Search results for "Pythium"

A new species of Pythium with inflated sporangia and coiled antheridia, isolated from India

2008

Pythium kashmirense sp. nov. was isolated from soil samples taken on the Himalayas at the height of 5300 feet in the Shivalik Hill Range of the northern Indian state of Jammu and Kashmir. The oomycete has filamentous-inflated type sporangia and its antheridial filaments form loose loops around the female gametangia, and coil around the oogonial stalks. The new species is closely related to Pythium plurisporium, Pythium periilum, Pythium inflatum, and Pythium folliculosum. All of these oomycetes have filamentous-inflated type sporangia. However, P. kashmirense has its own distinguishing characteristics which can easily differentiate it among these related species. The sequences of the intern…

A new species of Pythium with filamentous sporangia having pectinolytic activities, isolated in the Burgundy region of France.

2001

A new species, Pythium pectinolyticum (F-83.1), isolated from soil samples taken in the Burgundy region is being described here. This species is characterised by its filamentous non-inflated type of sporangia, smooth-walled mostly catenulate oogonia and very rare antheridia. This fungus is a very slow-growing organism on most of the solid media, but it grows well in liquid media and also on those containing pectin as the sole source of carbon. Morphological features are described here together with the sequences of the internal transcribed spacer 1 region of the nuclear ribosomal DNA of the fungus, its comparison with related species, and its pectinolytic behaviour.

Purification, crystallization and preliminary X-ray studies of sylvaticin, an elicitin-like protein from Pythium sylvaticum.

2003

Sylvaticin belongs to the elicitin family. These 10 kDa oomycetous proteins induce a hypersensitive response in plants, including necrosis and cell death, but subsequently leading to a non-specific systemic acquired resistance (SAR) against other pathogens. Sylvaticin has been crystallized using PEG 2000 MME as a precipitant agent in the presence of nickel chloride. The crystals belong to space group C2, with unit-cell parameters a = 99.29, b = 25.67, c = 67.45 A, beta = 99.66 degrees. Diffraction data were recorded to 2.1 A resolution at a synchrotron-radiation source.

Suppressiveness of 18 composts against 7 pathosystems : variability in pathogen response

2006

International audience; Compost is often reported as a substrate that is able to suppress soilborne plant pathogens, but suppression varies according to the type of compost and pathosystem. Reports often deal with a single pathogen while in reality crops are attacked by multiple plant pathogens. The goal of the present study was to evaluate the disease suppression ability of a wide range of composts for a range of plant pathogens. This study was conducted by a consortium of researchers from several European countries. Composts originated from different countries and source materials including green and yard waste, straw, bark, biowaste and municipal sewage. Suppressiveness of compost-amende…

Isolation frequency and efficiency of mycoparasitic Pythium species in the West Mediterranean region of Turkey

2021

Abstract A total of 132 mycoparasitic Pythium isolates were obtained from the soil samples taken from fruit orchards, vegetable fields, carnation greenhouses, sugarbeet fields and cereal fields in the West Mediterranean region of Turkey. The Oomycetes were isolated by using; surface soil dilution plate, sclerotia bait and precolonised plate methods. Isolates were identified as P. acanthophoron, P. amasculinum, P. lycopersicum, P. oligandrum, P. periplocum and P. paroecandrum, according to their morphological and molecular characteristics. The most commonly isolated mycoparasitic species were P. amasculinum and P. lycopersicum. The majority of the mycoparasites came from soil samples taken f…

CTAB‐PLGA Curcumin Nanoparticles: Preparation, Biophysical Characterization and Their Enhanced Antifungal Activity against Phytopathogenic Fungus Pyt…

2020

Diversity of root-associated fluorescent pseudomonads as affected by ferritin overexpression in tobacco

2007

A transgenic tobacco overexpressing ferritin (P6) was recently shown to accumulate more iron than the wild type (WT), leading to a reduced availability of iron in the rhizosphere and shifts in the pseudomonad community. The impact of the transgenic line on the community of fluorescent pseudomonads was assessed. The diversity of 635 isolates from rhizosphere soils, rhizoplane + root tissues, and root tissues of WT and P6, and that of 98 isolates from uncultivated soil was characterized. Their ability to grow under iron stress conditions was assessed by identifying their minimal inhibitory concentrations of 8-hydroxyquinoline for each isolate, pyoverdine diversity by isoelectrofocusing and ge…

Pythium periplocum, an aggressive mycoparasite of Botrytis cinerea causing the gray mould disease of grape-vine.

1999

Pythium periplocum Dreschler has been found to be an aggressive mycoparasite of Botrytis cinerea, the causal agent of the gray mould disease of the grape-vine. When grown together, the former enters the latter's mycelium, branches freely within, coagulates its cytoplasm and finally tears its hyphae apart, bringing about widespread destruction of the grape-vine pathogen. Extensive coiling around the host, as reported in the case of other mycoparasites belonging to the genus Pythium, has not been observed here. The infected mycelium of B. cinerea fails to infect the grape-vine and does not induce the characteristic gray mould symptoms. Since P. periplocum is not a grape-vine parasite, it coul…

A new species of Pythium with ornamented oogonia: morphology, taxonomy, internal transcribed spacer region of its ribosomal RNA, and its comparison w…

2006

Pythium spiculum sp. nov. was isolated from soil samples taken in a vineyard in the Burgundian region of France and from different locations in Spain and Portugal. The oomycete has spiny oogonia and does not sporulate readily. It resembles Pythium mamillatum Meurs, but has its own distinguishing characteristics. It also exhibits sickle-shaped as well as spherical appressoria which at times are associated with sex organs like those found in Pythium abappressorium Paulitz and Pythium contiguanum Paul. Sequencing of the internal transcribed spacer region of its nuclear ribosomal DNA and a close look at its morphological characters have now enabled us to describe it as a new species. The intern…

A new species ofPythiumisolated from burgundian vineyards and its antagonism towardsBotrytis cinerea, the causative agent of the grey mould disease

2004

During the course of an investigation on the pythiaceous fungi occurring in burgundian vineyards, three isolates of Pythium were found, all of which were characterised by spherical to lemoniform, proliferating sporangia. Only one out of these three isolates produced sexual characters (S-12) after prolonged incubation, but their asexual structures, temperature growth relationship and molecular characteristics were identical. Saprolegnia-type internal proliferation of the sporangia, and Phytophthora-type lemoniform, papillate sporangia were characteristic of all the three isolates. The type specimen is S-12 which is a medium slow growing saprophyte. The sequence of its ITS region of the rDNA …