Aphanomyces: A genus of OOMYCETES in the family Saprolegniaceae. It causes root rot in plants and is also a pathogen of FISHES.Oomycetes: Eukaryotes in the group STRAMENOPILES, formerly considered FUNGI, whose exact taxonomic level is unsettled. Many consider Oomycetes (Oomycota) a phylum in the kingdom Stramenopila, or alternatively, as Pseudofungi in the phylum Heterokonta of the kingdom Chromista. They are morphologically similar to fungi but have no close phylogenetic relationship to them. Oomycetes are found in both fresh and salt water as well as in terrestrial environments. (Alexopoulos et al., Introductory Mycology, 4th ed, pp683-4). They produce flagellated, actively motile spores (zoospores) that are pathogenic to many crop plants and FISHES.Celosia: A plant genus of the family AMARANTHACEAE. Young leaves are used as vegetables in Asia. Members contain betacyanins, celogentins, betaxanthin, and celosian.Astacoidea: A superfamily of various freshwater CRUSTACEA, in the infraorder Astacidea, comprising the crayfish. Common genera include Astacus and Procambarus. Crayfish resemble lobsters, but are usually much smaller.Plant Root Cap: A cone-shaped structure in plants made up of a mass of meristematic cells that covers and protects the tip of a growing root. It is the putative site of gravity sensing in plant roots.DNA, Algal: Deoxyribonucleic acid that makes up the genetic material of algae.Methenamine: An anti-infective agent most commonly used in the treatment of urinary tract infections. Its anti-infective action derives from the slow release of formaldehyde by hydrolysis at acidic pH. (From Martindale, The Extra Pharmacopoeia, 30th ed, p173)Spores, Fungal: Reproductive bodies produced by fungi.Peas: A variable annual leguminous vine (Pisum sativum) that is cultivated for its rounded smooth or wrinkled edible protein-rich seeds, the seed of the pea, and the immature pods with their included seeds. (From Webster's New Collegiate Dictionary, 1973)Fish Diseases: Diseases of freshwater, marine, hatchery or aquarium fish. This term includes diseases of both teleosts (true fish) and elasmobranchs (sharks, rays and skates).Plant Diseases: Diseases of plants.Plant Roots: The usually underground portions of a plant that serve as support, store food, and through which water and mineral nutrients enter the plant. (From American Heritage Dictionary, 1982; Concise Dictionary of Biology, 1990)Fishes: A group of cold-blooded, aquatic vertebrates having gills, fins, a cartilaginous or bony endoskeleton, and elongated bodies covered with scales.CapZ Actin Capping Protein: An actin capping protein that binds to the barbed-ends of ACTIN filaments. It is a heterodimer consisting of an alpha and a beta subunit. It regulates actin assembly by stabilizing actin oligomers for elongation. In SKELETAL MUSCLE, CapZ is localized to the Z-disk.Gelsolin: A 90-kDa protein produced by macrophages that severs ACTIN filaments and forms a cap on the newly exposed filament end. Gelsolin is activated by CALCIUM ions and participates in the assembly and disassembly of actin, thereby increasing the motility of some CELLS.Actins: Filamentous proteins that are the main constituent of the thin filaments of muscle fibers. The filaments (known also as filamentous or F-actin) can be dissociated into their globular subunits; each subunit is composed of a single polypeptide 375 amino acids long. This is known as globular or G-actin. In conjunction with MYOSINS, actin is responsible for the contraction and relaxation of muscle.Destrin: A member of the actin depolymerizing factors. Its depolymerizing activity is independent of HYDROGEN-ION CONCENTRATION.Serratia liquefaciens: A species of gram-negative bacteria in the genus SERRATIA found in plants and the DIGESTIVE TRACT of rodents. It is the most prevalent Serratia species in the natural environment.Cadmium Radioisotopes: Unstable isotopes of cadmium that decay or disintegrate emitting radiation. Cd atoms with atomic weights 103-105, 107, 109, 115, and 117-119 are radioactive cadmium isotopes.France: A country in western Europe bordered by the Atlantic Ocean, the English Channel, the Mediterranean Sea, and the countries of Belgium, Germany, Italy, Spain, Switzerland, the principalities of Andorra and Monaco, and by the duchy of Luxembourg. Its capital is Paris.Phytoplasma: A genus of minute bacteria in the family ACHOLEPLASMATACEAE that inhabit phloem sieve elements of infected PLANTS and cause symptoms such as yellowing, phyllody, and witches' brooms. Organisms lack a CELL WALL and thus are similar to MYCOPLASMA in animals. They are transmitted by over 100 species of INSECTS especially leafhoppers, planthoppers, and PSYLLIDS.Plant Pathology: The study of infectious diseases associated with plants.Acholeplasmataceae: Gram-negative organisms including apparently free-living saphrophytes as well as mammalian and avian parasites, and possibly pathogens.Peracetic Acid: A liquid that functions as a strong oxidizing agent. It has an acrid odor and is used as a disinfectant.Disinfectants: Substances used on inanimate objects that destroy harmful microorganisms or inhibit their activity. Disinfectants are classed as complete, destroying SPORES as well as vegetative forms of microorganisms, or incomplete, destroying only vegetative forms of the organisms. They are distinguished from ANTISEPTICS, which are local anti-infective agents used on humans and other animals. (From Hawley's Condensed Chemical Dictionary, 11th ed)Sodium Hypochlorite: It is used as an oxidizing and bleaching agent and as a disinfectant. (From Grant & Hackh's Chemical Dictionary, 5th ed)Oxolinic Acid: Synthetic antimicrobial related to NALIDIXIC ACID and used in URINARY TRACT INFECTIONS.Saprolegnia: A genus of OOMYCETES in the family Saprolegniaceae. It is a parasite and pathogen of freshwater FISHES.N-Acetylglucosaminyltransferases: Enzymes that catalyze the transfer of N-acetylglucosamine from a nucleoside diphosphate N-acetylglucosamine to an acceptor molecule which is frequently another carbohydrate. EC 2.4.1.-.Uridine Diphosphate N-Acetylglucosamine: Serves as the biological precursor of insect chitin, of muramic acid in bacterial cell walls, and of sialic acids in mammalian glycoproteins.Chitin Synthase: An enzyme that converts UDP glucosamine into chitin and UDP. EC Enzymes that catalyze the transfer of glucose from a nucleoside diphosphate glucose to an acceptor molecule which is frequently another carbohydrate. EC 2.4.1.-.Poecilia: A genus of livebearing cyprinodont fish comprising the guppy and molly. Some species are virtually all female and depend on sperm from other species to stimulate egg development. Poecilia is used in carcinogenicity studies as well as neurologic and physiologic research.Cyprinodontiformes: An order of fish with eight families and numerous species of both egg-laying and livebearing fish. Families include Cyprinodontidae (egg-laying KILLIFISHES;), FUNDULIDAEl; (topminnows), Goodeidae (Mexican livebearers), Jenynsiidae (jenynsiids), Poeciliidae (livebearers), Profundulidae (Middle American killifishes), Aplocheilidae, and Rivulidae (rivulines). In the family Poeciliidae, the guppy and molly belong to the genus POECILIA.Caves: Geological formations consisting of underground enclosures with access from the surface.Characidae: A family of fresh water fish in the order CHARACIFORMES, which includes the Tetras.MinnesotaCivilization: The distinctly human attributes and attainments of a particular society.History, Ancient: The period of history before 500 of the common era.Plants, Genetically Modified: PLANTS, or their progeny, whose GENOME has been altered by GENETIC ENGINEERING.Virgibacillus: A genus of GRAM-POSITIVE ENDOSPORE-FORMING RODS in the family BACILLACEAE. They have been isolated from salty environments, food, water, and clinical specimens.Color: The visually perceived property of objects created by absorption or reflection of specific wavelengths of light.Plant Leaves: Expanded structures, usually green, of vascular plants, characteristically consisting of a bladelike expansion attached to a stem, and functioning as the principal organ of photosynthesis and transpiration. (American Heritage Dictionary, 2d ed)Pythium: A genus of destructive root-parasitic OOMYCETES in the family Pythiaceae, order Peronosporales, commonly found in cultivated soils all over the world. Differentiation of zoospores takes place in a vesicle.Biological Science Disciplines: All of the divisions of the natural sciences dealing with the various aspects of the phenomena of life and vital processes. The concept includes anatomy and physiology, biochemistry and biophysics, and the biology of animals, plants, and microorganisms. It should be differentiated from BIOLOGY, one of its subdivisions, concerned specifically with the origin and life processes of living organisms.Hybridization, Genetic: The genetic process of crossbreeding between genetically dissimilar parents to produce a hybrid.Genetic Variation: Genotypic differences observed among individuals in a population.Molecular Sequence Data: Descriptions of specific amino acid, carbohydrate, or nucleotide sequences which have appeared in the published literature and/or are deposited in and maintained by databanks such as GENBANK, European Molecular Biology Laboratory (EMBL), National Biomedical Research Foundation (NBRF), or other sequence repositories.Evolution, Molecular: The process of cumulative change at the level of DNA; RNA; and PROTEINS, over successive generations.Phylogeny: The relationships of groups of organisms as reflected by their genetic makeup.Fatigue: The state of weariness following a period of exertion, mental or physical, characterized by a decreased capacity for work and reduced efficiency to respond to stimuli.Databases, Protein: Databases containing information about PROTEINS such as AMINO ACID SEQUENCE; PROTEIN CONFORMATION; and other properties.Sequence Analysis, Protein: A process that includes the determination of AMINO ACID SEQUENCE of a protein (or peptide, oligopeptide or peptide fragment) and the information analysis of the sequence.Systems Integration: The procedures involved in combining separately developed modules, components, or subsystems so that they work together as a complete system. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)Internet: A loose confederation of computer communication networks around the world. The networks that make up the Internet are connected through several backbone networks. The Internet grew out of the US Government ARPAnet project and was designed to facilitate information exchange.Proteome: The protein complement of an organism coded for by its genome.Proteins: Linear POLYPEPTIDES that are synthesized on RIBOSOMES and may be further modified, crosslinked, cleaved, or assembled into complex proteins with several subunits. The specific sequence of AMINO ACIDS determines the shape the polypeptide will take, during PROTEIN FOLDING, and the function of the protein.

Factors influencing the sporulation and cyst formation of Aphanomyces invadans, etiological agent of ulcerative mycosis in Atlantic menhaden, Brevoortia tyrannus. (1/22)

Oomycete infections caused by Aphanomyces invadans occur in freshwater and estuarine fishes around the world. Along the east coast of the USA, skin ulcers caused by A. invadans are prevalent in Atlantic menhaden, Brevoortia tyrannus. From laboratory observations low salinities appear crucial to transmission of the pathogen. To better understand aspects of transmission, we characterized sporulation and cyst formation of secondary zoospores of two isolates of A. invadans at different salinities and temperatures. Sporulation occurred only at low salinities. At room temperature (ca. 20-22 C), using "pond water" augmented with artificial sea salts, the endemic strain WIC and the Thailand strain PA7 of A. invadans produced free-swimming secondary zoospores at salinities of 0, 1 and 2 psu (practical salinity unit = per thousand), but not at 4 psu or higher. Secondary zoospores of another species, ATCC-62427 (Aphanomyces sp.), were observed at 1, 2, 4 and 8 psu but not at 0 and 12 psu. Secondary zoospores of all three isolates, especially WIC, were abundant and motile 1-2 d postsporulation. Sporulation was temperature dependent and occurred over a relatively narrow range. No sporulation occurred at 4, 30 or 35 C for either WIC or PA7. For both strains zoospore production within 1-3 d after the initiation of sporulation was more prolific at 25 C than at 20 and 15 C. At 15 C production of zoospores was sustained over 11 d for WIC and 5 d for PA7. At room temperature single WIC secondary zoospores remained motile 12-18 h. Salinities exceeding 4 psu or vigorous shaking caused immediate cyst formation of WIC secondary zoospores. Exposure to menhaden tissue, but not tissues of other fishes to secondary zoospores (WIC), caused rapid (2 h) cyst formation. Cysts were capable of excysting when transferred to 1 psu water within 2-3 h of cyst formation. Cysts that had remained encysted in 6.5 psu for 24 h did not excyst when transferred to 1 psu water. Salinity and temperature requirements for sporulation indicate that juvenile menhaden must acquire infections during rain or in low salinity oligohaline waters.  (+info)

Molecular assays for detecting Aphanomyces invadans in ulcerative mycotic fish lesions. (2/22)

The pathogenic oomycete Aphanomyces invadans is the primary etiological agent in ulcerative mycosis, an ulcerative skin disease caused by a fungus-like agent of wild and cultured fish. We developed sensitive PCR and fluorescent peptide nucleic acid in situ hybridization (FISH) assays to detect A. invadans. Laboratory-challenged killifish (Fundulus heteroclitus) were first tested to optimize and validate the assays. Skin ulcers of Atlantic menhaden (Brevoortia tyrannus) from populations found in the Pamlico and Neuse River estuaries in North Carolina were then surveyed. Results from both assays indicated that all of the lesioned menhaden (n = 50) collected in September 2004 were positive for A. invadans. Neither the FISH assay nor the PCR assay cross-reacted with other closely related oomycetes. These results provided strong evidence that A. invadans is the primary oomycete pathogen in ulcerative mycosis and demonstrated the utility of the assays. The FISH assay is the first molecular assay to provide unambiguous visual confirmation that hyphae in the ulcerated lesions were exclusively A. invadans.  (+info)

Phenolic constituents of Celosia cristata L. susceptible to spinach root rot pathogen Aphanomyces cochlioides. (3/22)

Cochliophilin A (5-hydroxy-6,7-methylenedioxyflavone, 1), known as a host-specific attractant towards the zoospores of Aphanomyces cochlioides, a cause of root rot and damping-off diseases of Chenopodiaceae, was found in the Amaranthaceae plant, Celosia cristata, that is susceptible to the pathogen. The content of 1 in Celosia seedlings was quantified as 1.4 microg/g fresh weight. A new isoflavone, cristatein (5-hydroxy-6-hydroxymethyl-7,2'-dimethoxyisoflavone, 2), and five known flavonoids were also identified.  (+info)

Detection of Aphanomyces astaci in North American crayfish by polymerase chain reaction. (4/22)

We present a PCR based method to detect Aphanomyces astaci in North American crayfish. Primers were designed to specifically amplify parts of the internal transcribed spacer (ITS) regions and the 5.8 rRNA gene of A. astaci. A single round and a semi-nested assay were tested for their sensitivity and specificity. Specificity of the PCR assays was tested against several closely related Aphanomyces species, other Oomycetes and some non-A. astaci DNA that might be found in or on crayfish. The single round assay was fully specific against all DNA tested. In the semi-nested assay, cross-reaction was seen when the equivalent of 40,000 or more genomic units of A. invadans or A. frigidophilus were entered into the PCR reaction. The lower detection limit of both assays lies around 1 genomic unit of A. astaci. Investigation of various parts of the exoskeleton of 3 North American crayfish species revealed that for O. limosus and P. leniusculus the telson and soft abdominal cuticle yielded a positive PCR reaction most frequently. For the third species, Procambarus clarkii, only 1 individual tested positive, so no conclusion as to preferred infestation site(s) could be drawn.  (+info)

AphanoDB: a genomic resource for Aphanomyces pathogens. (5/22)

BACKGROUND: The Oomycete genus Aphanomyces comprises devastating plant and animal pathogens. However, little is known about the molecular mechanisms underlying pathogenicity of Aphanomyces species. In this study, we report on the development of a public database called AphanoDB which is dedicated to Aphanomyces genomic data. As a first step, a large collection of Expressed Sequence Tags was obtained from the legume pathogen A. euteiches, which was then processed and collected into AphanoDB. DESCRIPTION: Two cDNA libraries of A. euteiches were created: one from mycelium growing on synthetic medium and one from mycelium grown in contact to root tissues of the model legume Medicago truncatula. From these libraries, 18,684 expressed sequence tags were obtained and assembled into 7,977 unigenes which were compared to public databases for annotation. Queries on AphanoDB allow the users to retrieve information for each unigene including similarity to known protein sequences, protein domains and Gene Ontology classification. Statistical analysis of EST frequency from the two different growth conditions was also added to the database. CONCLUSION: AphanoDB is a public database with a user-friendly web interface. The sequence report pages are the main web interface which provides all annotation details for each unigene. These interactive sequence report pages are easily available through text, BLAST, Gene Ontology and expression profile search utilities. AphanoDB is available from URL: http://www.polebio.scsv.ups-tlse.fr/aphano/.  (+info)

Transcriptome of Aphanomyces euteiches: new oomycete putative pathogenicity factors and metabolic pathways. (6/22)


Cell wall chitosaccharides are essential components and exposed patterns of the phytopathogenic oomycete Aphanomyces euteiches. (7/22)


No rosetta stone for a sense-antisense origin of aminoacyl tRNA synthetase classes. (8/22)


  • they are not all the same) in populations of Aphanomyces provides challenges for breeding programs, because specific resistances may not be active against all strains of the pathogen. (uwex.edu)
  • 1997), even though efforts have been made to breed for resistance to a wide variety of major pathogens of alfalfa such as Verticillium , Phytophthora , and Aphanomyces . (uwex.edu)
  • Roots and hypocotyls develop light to dark brown lesions, but unlike other root-rot pathogens which cause seedling collapse, hypocotyls infected with Aphanomyces tend to remain rigid, resulting in stunted but upright seedlings (Grau 1990). (uwex.edu)
  • Aphanomyces is an economically important genus of Oomycete pathogens that affect a wide range of hosts including crops such as alfalfa, bean, lentil, pea and sugarbeet. (usda.gov)
  • This proceeding summarizes scientific contributions from a recently held workshop on the genus Aphanomyces that emphasized the importance of these pathogens on legumes and sugarbeet. (usda.gov)
  • Aphanomyces survives as oospores (sexual spores) in the soil or in infected plant tissues. (uwex.edu)
  • Soils infested with Aphanomyces inoculum can be detected by planting bait plants into pots containing the field soil of interest and maintaining flooded conditions for 5 days. (uwex.edu)
  • Apron) are not active against Aphanomyces and therefore, avoiding poorly drained soils and using resistant varieties are the main methods useful for control. (uwex.edu)
  • Phylogenetic relationships among plant and animal parasites, and saprobionts in Aphanomyces (Oomycetes). (csic.es)
  • I think this point was made in the entry for _Phytophthora_, so I'm a little surprised by the repeated references to _Aphanomyces_ as a fungus. (blogspot.com)
  • The disease that manifests in plants infected with these water moulds is sometimes known simply as Aphanomyces root rot or common root rot. (wikipedia.org)
  • Our work provides the first evidence for the potential of OGs in the defense induction in pea against Aphanomyces root rot. (mdpi.com)
  • Effect of seed dressing fungicide and inoculum density on Aphanomyces root rot of field pea in Alberta. (gc.ca)
  • Recently, root rot caused by Aphanomyces euteiches was reported to be a concern where above-normal spring rainfall occurred. (gc.ca)
  • Experiments were conducted to determine effects of seed treatment and inoculum density on Aphanomyces root rot of field pea under greenhouse and field conditions. (gc.ca)
  • However the sterile growth-chamber experiments could be used to study the effect of S. meliloti inoculation on the development of Aphanomyces root rot. (wsu.edu)
  • The soil bacterium Bacillus mycoides MW 27 has excellent potential for development as a biological control agent of Aphanomyces root rot of pea. (lincoln.ac.nz)
  • In this study, we performed a meta-analysis of Aphanomyces root rot resistance QTL in the four main sources of resistance in pea and compared their genomic localization with genes/QTL controlling morphological or phenological traits and with putative candidate genes. (beds.ac.uk)
  • Aphanomyces causes two notifyable diseases: crayfish plague (J. Invertebr. (uis.no)
  • Highly resistant to all major alfalfa diseases, it's resistant to aphanomyces race 2 and has early season resistance to wet soil diseases. (beefmagazine.com)
  • It was the first fish diseases laboratory in Europe accredited for quality standards ISO 9001 and 17025 (EN 45001). (wur.nl)
  • Interestingly, tilapia are resistant to Aphanomyces infections. (vims.edu)
  • Apron) are not active against Aphanomyces and therefore, avoiding poorly drained soils and using resistant varieties are the main methods useful for control. (uwex.edu)
  • A pea-Aphanomyces collection of 175 pea lines, enriched in germplasm derived from previously studied resistant sources, was evaluated for resistance to A. euteiches in field infested nurseries in nine environments and with two strains in climatic chambers. (beds.ac.uk)
  • Antibodies cross-reacted with non-pathogenic Aphanomyces spp. (bl.uk)
  • Soils infested with Aphanomyces inoculum can be detected by planting bait plants into pots containing the field soil of interest and maintaining flooded conditions for 5 days. (uwex.edu)
  • Isolation of Aphanomyces sp(p). associated with skin lesions and morta" by AA Shaheen, E Elsayed et al. (wm.edu)
  • A formulation of the bacterium could be marketed on both its ability to increase yields under Aphanomyces disease pressure, and to limit oospore development, thereby limiting disease in continuous cropping situations. (lincoln.ac.nz)
  • Aphanomyces water moulds are "one of the most important yield-limiting factors in production of legumes and sugarbeet. (wikipedia.org)
  • 2001). A fatal oomycotic disease of the fresh water fish Aplocheilus panchax in India caused by Aphanomyces laevis. (wikipedia.org)
  • Taking a break from peas or lentils for six years is a tall order for fields where aphanomyces has been a problem. (realagriculture.com)