse and species-rich clade of mostly unicellular eukaryotes. Except for the Chlorarachniophytes and three species in the genus ''Paulinella'' in the phylum Cercozoa, they are all non-photosynthetic, but many Foraminifera and Radiolaria have a symbiotic relationship with unicellular algae. A multicellular form, ''Guttulinopsis vulgaris'', a cellular slime mold, has been described. This group was used by Cavalier-Smith in 2002, although the term "Rhizaria" had been long used for clades within the currently recognized taxon. Being described mainly from rDNA sequences, they vary considerably in form, having no clear morphological distinctive characters (synapomorphies), but for the most part they are amoeboids with filose, reticulose, or microtubule-supported pseudopods. In the absence of an apomorphy, the group is ill-defined, and its composition has been very fluid. Some Rhizaria possess mineral exoskeletons ( thecae or loricas), which are in different cla ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Endomyxa
Endomyxa is a group of eukaryotic organisms in the supergroup Rhizaria. They were initially a subphylum of Cercozoa and later a subphylum of Retaria, but several analyses have proven they are a phylogenetically separate lineage, and Endomyxa is currently regarded as its own phylum In biology, a phylum (; : phyla) is a level of classification, or taxonomic rank, that is below Kingdom (biology), kingdom and above Class (biology), class. Traditionally, in botany the term division (taxonomy), division has been used instead .... References External links Rhizaria phyla {{Rhizaria-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Parasitic Rhizaria
Parasitism is a close relationship between species, where one organism, the parasite, lives (at least some of the time) on or inside another organism, the host, causing it some harm, and is adapted structurally to this way of life. The entomologist E. O. Wilson characterised parasites' way of feeding as "predators that eat prey in units of less than one". Parasites include single-celled protozoans such as the agents of malaria, sleeping sickness, and amoebic dysentery; animals such as hookworms, lice, mosquitoes, and vampire bats; fungi such as honey fungus and the agents of ringworm; and plants such as mistletoe, dodder, and the broomrapes. There are six major parasitic strategies of exploitation of animal hosts, namely parasitic castration, directly transmitted parasitism (by contact), trophicallytransmitted parasitism (by being eaten), vector-transmitted parasitism, parasitoidism, and micropredation. One major axis of classification concerns invasiveness: an endoparasi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
