Oomycetes


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Oomycetes

A class of fungi in the subdivision Mastigomycotina. They comprise a group of heterotropic, funguslike organisms that are classified with the zoosporic fungi (Mastigomycotina) but in reality are related to the heterokont algae. They are distinguished from other zoosporic fungi by the presence of biflagellate zoospores. Some taxa are nonzoosporic. Asexual reproduction involves the release of zoospores from sporangia; in some taxa the sporangium germinates with outgrowth of a germ tube. Sexual reproduction occurs when an oogonial cell is fertilized by contact with an antheridium, resulting in one or more oospores.

Oomycetes are cosmopolitan, occurring in fresh and salt water, in soil, and as terrestrial parasites of plants. Many species can be grown in pure culture on defined media. There are four orders: The Saprolegniales and Leptomitales are popularly known as water molds. Some species are destructive fish parasites. Many Lagenidiales are parasites of invertebrates and algae. The Peronosporales are primarily plant parasites attacking the root, stem, or leaf, and include some of the more destructive plant pathogens. See Eumycota, Fungi

McGraw-Hill Concise Encyclopedia of Bioscience. © 2002 by The McGraw-Hill Companies, Inc.

Oomycetes

[‚ō·ə·mī′sēd·ēz]
(mycology)
A class of the Phycomycetes comprising the biflagellate water molds and downy mildews.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.
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Chemical control which include synthetic fungicides such as metalaxyl spray are among the most widely used methods, however, they are ineffective to new strains of the oomycete produced as recombinants of fertilization (Axel et al., 2012).
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2016) and oomycetes pathogens such as Pythium aphanidermatum (Hendrix, Campbell 1973).
Kamoun S, Furzer O, Jones JD, Judelson HS, Ali GS, Dalio RJ, Roy SG, Schena L, Zambounis A, Panabieres F, Cahill D, Ruocco M, Figueiredo A, Chen XR, Hulvey J, Stam R, Lamour K, Gijzen M, Tyler BM, Grunwald NJ, Mukhtar MS, Tome DF, Tor M, Van Den Ackerveken G, McDowell J, Daayf F, Fry WE, LindqvistKreuze H, Meijer HJ, Petre B, Ristaino J, Yoshida K, Birch PR, Govers F (2015) The top 10 oomycete pathogens in molecular plant pathology.
Species identification in the genus Saprolegnia (Oomycetes): defining DNA-based molecular operational taxonomic units.
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It is used across the world for the control of various fungi, especially Oomycetes, Ascomycetes, Basidiomycetes and Fungi imperfecti.