Pythium porphyrae
| Pythium porphyrae | |
|---|---|
Scientific classification 
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| Domain: | Eukaryota |
| Clade: | Diaphoretickes |
| Clade: | SAR |
| Clade: | Stramenopiles |
| Phylum: | Oomycota |
| Order: | Peronosporales |
| Family: | Pythiaceae |
| Genus: | Pythium |
| Species: | P. porphyrae
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| Binomial name | |
| Pythium porphyrae | |
| Synonyms[2][3][4] | |
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Pythium porphyrae, is a parasitic species of oomycete in the family Pythiaceae.[5] It is the cause of red rot disease or red wasting disease, also called akagusare (赤ぐされ) in Japanese.[1][6] The specific epithet porphyrae (πορφυρα) stems from the genus of one of its common hosts, Porphyra, and the purple-red color of the lesions on the thallus of the host.[7] However, many of its hosts have been moved from the genus Porphyra to Pyropia.
Economic impact
[edit]Pythium porphyrae can destroy an entire crop of nori within three weeks.[8][9][6] It prefers low salinity and warm water (24-28 °C).[10][11][12][6] It will only grow in the 15-35 °C range.[13] Mild winters correlate with higher infestations and lower crop yields,[14] possibly due to decreased temperatures inducing the development of sex organs in the oomycete.[1] Losses can be combated by destroying diseased fronds and exposing thalli to the air for 3–4 hours daily.[6] The oospores can be spread in contaminated organic matter and the sporangia can spread through the water.[15]
Description
[edit]Pythium porphyrae has a mycelial thallus that is eucarpic, meaning only part of the thallus turns into sporangia.[15] It is primarily a facultative parasite of algae, but can also be saprobic.[15]
Its hyphae can grow up to 4.5 μm wide,[13][15] and are not septate.[1] On algae, the hyphae will extend through the cell wall.[1] It does not have haustoria not chlamydospores.[15] The appressoria are club-shaped.[15] It has sporangia that are unbranched, filamentous,[1][3] and non-inflated,[3] typically forming 6-17 zoospores per vesicle.[1][13][15] Encysted zoospores are 8-12 μm in diameter.[15] Hyphal swellings are intercalary and globose, from 12-28 μm in diameter.[15] Oogonia average 17 μm in diameter and are also intercalary and globose, but rarely are terminal.[13][15] In each oogonium are 1-2 diclinous antheridia[3][15][1] coming out far away from the oogonial stalk.[13] The antheridia's cells are clavate (club shaped) or globose.[1][13][15] The antheridia will be apical to the oogonial wall.[15] Sometimes there will be two antheridial cells on one stalk.[13] The yellowish oospores average 15 μm in diameter, have thick (~2 μm) walls, and are plerotic (fill the whole oogonium).[13][15] Conidia are spherical at 8.8-30.8 μm diameter, but rarely produced.[1]
Pythium porphyrae shares many physical traits with P. marinum and P. monospermum,[13] and appears to be most closely related to P. adhaerens.[2][3] However it has up to four diclinous antheridia and sometimes two antheridial cells per stalk; P. monospermum has 1-4 either diclinous or monoclinous antheridia and P. marinum has only a single diclinous antheridium.[13] P. monospermum and P. marinum also have oogonia terminally on short branches, yet in P. porphyrae they tent to be intercalary.[13]
In a laboratory it will grow 5 mm per day[3] on seawater-cornmeal agar with low aerial mycelium[15] and colorless colonies,[1] but will not grow at all on potato-carrot agar.[13]
Ecology
[edit]Pythium porphyrae has been found in Japan,[1] Netherlands, New Zealand,[2] and Korea, but this range is likely underreported.[15] It has a parasitic relationship with the following hosts. Though some species of Pyropia and Porphyra are susceptible to infection in their gametophytic phase, they are resistant in their Conchocelis (sporophytic) phase.[2]
- Bangia atropurpurea[15]
- Callophyllis adhaerens[15]
- Chondrus crispus[2][3]
- Gelidium elegans[15]
- Gloiosiphonia capillaris[15]
- Gracilaria spp.[15]
- Grateloupia turuturu[15]
- Griffithsia subcylindrica[15]
- Lomentaria hakodatensis[15]
- Mastocarpus papillatus[16]
- Polyopes affinis (Carpopeltis affinis)[15]
- Polysiphonia morrowii[15]
- Pterocladiella capillacea[15]
- Pyropia cinnamomea[2]
- Pyropia plicata[2]
- Pyropia suborbiculata[2]
- Pyropia tenera[2][10][15][1]
- Pyropia virididentata[2]
- Pyropia yezoensis[13][3][15][1]
- Rhodymenia intricata[15]
- Stylonema alsidii[15]
- Wrangelia tanegana[15]
Taxonomy
[edit]A 2005 study concerning a case of Pythiosis from a related species (P. insidiosum) indicated that P. porphyrae is related to P. dissotocum, P. myriotylum, P. volutum, and P. vanterpoolii.[17]
In 2004, molecular analysis of Pythium determined that P. porphyrae is in "Clade A" along with P. adhaerens, P. deliense, P. aphanidermatum, and P. monospermum[3] Clade A has two clusters, and P. porphyrae shares one with the species also originating on algae, P. adhaerens.[3]
A 2017 study of Pythium species in Clade A showed the following phylogenetic tree.[2] It further demonstrated that P. porphyrae and P. chondricola are the same species.[2][3] P. adhaerens may also be conspecific based solely on genetic comparison, but showed a number of physical differences that show it may be a separate but very closely related species.[2]
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See also
[edit]References
[edit]- ^ a b c d e f g h i j k l m n Takahashi, Minoru; Ichitani, Takio; Sasaki, Minoru (1977). "ノリ赤腐病を起因するPythium porphyrae" [Pythium porphyrae sp. nov. causing red rot of marine algae Porphyra spp.]. Transactions of the Mycological Society of Japan. 18 (3): 279–285.
- ^ a b c d e f g h i j k l m Diehl, Nora; Kim, Gwang Hoon; Zuccarello, Giuseppe C. (March 2017). "A pathogen of New Zealand Pyropia plicata (Bangiales, Rhodophyta), Pythium porphyrae (Oomycota)". Algae. 32 (1): 29–39. doi:10.4490/algae.2017.32.2.25. OCLC 7067179428.
- ^ a b c d e f g h i j k LéVesque, C.André; De Cock, Arthur W.A.M. (December 2004). "Molecular phylogeny and taxonomy of the genus Pythium". Mycological Research. 108 (12): 1363–1383. doi:10.1017/S0953756204001431. ISSN 0953-7562. OCLC 358362888. PMID 15757173.
- ^ "Pythium porphyrae". MycoBank. Utrecht, Netherlands. 2016. Retrieved 4 October 2017.
- ^ "Pythium porphyrae". NCBI Taxonomy. Bethesda, MD: National Center for Biotechnology Information. Retrieved 2 October 2017.
Lineage( full ) cellular organisms; Eukaryota; Stramenopiles; Oomycetes; Pythiales; Pythiaceae; Pythium
- ^ a b c d Andrews, John H. (May 1976). "The Pathology of Marine Algae. Diseases caused by phycomycetes: Chytridiomycetes; Hyphochytridiomycetes; Oomycetes". Biological Reviews. 51 (2): 211–252. doi:10.1111/j.1469-185X.1976.tb01125.x. ISSN 1464-7931. S2CID 85175801.
- ^ Griffith, Chuck (2005). "Dictionary of Botanical Epithets". Dictionary of Botanical Epithets. Retrieved 3 October 2017.
purple-red porphyra porphyr noun/f πορφυρα the purple-fish or the dye that was made from it
- ^ Arasaki, S. (1956). "The diseases of asakusanori and their control" [The diseases of asakusanori and their control]. 病蟲害雜誌 (Plant Protection) (in Japanese). 10: 243–6. OCLC 41036343.
- ^ ARASAKI, S. (1962). Studies on the artificial culture of Porphyra tenera Kjellm. 111. On the red wasting disease of Porphyra, especially on the physiology of the causal fungus Pythium sp.nov. [In Japanese, English summary.] Journal of the Agricultural Laboratory, Abiko, Japan. Central Research Institute of Electric Power Industry 3, 87-93
- ^ a b Arasaki, Satoshi (1947). "アサクサノリめ腐敗病に關する研究" [Studies on the Wasting Disease of the Cultured Lavers (Porphyra tenera)]. Nippon Suisan Gakkaishi (Bulletin of the Japanese Society of Scientific Fisheries) (in Japanese). 13 (3): 74–90. doi:10.2331/suisan.13.74. ISSN 0021-5392.
- ^ SUTO, S., SAITO, Y., AKIYAMA, K. & UMEBAYASHI, 0. (1972). Text Book of Diseases and their Symptoms in Porphyra. [In Japanese.] Contribution E, Number I 8 of Tokai Regional Fisheries Research Laboratory, Japan. 37 pp.
- ^ SAKURAI, Y., AKIYAMA, K. & SATO, S. (1974). On the formation and the discharge of zoospores of Pythium porphyrae in experimental conditions. [In Japanese, English summary.] Bulletin of the Tohoku Regional Fisheries Research Laboratory (33), I 19-27.
- ^ a b c d e f g h i j k l m van der Plaats-Niterink, J. (22 December 1981). "IX. Descriptions of the recognized species". Monograph of the genus Pythium. Studies in Mycology. Vol. 21. Baarn, Netherlands: Centraalbureau voor Schimmelcultures. OCLC 474297038. Archived from the original on 1 December 2017. Retrieved 6 October 2017.
- ^ Suto, S (1953). "Seaweed production and phycological research in Japan". Proceedings of the 1st International Seaweed Symposium, Edinburgh, 14–17 July 1952: 96–99. OCLC 22404162.
- ^ a b c d e f g h i j k l m n o p q r s t u v w x y z aa ab ac ad ae af Spencer, M. A. (2004). "Pythium porphyrae. (Descriptions of Fungi and Bacteria)". IMI Descriptions of Fungi and Bacteria. 162 (Sheet 1617). Retrieved 10 October 2017.
A description is provided for Pythium porphyrae. Information is included on the disease caused by the organism, its transmission, geographical distribution, and hosts. DISEASES: Red-rot disease, red-wasting disease. HOSTS: Bangia atropurpurea, Callophyllis adhaerens, Polyopes affinis (syn
- ^ "Turkish Washcloth or Black Tar Spot". Slater Museum of Natural History. Slater Museum of Natural History. Marine Panel. Tacoma, WA: University of Puget Sound. 2017. Retrieved 6 October 2017.
- ^ Rivierre, Christine; Laprie, Caroline; Guiard-Marigny, Olivier; Bergeaud, Patrick; Berthelemy, Madeleine; Guillot, Jacques (March 2005). "Pythiosis in Africa". Emerging Infectious Diseases. 11 (3): 479–481. doi:10.3201/eid1103.040697. ISSN 1080-6059. OCLC 815385893. PMC 3298269. PMID 15757572. Retrieved 5 October 2017.
External links
[edit]
Data related to Pythium porphyrae at Wikispecies
